PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (1317918)

Clipboard (0)
None

Related Articles

1.  Immune Reconstitution Inflammatory Syndrome following Antiretroviral Therapy Initiation in Tuberculosis Patients: Findings from the SAPiT Trial 
Annals of internal medicine  2012;157(5):313-324.
Background
Concerns about immune reconstitution inflammatory syndrome (IRIS) remain a barrier to antiretroviral therapy (ART) initiation during anti-tuberculosis treatment in co-infected patients.
Objective
We assessed IRIS incidence, severity, and outcomes relative to timing of ART initiation in patients with HIV-related tuberculosis (HIV-TB).
Setting
An outpatient clinic in Durban, South Africa
Patients
642 HIV-TB co-infected patients
Design
In a secondary analysis of the SAPiT trial, IRIS was assessed in patients randomized to initiate ART either within four weeks of tuberculosis treatment initiation (early integrated-treatment arm), within four weeks of completion of the intensive phase of tuberculosis treatment (late integrated-treatment arm) or within four weeks after tuberculosis therapy completion (sequential-treatment arm). IRIS was defined as new onset or worsening symptoms, signs or radiographic manifestations temporally related to treatment initiation accompanied by a treatment response. IRIS severity, hospitalization and time to resolution were monitored.
Results
IRIS incidence was 19.5 (n=43), 7.5 (n=18) and 8.1 (n=19) per 100 person-years in the early integrated-, late integrated-, and sequential-treatment arms, respectively; P < 0.001, and 45.5, 9.7 and 19.7 per 100 person-years in patients with baseline CD4+ counts <50 cells/mm3, P = 0.004. IRIS incidence was higher in the early integrated- compared to the late integrated- (incidence rate ratio (IRR) = 2.6, 95%confidence interval (CI): 1.5 to 4.8; P < 0.001) or sequential-treatment arm (IRR=2.4, 95%CI: 1.4 to 4.4; P < 0.001). IRIS cases in the early integrated-treatment arm were more severe (34.9% vs. 18.9%, P = 0.18); had significantly higher hospitalization rates (18/43 vs. 5/37; P = 0.01), and longer time to resolution (70.5 vs. 29.0 days; P = 0.001) compared to IRIS cases in the other two arms.
Limitation
IRIS could not be assessed, due to LTFU, withdrawal or death within 6 months of scheduled ART initiation, in more patients from the sequential treatment arm (n=74) than in the late integrated treatment arm (n=50) and in the early integrated treatment arm (n=32). This study did not assess IRIS risk in non-ambulant patients and in patients with extra-pulmonary and smear negative pulmonary tuberculosis.
Conclusion
Initiation of ART early during tuberculosis treatment resulted in significantly higher IRIS rates, with longer time to resolution, and more severe cases of IRIS requiring hospitalization. These findings, particularly relevant to patients initiating ART with CD4+ counts < 50 cells/mm3, need to be considered together with the increased survival benefit of early ART initiation in this group. Clintrials.gov: NCT00398996
doi:10.7326/0003-4819-157-5-201209040-00004
PMCID: PMC3534856  PMID: 22944873
2.  The HIV Treatment Gap: Estimates of the Financial Resources Needed versus Available for Scale-Up of Antiretroviral Therapy in 97 Countries from 2015 to 2020 
PLoS Medicine  2015;12(11):e1001907.
Background
The World Health Organization (WHO) released revised guidelines in 2015 recommending that all people living with HIV, regardless of CD4 count, initiate antiretroviral therapy (ART) upon diagnosis. However, few studies have projected the global resources needed for rapid scale-up of ART. Under the Health Policy Project, we conducted modeling analyses for 97 countries to estimate eligibility for and numbers on ART from 2015 to 2020, along with the facility-level financial resources required. We compared the estimated financial requirements to estimated funding available.
Methods and Findings
Current coverage levels and future need for treatment were based on country-specific epidemiological and demographic data. Simulated annual numbers of individuals on treatment were derived from three scenarios: (1) continuation of countries’ current policies of eligibility for ART, (2) universal adoption of aspects of the WHO 2013 eligibility guidelines, and (3) expanded eligibility as per the WHO 2015 guidelines and meeting the Joint United Nations Programme on HIV/AIDS “90-90-90” ART targets. We modeled uncertainty in the annual resource requirements for antiretroviral drugs, laboratory tests, and facility-level personnel and overhead.
We estimate that 25.7 (95% CI 25.5, 26.0) million adults and 1.57 (95% CI 1.55, 1.60) million children could receive ART by 2020 if countries maintain current eligibility plans and increase coverage based on historical rates, which may be ambitious. If countries uniformly adopt aspects of the WHO 2013 guidelines, 26.5 (95% CI 26.0 27.0) million adults and 1.53 (95% CI 1.52, 1.55) million children could be on ART by 2020. Under the 90-90-90 scenario, 30.4 (95% CI 30.1, 30.7) million adults and 1.68 (95% CI 1.63, 1.73) million children could receive treatment by 2020. The facility-level financial resources needed for scaling up ART in these countries from 2015 to 2020 are estimated to be US$45.8 (95% CI 45.4, 46.2) billion under the current scenario, US$48.7 (95% CI 47.8, 49.6) billion under the WHO 2013 scenario, and US$52.5 (95% CI 51.4, 53.6) billion under the 90-90-90 scenario. After projecting recent external and domestic funding trends, the estimated 6-y financing gap ranges from US$19.8 billion to US$25.0 billion, depending on the costing scenario and the U.S. President’s Emergency Plan for AIDS Relief contribution level, with the gap for ART commodities alone ranging from US$14.0 to US$16.8 billion.
The study is limited by excluding above-facility and other costs essential to ART service delivery and by the availability and quality of country- and region-specific data.
Conclusions
The projected number of people receiving ART across three scenarios suggests that countries are unlikely to meet the 90-90-90 treatment target (81% of people living with HIV on ART by 2020) unless they adopt a test-and-offer approach and increase ART coverage. Our results suggest that future resource needs for ART scale-up are smaller than stated elsewhere but still significantly threaten the sustainability of the global HIV response without additional resource mobilization from domestic or innovative financing sources or efficiency gains. As the world moves towards adopting the WHO 2015 guidelines, advances in technology, including the introduction of lower-cost, highly effective antiretroviral regimens, whose value are assessed here, may prove to be “game changers” that allow more people to be on ART with the resources available.
Arin Dutta and colleagues project global ART-related funding, global ART-related need under established targets, and the gap between the two.
Editors' Summary
Background
AIDS has killed 39 million people since 1981, and over 36 million people (mostly living in resource-limited countries) are currently living with HIV, the virus that causes AIDS. HIV destroys immune system cells (including CD4 lymphocytes), leaving HIV-infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected individuals died within ten years of infection. Then, in 1996, effective antiretroviral therapy (ART) became available. For people living in affluent countries, HIV/AIDS became a chronic condition, but it remained fatal for people living in resource-limited countries. In 2003, the international community began to work towards universal access to ART. Now, more than a third of people living with HIV are receiving ART, and the global death rate from HIV/AIDS is falling. The “90-90-90” targets recently set by UNAIDS—90% of all people living with HIV knowing their status, 90% of all people diagnosed with HIV infection receiving ART, and 90% of all people receiving ART having robust viral suppression by 2020—aim to end the AIDS epidemic by 2030.
Why Was This Study Done?
Because early ART initiation both improves the health of HIV-positive individuals and reduces HIV transmission, the latest WHO guidelines (September 2015) recommend that people living with HIV should initiate ART upon diagnosis, regardless of their CD4 count. Previous WHO guidelines recommended initiating ART in certain populations based on CD4 count; for instance, the 2013 guidelines recommended adults living with HIV start ART only when their CD4 count fell below 500 cells/mm3 blood. Following the latest guidelines and meeting the UNAIDS targets will involve a rapid scale-up of ART, but are the financial resources available for this scale-up? Here, the researchers use mathematical modeling to estimate the numbers of people eligible for and receiving ART in 97 countries from 2015 to 2020 and the facility-level financial resources needed under three ART scale-up scenarios. Facility-level financial resources cover the costs of antiretroviral drugs, laboratory testing, and facility-level personnel and overhead (e.g., utilities, support staff, transportation, and other supplies), but not costs above the facility level or the costs of other services that are often integrated into ART provision. The facility-level ART costs are compared to the estimated financial resources available from domestic and external sources to assess the ART funding gap in the 97 countries.
What Did the Researchers Do and Find?
The researchers estimated current ART coverage levels and future treatment needs using country-specific epidemiological and demographic data for 97 countries. They estimated annual numbers of people eligible for and receiving treatment assuming that countries continued to follow their current criteria for treatment (scenario 1), universally adopted aspects of the WHO 2013 eligibility criteria (scenario 2), or expanded eligibility to meet the WHO 2015 guidelines and the 90-90-90 targets (scenario 3) while increasing the percentage of persons reached based on historical rates. Under scenario 1, 25.7 million adults and 1.57 million children living with HIV could receive ART by 2020. Under scenarios 2 and 3, 26.5 million and 30.4 million adults, respectively, and 1.53 million and 1.68 million children, respectively, could receive ART by 2020. The estimated facility-level financial resources needed for ART scale-up from 2015 to 2020 were US$45.8 billion, US$48.7 billion, and US$52.5 billion under scenarios 1, 2, and 3, respectively. Finally, the estimated gap over six years between the resources needed for ART scale-up and the domestic and external financial resources available ranged from US$19.8 billion to US$25.0 billion depending on the eligibility scenario and the level of ART support provided by PEPFAR (the U.S. President’s Emergency Plan for AIDS Relief) and the Global Fund to Fight AIDS, Tuberculosis and Malaria, two major external ART funding sources.
What Do These Findings Mean?
The accuracy of this study’s findings may be limited by the quality of country- and region-specific data, assumptions made about the funding available for ART, and the fact that only the facility-level costs of ART provision were considered. However, the estimates of the number of people receiving ART by 2020 suggest that countries are unlikely to meet the 90-90-90 treatment target (81% of people living with HIV on ART by 2020; that is, 90% of people living with HIV diagnosed and 90% of diagnosed patients receiving ART) unless countries expand ART access to all people living with HIV and rapidly increase coverage. Moreover, the estimated future resource needs for ART scale-up are large enough to threaten the sustainability of the global response to AIDS unless additional resources are made available through domestic or external financing sources or through efficiency gains. Thus, the researchers conclude, advances in technology and the introduction of new lower-cost antiretroviral regimens could be essential to allow more people to receive ART with the resources available.
Additional Information
This list of resources contains links that can be accessed when viewing the PDF on a device or via the online version of the article at http://dx.doi.org/10.1371/journal.pmed.1001907.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap also provides basic information about HIV/AIDS, summaries of recent research findings on HIV care and treatment, and personal stories about living with HIV/AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on universal access to ART, the 90-90-90 targets, and starting, monitoring, and switching ART; Avert also provides personal stories about living with HIV/AIDS
WHO provides information on all aspects of HIV/AIDS, including its 2013 ART guidelines and its early-released 2015 ART guidelines
The UNAIDS Fast-Track Strategy to End the AIDS Epidemic by 2030 provides up-to-date information about the AIDS epidemic, including progress towards universal access to ART; UNAIDS also provides detailed information about its 90-90-90 treatment targets
The Health Policy Project examines ways to make existing funds for ART go further and to maximize the effectiveness and efficiency of ART programs; information on PEPFAR and on the Global Fund to Fight AIDS, Tuberculosis and Malaria is available
doi:10.1371/journal.pmed.1001907
PMCID: PMC4658189  PMID: 26599990
3.  Antiretroviral Therapy for Prevention of Tuberculosis in Adults with HIV: A Systematic Review and Meta-Analysis 
PLoS Medicine  2012;9(7):e1001270.
In a systematic review and meta-analysis, Amitabh Suthar and colleagues investigate the association between antiretroviral therapy and the reduction in the incidence of tuberculosis in adults with HIV infection.
Background
Human immunodeficiency virus (HIV) infection is the strongest risk factor for developing tuberculosis and has fuelled its resurgence, especially in sub-Saharan Africa. In 2010, there were an estimated 1.1 million incident cases of tuberculosis among the 34 million people living with HIV worldwide. Antiretroviral therapy has substantial potential to prevent HIV-associated tuberculosis. We conducted a systematic review of studies that analysed the impact of antiretroviral therapy on the incidence of tuberculosis in adults with HIV infection.
Methods and Findings
PubMed, Embase, African Index Medicus, LILACS, and clinical trial registries were systematically searched. Randomised controlled trials, prospective cohort studies, and retrospective cohort studies were included if they compared tuberculosis incidence by antiretroviral therapy status in HIV-infected adults for a median of over 6 mo in developing countries. For the meta-analyses there were four categories based on CD4 counts at antiretroviral therapy initiation: (1) less than 200 cells/µl, (2) 200 to 350 cells/µl, (3) greater than 350 cells/µl, and (4) any CD4 count.
Eleven studies met the inclusion criteria. Antiretroviral therapy is strongly associated with a reduction in the incidence of tuberculosis in all baseline CD4 count categories: (1) less than 200 cells/µl (hazard ratio [HR] 0.16, 95% confidence interval [CI] 0.07 to 0.36), (2) 200 to 350 cells/µl (HR 0.34, 95% CI 0.19 to 0.60), (3) greater than 350 cells/µl (HR 0.43, 95% CI 0.30 to 0.63), and (4) any CD4 count (HR 0.35, 95% CI 0.28 to 0.44). There was no evidence of hazard ratio modification with respect to baseline CD4 count category (p = 0.20).
Conclusions
Antiretroviral therapy is strongly associated with a reduction in the incidence of tuberculosis across all CD4 count strata. Earlier initiation of antiretroviral therapy may be a key component of global and national strategies to control the HIV-associated tuberculosis syndemic.
Review Registration
International Prospective Register of Systematic Reviews CRD42011001209
Please see later in the article for the Editors' Summary.
Editors' Summary
Background
Tuberculosis—a contagious bacterial infection— is a global public-health problem. In 2010, 8.8 million people developed active tuberculosis and 1.4 million people died from the disease. Tuberculosis can be cured by taking powerful antibiotics regularly for several months, and between 1995 and 2010, 46 million people with tuberculosis were successfully treated using DOTS—a directly observed antibiotic regimen designed by the World Health Organization (WHO). Now, though, the HIV epidemic is compromising global tuberculosis control efforts. HIV-positive people are very susceptible to tuberculosis because HIV, the virus that causes AIDS, destroys the immune system cells (including CD4 lymphocytes) that normally combat tuberculosis. In 2010, 1.1 million of the new (incident) cases of tuberculosis were among the 34 million people living with HIV, and 350,000 people died of HIV-associated tuberculosis, making tuberculosis the leading cause of death among HIV-positive people. To tackle HIV-associated tuberculosis, which occurs mainly in developing countries, WHO now recommends that HIV and tuberculosis programs use collaborative approaches such as the Three I's for HIV/TB strategy—intensified tuberculosis case-finding among HIV-positive people, isoniazid preventative therapy for HIV-positive people without active tuberculosis, and (tuberculosis) infection control in healthcare facilities, social settings, and households.
Why Was This Study Done?
Despite progress in scaling up the Three I's for HIV/TB strategy, complementary interventions are still needed to prevent tuberculosis in HIV-positive people. Antiretroviral therapy (ART) lowers the viral load of people infected with HIV and restores their immune system function and could, therefore, prevent HIVassociated tuberculosis, in addition to treating HIV infection. WHO recommends ART for all HIV-positive adults with a CD4 count of less than 350 cells/μl of blood and for all HIVpositive, tuberculosis-positive individuals irrespective of their CD4 count. However, the evidence for ART's preventative impact on tuberculosis has not been systematically examined. Here, the researchers undertake a systematic review (a search that uses predefined criteria to identify all the research on a given topic) and a meta-analysis (a statistical method for combining the results of studies) to investigate the impact of ART initiated at various CD4 counts on the development of tuberculosis in HIV-positive adults in developing countries.
What Did the Researchers Do and Find?
The researchers found 11 studies that compared tuberculosis incidence by ART status in HIV-infected adults over periods longer than six months on average in developing countries and undertook meta-analyses of these studies based on four categories of CD4 count at ART initiation (less than 200 cells/μl, 200–350 cells/μl, greater than 350 cells/μl, and any CD4 count). For all these categories, ART was strongly associated with a reduction in the incidence of tuberculosis. For example, the meta-analysis of the two studies that reported on participants in whom ART was initiated at a CD4 count less than 200 cells/μl yielded a hazard ratio (HR) of 0.16. That is, study participants starting ART when their CD4 count was below 200 cells/μl were about one-sixth as likely to develop tuberculosis as participants not receiving ART. In the metaanalysis of all 11 studies, study participants receiving ART were about one-third as likely to develop tuberculosis as study participants receiving no ART, irrespective of their CD4 count (HR 0.35). Importantly, the CD4 count at which ART was initiated did not significantly alter the magnitude of ART's preventive effect on tuberculosis development.
What Do These Findings Mean?
These findings suggest that ART is strongly associated with a reduction in the incidence of tuberculosis in HIV-positive adults in developing countries, whatever the CD4 count at ART initiation. Because most of the studies in this meta-analysis were observational, these results do not show that ART causes a reduction in tuberculosis incidence—other unknown factors shared by the study participants who received ART may be responsible for their lower tuberculosis incidence. Moreover, factors such as variations in diagnostic methods among the studies included in this meta-analysis may have affected the accuracy of these findings. Nevertheless, the key finding that ART is associated with a significant reduction in tuberculosis cases among adults with CD4 counts greater than 350 cells//μl should be considered by healthcare providers, policymakers, and people living with HIV when weighing the benefits and risks of early ART initiation. It also suggests that early ART initiation (in combination with expanded HIV testing) could be a key component of future global and national strategies to control HIV-associated tuberculosis.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001270.
WHO provides information on all aspects of tuberculosis, including information on tuberculosis and HIV, on the Three I's for HIV/TB, and on ART for tuberculosis prevention (some information is in several languages)
The TB/HIV Working Group is part of the Stop TB Partnership, which is working toward tuberculosis elimination; patient stories about tuberculosis/HIV co-infection are also available on their site
The US Centers for Disease Control and Prevention has information about tuberculosis and about tuberculosis and HIV co-infection
The US National Institute of Allergy and Infectious Diseases also has detailed information on all aspects of tuberculosis including HIV-associated tuberculosis
Information is available from Avert, an international AIDS charity, on HIV-related tuberculosis (in English and Spanish), and from Aidsmap, a non-governmental organization, on HIV-associated tuberculosis
doi:10.1371/journal.pmed.1001270
PMCID: PMC3404110  PMID: 22911011
4.  Mortality of HIV-Infected Patients Starting Antiretroviral Therapy in Sub-Saharan Africa: Comparison with HIV-Unrelated Mortality 
PLoS Medicine  2009;6(4):e1000066.
Comparing mortality rates between patients starting HIV treatment and the general population in four African countries, Matthias Egger and colleagues find the gap decreases over time, especially with early treatment.
Background
Mortality in HIV-infected patients who have access to highly active antiretroviral therapy (ART) has declined in sub-Saharan Africa, but it is unclear how mortality compares to the non-HIV–infected population. We compared mortality rates observed in HIV-1–infected patients starting ART with non-HIV–related background mortality in four countries in sub-Saharan Africa.
Methods and Findings
Patients enrolled in antiretroviral treatment programmes in Côte d'Ivoire, Malawi, South Africa, and Zimbabwe were included. We calculated excess mortality rates and standardised mortality ratios (SMRs) with 95% confidence intervals (CIs). Expected numbers of deaths were obtained using estimates of age-, sex-, and country-specific, HIV-unrelated, mortality rates from the Global Burden of Disease project. Among 13,249 eligible patients 1,177 deaths were recorded during 14,695 person-years of follow-up. The median age was 34 y, 8,831 (67%) patients were female, and 10,811 of 12,720 patients (85%) with information on clinical stage had advanced disease when starting ART. The excess mortality rate was 17.5 (95% CI 14.5–21.1) per 100 person-years SMR in patients who started ART with a CD4 cell count of less than 25 cells/µl and World Health Organization (WHO) stage III/IV, compared to 1.00 (0.55–1.81) per 100 person-years in patients who started with 200 cells/µl or above with WHO stage I/II. The corresponding SMRs were 47.1 (39.1–56.6) and 3.44 (1.91–6.17). Among patients who started ART with 200 cells/µl or above in WHO stage I/II and survived the first year of ART, the excess mortality rate was 0.27 (0.08–0.94) per 100 person-years and the SMR was 1.14 (0.47–2.77).
Conclusions
Mortality of HIV-infected patients treated with combination ART in sub-Saharan Africa continues to be higher than in the general population, but for some patients excess mortality is moderate and reaches that of the general population in the second year of ART. Much of the excess mortality might be prevented by timely initiation of ART.
Please see later in the article for Editors' Summary
Editors' Summary
Background
Acquired immunodeficiency syndrome (AIDS) has killed more than 25 million people since 1981 and more than 30 million people (22 million in sub-Saharan Africa alone) are now infected with the human immunodeficiency virus (HIV), which causes AIDS. HIV destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-positive people died within ten years of infection. Then, in 1996, highly active antiretroviral therapy (ART)—combinations of powerful antiretroviral drugs—was developed and the life expectancy of HIV-infected people living in affluent countries improved dramatically. Now, in industrialized countries, all-cause mortality (death from any cause) among HIV-infected patients treated successfully with ART is similar to that of the general population and the mortality rate (the number of deaths in a population per year) among patients with HIV/AIDS is comparable to that among patients with diabetes and other chronic conditions.
Why Was This Study Done?
Unfortunately, combination ART is costly, so although HIV/AIDS quickly became a chronic disease in industrialized countries, AIDS deaths continued unabated among the millions of HIV-infected people living in low- and middle-income countries. Then, in 2003, governments, international agencies and funding bodies began to implement plans to increase ART coverage in developing countries. By the end of 2007, nearly three million people living with HIV/AIDS in these countries were receiving ART—nearly a third of the people who urgently need ART. In sub-Saharan Africa more than 2 million people now receive ART and mortality in HIV-infected patients who have access to ART is declining. However, no-one knows how mortality among HIV-infected people starting ART compares with non-HIV related mortality in sub-Saharan Africa. This information is needed to ensure that appropriate health services (including access to ART) are provided in this region. In this study, the researchers compare mortality rates among HIV-infected patients starting ART with non-HIV related mortality in the general population of four sub-Saharan countries.
What Did the Researchers Do and Find?
The researchers obtained estimates of the number of HIV-unrelated deaths and information about patients during their first two years on ART at five antiretroviral treatment programs in the Côte d'Ivoire, Malawi, South Africa, and Zimbabwe from the World Health Organization Global Burden of Disease (GBD) project and the International epidemiological Databases to Evaluate AIDS (IeDEA) initiative, respectively. They then calculated the excess mortality rates among the HIV-infected patients (the death rates in HIV-infected patients minus the national HIV-unrelated death rates) and the standardized mortality rate (SMR; the number of deaths among HIV-infected patients divided by the number of HIV-unrelated deaths in the general population). The excess mortality rate among HIV-infected people who started ART when they had a low CD4 cell count and clinically advanced disease was 17.5 per 100 person-years of follow-up. For HIV-infected people who started ART with a high CD4 cell count and early disease, the excess mortality rate was 1.0 per 100 person-years. The SMRs over two years of ART for these two groups of HIV-infected patients were 47.1 and 3.4, respectively. Finally, patients who started ART with a high CD4 cell count and early disease who survived the first year of ART had an excess mortality of only 0.27 per 100 person-years and an SMR over two years follow-up of only 1.14.
What Do These Findings Mean?
These findings indicate that mortality among HIV-infected people during the first two years of ART is higher than in the general population in these four sub-Saharan countries. However, for patients who start ART when they have a high CD4 count and clinically early disease, the excess mortality is moderate and similar to that associated with diabetes. Because the researchers compared the death rates among HIV-infected patients with estimates of national death rates rather than with estimates of death rates for the areas where the ART programs were located, these findings may not be completely accurate. Nevertheless, these findings support further expansion of strategies that increase access to ART in sub-Saharan Africa and suggest the excess mortality among HIV-infected patients in this region might be largely prevented by starting ART before an individual's HIV infection has progressed to advanced stages.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000066.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS including HIV and AIDS in Africa, providing AIDS drug treatment for millions, and on the stages of HIV infection
The World Health Organization provides information about universal access to HIV treatment and about the Global Burden of Disease project (in several languages)
More information about the International epidemiological Databases to evaluate AIDS initiative is available on the IeDEA Web site
doi:10.1371/journal.pmed.1000066
PMCID: PMC2667633  PMID: 19399157
5.  The Impact of Monitoring HIV Patients Prior to Treatment in Resource-Poor Settings: Insights from Mathematical Modelling 
PLoS Medicine  2008;5(3):e53.
Background
The roll-out of antiretroviral treatment (ART) in developing countries concentrates on finding patients currently in need, but over time many HIV-infected individuals will be identified who will require treatment in the future. We investigated the potential influence of alternative patient management and ART initiation strategies on the impact of ART programmes in sub-Saharan Africa.
Methods and Findings
We developed a stochastic mathematical model representing disease progression, diagnosis, clinical monitoring, and survival in a cohort of 1,000 hypothetical HIV-infected individuals in Africa. If individuals primarily enter ART programmes when symptomatic, the model predicts that only 25% will start treatment and, on average, 6 life-years will be saved per person treated. If individuals are recruited to programmes while still healthy and are frequently monitored, and CD4+ cell counts are used to help decide when to initiate ART, three times as many are expected to be treated, and average life-years saved among those treated increases to 15. The impact of programmes can be improved further by performing a second CD4+ cell count when the initial value is close to the threshold for starting treatment, maintaining high patient follow-up rates, and prioritising monitoring the oldest (≥ 35 y) and most immune-suppressed patients (CD4+ cell count ≤ 350). Initiating ART at higher CD4+ cell counts than WHO recommends leads to more life-years saved, but disproportionately more years spent on ART.
Conclusions
The overall impact of ART programmes will be limited if rates of diagnosis are low and individuals enter care too late. Frequently monitoring individuals at all stages of HIV infection and using CD4 cell count information to determine when to start treatment can maximise the impact of ART.
Using a stochastic model based on data from Africa, Timothy Hallett and colleagues find that starting HIV treatment based on regular CD4 monitoring, rather than on symptoms, would substantially increase survival.
Editors' Summary
Background.
Acquired immunodeficiency syndrome (AIDS) has killed more than 25 million people since the first case in 1981, and about 33 million people are currently infected with the human immunodeficiency virus (HIV), which causes AIDS. HIV destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-positive individuals died within 10 years but in 1996, combination antiretroviral therapy (ART)—a mixture of powerful but expensive antiretroviral drugs—was developed. For HIV-positive people living in affluent, developed countries who could afford ART, AIDS then became a chronic disease, but for those living in low- and middle-income countries it remained a death sentence—ART was too expensive. In 2003, this lack of access to ART was declared a global health emergency and governments, international organizations, and funding bodies began to implement plans to increase ART coverage in developing countries.
Why Was This Study Done?
The roll-out of ART in developing countries has concentrated so far on finding HIV-positive people who currently need treatment. In developing countries, these are often individuals who have AIDS-related symptoms such as recurrent severe bacterial infections. But healthy people are also being diagnosed as HIV positive during voluntary testing and at antenatal clinics. How should these HIV-positive but symptom-free individuals be managed? Should regular health-monitoring appointments be scheduled for them and when should ART be initiated? Management decisions like these will determine how well patients do when they eventually start ART, as well as the demand for ART and other health-care services. The full range of alternative patient management strategies cannot be tested in clinical trials—it would be unethical—but public-health officials need an idea of their relative effectiveness in order to use limited resources wisely. In this study, therefore, the researchers use mathematical modeling to investigate the impact of alternative patient management and ART initiation strategies on the impact of ART programs in resource-poor settings.
What Did the Researchers Do and Find?
The researchers' mathematical model, which includes data on disease progression collected in Africa, simulates disease progression in a group (cohort) of 1,000 HIV-infected adults. It tracks these individuals from infection, through diagnosis and clinical monitoring, and into treatment and predicts how many will receive ART and their length of survival under different management scenarios and ART initiation rules. The model predicts that if HIV-positive individuals receive ART only when they have AIDS-related symptoms, only a quarter of them will ever start ART and the average life-years saved per person treated will be 6 years (that is, they will live 6 years longer than they would have done without treatment). If individuals are recruited to ART programs when they are healthy and are frequently monitored using CD4 cell counts to decide when to start ART, three-quarters of the cohort will be treated and 15 life-years will be saved per person treated. The impact of ART programs will be increased further, the model predicts, by preferentially monitoring people who are more than 35 years old and the most immunosuppressed individuals. Finally, strategies that measure CD4 cells frequently will save more life-years because ART is more likely to be started before the immune system is irreversibly damaged. Importantly for resource-poor settings, these strategies also save more life-years per year on ART.
What Do These Findings Mean?
As with all mathematical models, the accuracy of these predictions depends on the assumptions built into the model and the reliability of the data fed into it. Also, this model does not estimate the costs of the various management options, something that will need to be done to ensure effective allocation of limited resources. Nevertheless, these findings provide several general clues about how ART programs should be implemented in poor countries to maximize their effects. Early diagnosis of infections, regular monitoring of patients, and using CD4 cell counts to decide when to initiate ART should all help to improve the number of life-years saved by ART. In other words, the researchers conclude, effectively managing individuals at all stages of HIV infection is essential to maximize the impact of ART.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/doi:10.1371/journal.pmed.0050053.
Information from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS.
Information from the US Centers for Disease Control and Prevention on global HIV/AIDS topics (in English and Spanish)
HIV InSite, comprehensive and up-to-date information on all aspects of HIV/AIDS from the University of California, San Francisco
Information from Avert, an international AIDS charity, on HIV and AIDS in Africa and on HIV/AIDS treatment and care, including universal access to ART
Progress toward universal access to HIV/AIDS treatment, the latest report from the World Health Organization (available in several languages)
Guidelines for antiretroviral therapy in adults and adolescents are provided by the World Health Organization and by the US Department of Health and Human Services
doi:10.1371/journal.pmed.0050053
PMCID: PMC2265759  PMID: 18336064
6.  Gender Differences in Survival among Adult Patients Starting Antiretroviral Therapy in South Africa: A Multicentre Cohort Study 
PLoS Medicine  2012;9(9):e1001304.
Morna Cornell and colleagues investigate differences in mortality for HIV-positive men and women on antiretroviral therapy in South Africa.
Background
Increased mortality among men on antiretroviral therapy (ART) has been documented but remains poorly understood. We examined the magnitude of and risk factors for gender differences in mortality on ART.
Methods and Findings
Analyses included 46,201 ART-naïve adults starting ART between January 2002 and December 2009 in eight ART programmes across South Africa (SA). Patients were followed from initiation of ART to outcome or analysis closure. The primary outcome was mortality; secondary outcomes were loss to follow-up (LTF), virologic suppression, and CD4+ cell count responses. Survival analyses were used to examine the hazard of death on ART by gender. Sensitivity analyses were limited to patients who were virologically suppressed and patients whose CD4+ cell count reached >200 cells/µl. We compared gender differences in mortality among HIV+ patients on ART with mortality in an age-standardised HIV-negative population.
Among 46,201 adults (65% female, median age 35 years), during 77,578 person-years of follow-up, men had lower median CD4+ cell counts than women (85 versus 110 cells/µl, p<0.001), were more likely to be classified WHO stage III/IV (86 versus 77%, p<0.001), and had higher mortality in crude (8.5 versus 5.7 deaths/100 person-years, p<0.001) and adjusted analyses (adjusted hazard ratio [AHR] 1.31, 95% CI 1.22–1.41). After 36 months on ART, men were more likely than women to be truly LTF (AHR 1.20, 95% CI 1.12–1.28) but not to die after LTF (AHR 1.04, 95% CI 0.86–1.25). Findings were consistent across all eight programmes. Virologic suppression was similar by gender; women had slightly better immunologic responses than men. Notably, the observed gender differences in mortality on ART were smaller than gender differences in age-standardised death rates in the HIV-negative South African population. Over time, non-HIV mortality appeared to account for an increasing proportion of observed mortality. The analysis was limited by missing data on baseline HIV disease characteristics, and we did not observe directly mortality in HIV-negative populations where the participating cohorts were located.
Conclusions
HIV-infected men have higher mortality on ART than women in South African programmes, but these differences are only partly explained by more advanced HIV disease at the time of ART initiation, differential LTF and subsequent mortality, and differences in responses to treatment. The observed differences in mortality on ART may be best explained by background differences in mortality between men and women in the South African population unrelated to the HIV/AIDS epidemic.
Please see later in the article for the Editors' Summary.
Editors' Summary
Background
About 34 million people (most living in low- and middle-income countries) are currently infected with HIV, the virus that causes AIDS. HIV destroys CD4 lymphocytes and other immune system cells, leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected people died within 10 years of becoming infected. Then, in 1996, antiretroviral therapy (ART)—cocktails of drugs that keep HIV in check—became available. For people living in affluent countries, HIV/AIDS became a chronic condition. However, ART was expensive and, for people living in poorer countries, HIV/AIDS remained a fatal illness. In 2003, this situation was declared a global emergency, and governments and international agencies began to implement plans to increase ART coverage in resource-limited countries. Since then, ART programs in these countries have grown rapidly. In South Africa, for example, about 52% of the 3.14 million adults in need of ART were receiving an ART regimen recommended by the World Health Organization by the end of 2010.
Why Was This Study Done?
The outcomes of ART programs in resource-limited countries need to be evaluated thoroughly so that these programs can be optimized. One area of concern to ART providers is that of gender differences in survival among patients receiving treatment. In sub-Saharan Africa, for example, men are more likely to die than women while receiving ART. This gender difference in mortality may arise because men initiating ART in many African ART programs have more advanced HIV disease than women (early ART initiation is associated with better outcomes than late initiation) or because men are more likely to be lost to follow-up than women (failure to continue treatment is associated with death). Other possible explanations for gender differentials in mortality on ART include gender differences in immunologic and virologic responses to treatment (increased numbers of immune system cells and reduced amounts of virus in the blood, respectively). In this multicenter cohort study, the researchers examine the size of, and risk factors for, gender differences in mortality on ART in South Africa by examining data collected from adults starting ART at International Epidemiologic Databases to Evaluate AIDS South Africa (IeDEA-SA) collaboration sites.
What Did the Researchers Do and Find?
The researchers analyzed data collected from 46,201 ART-naïve adults who started ART between 2002 and 2009 in eight IeDEA-SA ART programs. At ART initiation, men had a lower CD4 count on average and were more likely to have advanced HIV disease than women. During the study, after allowing for factors likely to affect mortality such as HIV disease stage at initiation, men on ART had a 31% higher risk of dying than women. Men were more likely to be lost to follow-up than women, but men and women who were lost to follow-up were equally likely to die. Women had a slightly better immunological response to ART than men but virologic suppression was similar in both genders. Importantly, in analyses of mortality limited to individuals who were virologically suppressed at 12 months and to patients who had a good immunological response to ART, men still had a higher risk of death than women. However, the gender differences in mortality on ART were smaller than the gender differences in age-standardized mortality in the HIV-negative South African population.
What Do These Findings Mean?
These analyses show that among South African patients initiating ART between 2002 and 2009, men were more likely to die than women but that this gender difference in mortality on ART cannot be completely explained by gender differences in baseline characteristics, loss to follow-up, or virologic and/or immunologic responses. Instead, the observed gender differences in mortality can best be explained by background gender differences in mortality in the whole South African population. Because substantial amounts of data were missing in this study (for example, HIV disease stage was not available for all the patients), these findings need to be interpreted cautiously. Moreover, similar studies need to be done in other settings to investigate whether they are generalizable to the South African national ART program and to other countries. If confirmed, however, these findings suggest that the root causes of gender differences in mortality on ART may be unrelated to HIV/AIDS or to the characteristics of ART programs.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001304.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
Information on the treatment of HIV/AIDS in South Africa is available from the Southern African HIV Clinicians Society
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on HIV/AIDS treatment and care, and on HIV/AIDS in South Africa (in English and Spanish)
WHO provides information about universal access to AIDS treatment (in several languages); its 2010 ART guidelines can be downloaded
Information about the IeDEA-SA collaboration is available
The Treatment Action Campaign provides information on antiretroviral therapy and South African HIV statistics
Patient stories about living with HIV/AIDS are available through Avert; the nonprofit website Healthtalkonline also provides personal stories about living with HIV, including stories about taking anti-HIV drugs and the challenges of anti-HIV drugs
doi:10.1371/journal.pmed.1001304
PMCID: PMC3433409  PMID: 22973181
7.  Cotrimoxazole Prophylaxis Discontinuation among Antiretroviral-Treated HIV-1-Infected Adults in Kenya: A Randomized Non-inferiority Trial 
PLoS Medicine  2016;13(1):e1001934.
Background
Cotrimoxazole (CTX) prophylaxis is recommended by the World Health Organization (WHO) for HIV-1-infected individuals in settings with high infectious disease prevalence. The WHO 2006 guidelines were developed prior to the scale-up of antiretroviral therapy (ART). The threshold for CTX discontinuation following ART is undefined in resource-limited settings.
Methods and Findings
Between 1 February 2012 and 30 September 2013, we conducted an unblinded non-inferiority randomized controlled trial of CTX prophylaxis cessation versus continuation among HIV-1-infected adults on ART for ≥18 mo with CD4 count > 350 cells/mm3 in a malaria-endemic region in Kenya. Participants were randomized and followed up at 3-mo intervals for 12 mo. The primary endpoint was a composite of morbidity (malaria, pneumonia, and diarrhea) and mortality. Incidence rate ratios (IRRs) were estimated using Poisson regression.
Among 538 ART-treated adults screened, 500 were enrolled and randomized, 250 per arm. Median age was 40 y, 361 (72%) were women, and 442 (88%) reported insecticide-treated bednet use. Combined morbidity/mortality was significantly higher in the CTX discontinuation arm (IRR = 2.27, 95% CI 1.52–3.38; p < 0.001), driven by malaria morbidity. There were 34 cases of malaria, with 33 in the CTX discontinuation arm (IRR = 33.02, 95% CI 4.52–241.02; p = 0.001). Diarrhea and pneumonia rates did not differ significantly between arms (IRR = 1.36, 95% CI 0.82–2.27, and IRR = 1.43, 95% CI 0.54–3.75, respectively). Study limitations include a lack of placebo and a lower incidence of morbidity events than expected.
Conclusions
CTX discontinuation among ART-treated, immune-reconstituted adults in a malaria-endemic region resulted in increased incidence of malaria but not pneumonia or diarrhea. Malaria endemicity may be the most relevant factor to consider in the decision to stop CTX after ART-induced immune reconstitution in regions with high infectious disease prevalence. These data support the 2014 WHO CTX guidelines.
Trial registration
ClinicalTrials.gov NCT01425073
In a randomized controlled non-inferiority trial, Christina Polyak and colleagues assess whether CTX prophylaxis remains important among HIV+ adults on ART in a malaria-endemic setting.
Editors' Summary
Background
AIDS has killed 39 million people over the past three decades, and 35 million people (mostly living in resource-limited countries) are currently infected with HIV, the virus that causes AIDS. HIV, which is usually transmitted through unprotected sex with an infected individual, gradually destroys CD4 lymphocytes and other immune system cells. Because destruction of the immune system leaves HIV-infected individuals susceptible to “opportunistic” infections, early in the AIDS epidemic, most HIV-positive individuals died within ten years of infection. In 1996, effective antiretroviral therapy (ART)—drug regimens that stop HIV replicating and allow the immune system to recover its ability to fight infections—became available. For people living in affluent countries, HIV/AIDS became a chronic condition, but because ART was expensive, HIV/AIDS remained fatal in resource-limited countries. In 2003, the international community began to work towards achieving universal access to ART. Now, at least a third of people living with HIV have access to ART, and the global mortality (death) rate from HIV/AIDS is falling.
Why Was This Study Done?
To prevent opportunistic infections, the World Health Organization (WHO) recommends cotrimoxazole (CTX) prophylaxis for HIV-infected individuals. CTX is a combination of two antimicrobial drugs that is active against a range of bacterial, fungal, and parasitic infections; prophylactic antimicrobials are taken to prevent infection. CTX decreases morbidity (illness) and mortality among HIV-infected individuals primarily by reducing the rates of malaria, pneumonia, diarrhea, and severe bacterial infections. The 2006 WHO guidelines for CTX prophylaxis recommend that, in resource-limited countries, HIV-infected patients whose CD4 count is ≤350 cells/mm3 blood should take CTX and that, in settings with a high prevalence of HIV infection and limited health infrastructure, all HIV-infected adults should take CTX. However, these guidelines were developed before access to ART was scaled-up, and CTX prophylaxis has risks (for example, drug toxicity) as well as benefits. In this unblinded non-inferiority randomized controlled trial, the researchers investigate the effects of CTX discontinuation among ART-treated HIV-infected adults in Kenya. A randomized controlled trial compares the outcomes of individuals randomly assigned to different treatments; in an unblinded trial, everyone involved in the trial knows who is taking which treatment; a non-inferiority trial investigates whether one treatment is not worse than another treatment.
What Did the Researchers Do and Find?
The researchers enrolled 500 HIV-infected adults living in a malaria-endemic region of Kenya (an area where malaria is always present) who had been treated with ART for ≥18 months, who had a CD4 count of >350 cells/mm3, and who were taking CTX. Half the participants continued to take CTX; the remainder stopped taking CTX. After 12 months of follow-up, the combined rate of morbidity (malaria, pneumonia, and diarrhea) and mortality was significantly higher in the CTX discontinuation arm than in the CTX continuation arm (a significant difference is one that is unlikely to have happened by chance). The difference in this primary outcome between the trial arms was driven by malaria morbidity—there were 33 cases of malaria in the CTX discontinuation arm but only one case in the CTX continuation arm. By contrast, the rates of pneumonia and diarrhea did not differ significantly between the trial arms.
What Do These Findings Mean?
Because the difference between the two trial arms in terms of the primary endpoint was greater than the researchers’ predefined non-inferiority limit, these findings suggest that CTX discontinuation is inferior to CTX continuation among ART-treated, immune-reconstituted HIV-infected adults living in a malaria-endemic region. The accuracy of these findings may be affected by the lack of blinding—the clinicians’ care decisions and the patients’ threshold for seeking care may have been influenced by their knowledge of their trial arm assignment. Overall, however, these findings suggest that malaria endemicity should be considered when making decisions about whether to stop CTX after ART-driven immune reconstitution. Indeed, in December 2014, following the release of preliminary data from this trial and the completion of an independent trial on CTX discontinuation, WHO issued supplemental guidelines on CTX prophylaxis. These state that CTX prophylaxis can be discontinued for HIV-infected adults who are clinically stable on ART and have evidence of immune recovery and viral suppression but recommend that CTX prophylaxis be continued regardless of CD4 cell count or HIV/AIDS clinical stage in settings where malaria is endemic and/or severe bacterial infections are common.
Additional Information
This list of resources contains links that can be accessed when viewing the PDF on a device or via the online version of the article at http://dx.doi.org/10.1371/journal.pmed.1001934.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, summaries of recent research findings on HIV care and treatment, information on opportunistic infections and on CTX prophylaxis, and personal stories about living with HIV/AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV/AIDS in Kenya, on ART, and on opportunistic infections and CTX prophylaxis: Avert also provides personal stories about living with HIV/AIDS
WHO provides information on all aspects of HIV/AIDS, including its 2013 guidelines on using ART to treat HIV infection and its December 2014 supplement to these guidelines, which contains updated recommendations on CTX prophylaxis; a factsheet about CTX prophylaxis is also available
The 2015 World AIDS Day Report provides up-to-date information about the AIDS epidemic, including progress towards universal access to ART
More information about this trial is available
doi:10.1371/journal.pmed.1001934
PMCID: PMC4701407  PMID: 26731191
8.  HIV Treatment as Prevention: Systematic Comparison of Mathematical Models of the Potential Impact of Antiretroviral Therapy on HIV Incidence in South Africa 
PLoS Medicine  2012;9(7):e1001245.
Background
Many mathematical models have investigated the impact of expanding access to antiretroviral therapy (ART) on new HIV infections. Comparing results and conclusions across models is challenging because models have addressed slightly different questions and have reported different outcome metrics. This study compares the predictions of several mathematical models simulating the same ART intervention programmes to determine the extent to which models agree about the epidemiological impact of expanded ART.
Methods and Findings
Twelve independent mathematical models evaluated a set of standardised ART intervention scenarios in South Africa and reported a common set of outputs. Intervention scenarios systematically varied the CD4 count threshold for treatment eligibility, access to treatment, and programme retention. For a scenario in which 80% of HIV-infected individuals start treatment on average 1 y after their CD4 count drops below 350 cells/µl and 85% remain on treatment after 3 y, the models projected that HIV incidence would be 35% to 54% lower 8 y after the introduction of ART, compared to a counterfactual scenario in which there is no ART. More variation existed in the estimated long-term (38 y) reductions in incidence. The impact of optimistic interventions including immediate ART initiation varied widely across models, maintaining substantial uncertainty about the theoretical prospect for elimination of HIV from the population using ART alone over the next four decades. The number of person-years of ART per infection averted over 8 y ranged between 5.8 and 18.7. Considering the actual scale-up of ART in South Africa, seven models estimated that current HIV incidence is 17% to 32% lower than it would have been in the absence of ART. Differences between model assumptions about CD4 decline and HIV transmissibility over the course of infection explained only a modest amount of the variation in model results.
Conclusions
Mathematical models evaluating the impact of ART vary substantially in structure, complexity, and parameter choices, but all suggest that ART, at high levels of access and with high adherence, has the potential to substantially reduce new HIV infections. There was broad agreement regarding the short-term epidemiologic impact of ambitious treatment scale-up, but more variation in longer term projections and in the efficiency with which treatment can reduce new infections. Differences between model predictions could not be explained by differences in model structure or parameterization that were hypothesized to affect intervention impact.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Following the first reported case of AIDS in 1981, the number of people infected with HIV, the virus that causes AIDS, increased rapidly. In recent years, the number of people becoming newly infected has declined slightly, but the virus continues to spread at unacceptably high levels. In 2010 alone, 2.7 million people became HIV-positive. HIV, which is usually transmitted through unprotected sex, destroys CD4 lymphocytes and other immune system cells, leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, half of HIV-infected people died within eleven years of infection. Then, in 1996, antiretroviral therapy (ART) became available, and, for people living in affluent countries, HIV/AIDS gradually became considered a chronic condition. But because ART was expensive, for people living in developing countries HIV/AIDS remained a fatal condition. Roll-out of ART in developing countries first started in the early 2000s. In 2006, the international community set a target of achieving universal ART coverage by 2010. Although this target has still not been reached, by the end of 2010, 6.6 million of the estimated 15 million people in need of ART in developing countries were receiving ART.
Why Was This Study Done?
Several studies suggest that ART, in addition to reducing illness and death among HIV-positive people, reduces HIV transmission. Consequently, there is interest in expanding the provision of ART as a strategy for reducing the spread of HIV (“HIV treatment as prevention"), particularly in sub-Saharan Africa, where one in 20 adults is HIV-positive. It is important to understand exactly how ART might contribute to averting HIV transmission. Several mathematical models that simulate HIV infection and disease progression have been developed to investigate the impact of expanding access to ART on the incidence of HIV (the number of new infections occurring in a population over a year). But, although all these models predict that increased ART coverage will have epidemiologic (population) benefits, they vary widely in their estimates of the magnitude of these benefits. In this study, the researchers systematically compare the predictions of 12 mathematical models of the HIV epidemic in South Africa, simulating the same ART intervention programs to determine the extent to which different models agree about the impact of expanded ART.
What Did the Researchers Do and Find?
The researchers invited groups who had previously developed mathematical models of the epidemiological impact of expanded access to ART in South Africa to participate in a systematic comparison exercise in which their models were used to simulate ART scale-up scenarios in which the CD4 count threshold for treatment eligibility, access to treatment, and retention on treatment were systematically varied. To exclude variation resulting from different model assumptions about the past and current ART program, it was assumed that ART is introduced into the population in the year 2012, with no treatment provision prior to this, and interventions were evaluated in comparison to an artificial counterfactual scenario in which no treatment is provided. A standard scenario based on the World Health Organization's recommended threshold for initiation of ART, although unrepresentative of current provision in South Africa, was used to compare the models. In this scenario, 80% of HIV-infected individuals received treatment, they started treatment on average a year after their CD4 count dropped below 350 cells per microliter of blood, and 85% remained on treatment after three years. The models predicted that, with a start point of 2012, the HIV incidence would be 35%–54% lower in 2020 and 32%–74% lower in 2050 compared to a counterfactual scenario where there was no ART. Estimates of the number of person-years of ART needed per infection averted (the efficiency with which ART reduced new infections) ranged from 6.3–18.7 and from 4.5–20.2 over the periods 2012–2020 and 2012–2050, respectively. Finally, estimates of the impact of ambitious interventions (for example, immediate treatment of all HIV-positive individuals) varied widely across the models.
What Do These Findings Mean?
Although the mathematical models used in this study had different characteristics, all 12 predict that ART, at high levels of access and adherence, has the potential to reduce new HIV infections. However, although the models broadly agree about the short-term epidemiologic impact of treatment scale-up, their longer-term projections (including whether ART alone can eliminate HIV infection) and their estimates of the efficiency with which ART can reduce new infections vary widely. Importantly, it is possible that all these predictions will be wrong—all the models may have excluded some aspect of HIV transmission that will be found in the future to be crucial. Finally, these findings do not aim to indicate which specific ART interventions should be used to reduce the incidence of HIV. Rather, by comparing the models that are being used to investigate the feasibility of “HIV treatment as prevention," these findings should help modelers and policy-makers think critically about how the assumptions underlying these models affect the models' predictions.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001245.
This study is part of the July 2012 PLoS Medicine Collection, Investigating the Impact of Treatment on New HIV Infections
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on HIV/AIDS treatment and care, on HIV treatment as prevention, and on HIV/AIDS in South Africa (in English and Spanish)
The World Health Organization provides information about universal access to AIDS treatment (in English, French, and Spanish); its 2010 ART guidelines can be downloaded
The HIV Modelling Consortium aims to improve scientific support for decision-making by coordinating mathematical modeling of the HIV epidemic
Patient stories about living with HIV/AIDS are available through Avert; the charity website Healthtalkonline also provides personal stories about living with HIV, including stories about taking anti-HIV drugs and the challenges of anti-HIV drugs
doi:10.1371/journal.pmed.1001245
PMCID: PMC3393664  PMID: 22802730
9.  Causes and Determinants of Mortality in HIV-Infected Adults With Tuberculosis: An Analysis From the CAMELIA ANRS 1295-CIPRA KH001 Randomized Trial 
We report causes of 149 deaths that occurred among 661 HIV-infected adults with tuberculosis in a trial assessing the optimal timing for antiretroviral therapy (ART) initiation. Timing of ART, early interruption of cotrimoxazole, and tuberculosis-related factors were determinants of mortality.
Background. Shortening the interval between antituberculosis treatment onset and initiation of antiretroviral therapy (ART) reduces mortality in severely immunocompromised human immunodeficiency virus (HIV)–infected patients with tuberculosis. A better understanding of causes and determinants of death may lead to new strategies to further enhance survival.
Methods. We assessed mortality rates, causes of death, and factors of mortality in Cambodian HIV-infected adults with CD4 count ≤200 cells/µL and tuberculosis, randomized to initiate ART either 2 weeks (early ART) or 8 weeks (late ART) after tuberculosis treatment onset in the CAMELIA clinical trial.
Results. Six hundred sixty-one patients enrolled contributed to 1366.1 person-years of follow-up; 149 (22.5%) died. There were 8.3 deaths per 100 person-years (95% confidence interval [CI], 6.4–10.7) in the early-ART group and 13.8 deaths per 100 person-years (95% CI, 11.2–16.9) in the late-ART group (P = .002). Tuberculosis was the primary cause of death (28%), followed by other HIV-associated conditions (19%). Factors independently associated with mortality in the first 26 weeks were the age, body mass index, hemoglobin, interrupted or ineffective tuberculosis treatment before identification of drug resistance, disseminated tuberculosis, and nontuberculous mycobacterial disease. After 50 weeks in the trial, the most frequent causes of death were non-HIV related or tuberculosis related, including drug toxicity; factors associated with mortality were late ART, loss to follow-up, and absence of cotrimoxazole prophylaxis.
Conclusions. Despite ART introduction, mortality remained high, with tuberculosis as the leading cause of death. Reducing tuberculosis-related mortality remains a challenge in resource-limited settings and requires innovative strategies.
Clinical Trials Registration. NCT00226434.
doi:10.1093/cid/ciu283
PMCID: PMC4155439  PMID: 24759827
tuberculosis; HIV; mortality; cause of death; adult
10.  Mortality in Patients with HIV-1 Infection Starting Antiretroviral Therapy in South Africa, Europe, or North America: A Collaborative Analysis of Prospective Studies 
PLoS Medicine  2014;11(9):e1001718.
Analyzing survival in HIV treatment cohorts, Andrew Boulle and colleagues find mortality rates in South Africa comparable to or better than those in North America by 4 years after starting antiretroviral therapy.
Please see later in the article for the Editors' Summary
Background
High early mortality in patients with HIV-1 starting antiretroviral therapy (ART) in sub-Saharan Africa, compared to Europe and North America, is well documented. Longer-term comparisons between settings have been limited by poor ascertainment of mortality in high burden African settings. This study aimed to compare mortality up to four years on ART between South Africa, Europe, and North America.
Methods and Findings
Data from four South African cohorts in which patients lost to follow-up (LTF) could be linked to the national population register to determine vital status were combined with data from Europe and North America. Cumulative mortality, crude and adjusted (for characteristics at ART initiation) mortality rate ratios (relative to South Africa), and predicted mortality rates were described by region at 0–3, 3–6, 6–12, 12–24, and 24–48 months on ART for the period 2001–2010. Of the adults included (30,467 [South Africa], 29,727 [Europe], and 7,160 [North America]), 20,306 (67%), 9,961 (34%), and 824 (12%) were women. Patients began treatment with markedly more advanced disease in South Africa (median CD4 count 102, 213, and 172 cells/µl in South Africa, Europe, and North America, respectively). High early mortality after starting ART in South Africa occurred mainly in patients starting ART with CD4 count <50 cells/µl. Cumulative mortality at 4 years was 16.6%, 4.7%, and 15.3% in South Africa, Europe, and North America, respectively. Mortality was initially much lower in Europe and North America than South Africa, but the differences were reduced or reversed (North America) at longer durations on ART (adjusted rate ratios 0.46, 95% CI 0.37–0.58, and 1.62, 95% CI 1.27–2.05 between 24 and 48 months on ART comparing Europe and North America to South Africa). While bias due to under-ascertainment of mortality was minimised through death registry linkage, residual bias could still be present due to differing approaches to and frequency of linkage.
Conclusions
After accounting for under-ascertainment of mortality, with increasing duration on ART, the mortality rate on HIV treatment in South Africa declines to levels comparable to or below those described in participating North American cohorts, while substantially narrowing the differential with the European cohorts.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
AIDS has killed about 36 million people since the first recorded case of the disease in 1981, and a similar number of people (including 25 million living in sub-Saharan Africa) are currently infected with HIV, the virus that causes AIDS. HIV destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other serious infections. Early in the AIDS epidemic, HIV-positive people usually died within 10 years of becoming infected. In 1996, effective antiretroviral therapy (ART) became available and, for people living in high-income countries, HIV infection became a chronic condition. But ART was expensive, so HIV/AIDS remained largely untreated and fatal in resource-limited countries. Then, in 2003, the international community began to work towards achieving universal access to ART. By the end of 2012, nearly two-thirds of HIV-positive people (nearly 10 million individuals) living in low- and middle-income countries who were eligible for treatment because their CD4 cell count had fallen below 350/mm3 blood or because they had developed an AIDS-defining condition were receiving treatment.
Why Was This Study Done?
It is known that a larger proportion of HIV-positive patients starting ART die during the first year of treatment in sub-Saharan Africa than in Europe and North America. This difference arises in part because patients in resource-limited settings tend to have lower CD4 counts when they start treatment than patients in wealthy countries. However, the lack of reliable data on mortality (death) in resource-limited settings has made it hard to compare longer-term outcomes in different settings. Information on the long-term outcomes of HIV-positive patients receiving ART in resource-limited countries is needed to guide the development of appropriate health systems and treatment regimens in these settings. In this collaborative analysis of prospective cohort studies, the researchers compare mortality up to 4 years on ART in South Africa, Europe, and North America. A prospective cohort study follows a group of individuals over time to see whether differences in specific characteristics at the start of the study affect subsequent outcomes. A collaborative analysis combines individual patient data from several studies.
What Did the Researchers Do and Find?
The researchers combined data from four South Africa cohorts of HIV-positive patients starting ART included in the International Epidemiologic Databases to Evaluate AIDS South African (IeDEA-SA) collaboration with data from six North American cohorts and nine European cohorts included in the ART Cohort Collaboration (ART-CC). The South African cohorts were chosen because unusually for studies undertaken in countries in sub-Saharan Africa the vital status of patients (whether they had died) who had been lost to follow-up in these cohorts could be obtained from the national population register. Patients in South Africa began treatment with more advanced disease (indicated by a lower average CD4 count) than patients in Europe or North America. Notably, high early mortality after starting ART in South Africa occurred mainly in patients starting ART with a CD4 count below 50 cells/mm3. The cumulative mortality after 4 years of ART was 16.6%, 4.7%, and 15.3% in South Africa, Europe, and North America, respectively. After adjusting for patient characteristics at ART initiation, the mortality rate among patients beginning ART was initially lower in Europe and North American than in South Africa. However, although the adjusted mortality rate in Europe remained lower than the rate in South Africa, the rate in North America was higher than that in South Africa between 24 and 48 months on ART.
What Do These Findings Mean?
Although the linkage to national vital registration systems (databases of births and deaths) undertaken in this collaborative analysis is likely to have greatly reduced bias due to under-ascertainment of mortality, the accuracy of these findings may still be limited by differences in how this linkage was undertaken in different settings. Nevertheless, these findings suggest that mortality among HIV-infected patients receiving ART in South Africa, although initially higher than in Europe and North America, rapidly declines with increasing duration on ART and, after 4 years of treatment, approaches the rate seen in high-income settings. Intriguingly, these findings also highlight the relatively higher late mortality in North America compared to either Europe or South Africa, a result that needs to be investigated to explore the extent to which differences in mortality ascertainment, patient characteristics and comorbidities, or health systems and treatment regimens contribute to variations in outcomes among HIV-positive patients in various settings.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001718.
This study is further discussed in a PLOS Medicine Perspective by Agnes Binagwaho and colleagues
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on universal access to ART, on HIV and AIDS in sub-Saharan Africa, and on HIV and AIDS in South Africa (in English and Spanish)
The World Health Organization provides information on all aspects of HIV/AIDS (in several languages); its 2013 Consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infections: recommendations for a public health approach are available
The 2013 UNAIDS World AIDS Day Report provides up-to-date information about the AIDS epidemic and efforts to halt it
Information about the International Epidemiologic Databases to Evaluate AIDS South African (IeDEA-SA) collaboration and about the ART Cohort Collaboration is available
Personal stories about living with HIV/AIDS are available through Avert, Nam/aidsmap, and Healthtalkonline
doi:10.1371/journal.pmed.1001718
PMCID: PMC4159124  PMID: 25203931
11.  Impact of Antiretroviral Therapy on Tuberculosis Incidence Among HIV-Positive Patients in High-Income Countries 
In 65 121 human immunodeficiency virus–positive individuals from high-income countries, combined antiretroviral therapy (cART) reduced tuberculosis incidence by half. However, increases in tuberculosis incidence shortly after cART, especially in those >50 years old and those with CD4 cell counts <50 cells/μL, suggested unmasking immune reconstitution inflammatory syndrome.
Background. The lower tuberculosis incidence reported in human immunodeficiency virus (HIV)–positive individuals receiving combined antiretroviral therapy (cART) is difficult to interpret causally. Furthermore, the role of unmasking immune reconstitution inflammatory syndrome (IRIS) is unclear. We aim to estimate the effect of cART on tuberculosis incidence in HIV-positive individuals in high-income countries.
Methods. The HIV-CAUSAL Collaboration consisted of 12 cohorts from the United States and Europe of HIV-positive, ART-naive, AIDS-free individuals aged ≥18 years with baseline CD4 cell count and HIV RNA levels followed up from 1996 through 2007. We estimated hazard ratios (HRs) for cART versus no cART, adjusted for time-varying CD4 cell count and HIV RNA level via inverse probability weighting.
Results. Of 65 121 individuals, 712 developed tuberculosis over 28 months of median follow-up (incidence, 3.0 cases per 1000 person-years). The HR for tuberculosis for cART versus no cART was 0.56 (95% confidence interval [CI], 0.44–0.72) overall, 1.04 (95% CI, 0.64–1.68) for individuals aged >50 years, and 1.46 (95% CI, 0.70–3.04) for people with a CD4 cell count of <50 cells/μL. Compared with people who had not started cART, HRs differed by time since cART initiation: 1.36 (95% CI, 0.98–1.89) for initiation <3 months ago and 0.44 (95% CI, 0.34–0.58) for initiation ≥3 months ago. Compared with people who had not initiated cART, HRs <3 months after cART initiation were 0.67 (95% CI, 0.38–1.18), 1.51 (95% CI, 0.98–2.31), and 3.20 (95% CI, 1.34–7.60) for people <35, 35–50, and >50 years old, respectively, and 2.30 (95% CI, 1.03–5.14) for people with a CD4 cell count of <50 cells/μL.
Conclusions. Tuberculosis incidence decreased after cART initiation but not among people >50 years old or with CD4 cell counts of <50 cells/μL. Despite an overall decrease in tuberculosis incidence, the increased rate during 3 months of ART suggests unmasking IRIS.
doi:10.1093/cid/cis203
PMCID: PMC3404691  PMID: 22460971
12.  Impact of Antiretroviral Therapy on Incidence of Pregnancy among HIV-Infected Women in Sub-Saharan Africa: A Cohort Study 
PLoS Medicine  2010;7(2):e1000229.
A multicountry cohort study in sub-Saharan Africa by Landon Myer and colleagues reveals higher pregnancy rates in HIV-infected women on antiretroviral therapy (ART).
Background
With the rapid expansion of antiretroviral therapy (ART) services in sub-Saharan Africa there is growing recognition of the importance of fertility and childbearing among HIV-infected women. However there are few data on whether ART initiation influences pregnancy rates.
Methods and Findings
We analyzed data from the Mother-to-Child Transmission-Plus (MTCT-Plus) Initiative, a multicountry HIV care and treatment program for women, children, and families. From 11 programs in seven African countries, women were enrolled into care regardless of HIV disease stage and followed at regular intervals; ART was initiated according to national guidelines on the basis of immunological and/or clinical criteria. Standardized forms were used to collect sociodemographic and clinical data, including incident pregnancies. Overall 589 incident pregnancies were observed among the 4,531 women included in this analysis (pregnancy incidence, 7.8/100 person-years [PY]). The rate of new pregnancies was significantly higher among women receiving ART (9.0/100 PY) compared to women not on ART (6.5/100 PY) (adjusted hazard ratio, 1.74; 95% confidence interval, 1.19–2.54). Other factors independently associated with increased risk of incident pregnancy included younger age, lower educational attainment, being married or cohabiting, having a male partner enrolled into the program, failure to use nonbarrier contraception, and higher CD4 cell counts.
Conclusions
ART use is associated with significantly higher pregnancy rates among HIV-infected women in sub-Saharan Africa. While the possible behavioral or biomedical mechanisms that may underlie this association require further investigation, these data highlight the importance of pregnancy planning and management as a critical but neglected component of HIV care and treatment services.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Human immunodeficiency virus (HIV) causes Acquired Immunodeficiency Syndrome (AIDS), which is a major global cause of disease and death. More than 33 million people around the world are infected with HIV, with nearly 5,500 dying daily from HIV and AIDS-related complications. HIV/AIDS is especially problematic in sub-Saharan Africa, where it is the leading cause of death. There is no cure for HIV/AIDS, but medicines known as “antiretroviral therapy” (ART) can prolong life and reduce complications in patients infected with HIV. 97% of patients with HIV/AIDS live in low- and middle-income countries. According to the World Health Organization, nearly 10 million of these patients need ART. As patients' access to treatment is often hindered by the high cost and low availability of ART, global health efforts have focused on promoting ART use in resource-limited nations. Such efforts also increase awareness of how HIV is spread (contact with blood or semen, in sexual intercourse, sharing needles, or from mother to child during childbirth). ART reduces, but does not remove, the chance of a mother's passing HIV to her child during birth.
Why Was This Study Done?
By the end of 2007, 3 million HIV-infected patients in poor countries were receiving ART. Many of those treated with ART are young women of child-bearing age. Childbirth is an important means of spreading HIV in sub-Saharan Africa, where 60% of all HIV patients are women. This study questions whether the improved health and life expectancy that results from treatment with ART affects pregnancy rates of HIV-infected patients. The study explores this question in seven African countries, by examining the rates of pregnancy in HIV-infected women before and after they started ART.
What Did the Researchers Do and Find?
The authors looked at the records of 4,531 HIV-infected women enrolled in the Mother-to-Child-Transmission-Plus (MTCT-Plus) Initiative in seven African countries. MTCT -Plus, begun in 2002, is a family-centered treatment program that offers regular checkups, blood tests, counseling, and ART treatment (if appropriate) to women and their families. At each checkup, women's CD4+ cell counts and World Health Organization guidelines were used to determine their eligibility for starting ART. Over a 4-year period, nearly a third of the women starting ART experienced a pregnancy: 244 pregnancies occurred in the “pre-ART” group (women not receiving ART) compared to 345 pregnancies in the “on-ART” group (women receiving ART). The chance of pregnancy increased over time in the on-ART group to almost 80% greater than the pre-ART group, while remaining relatively low and constant in the pre-ART group. The authors noted that, as expected, other factors also increased the chances of pregnancy, including younger age, lower educational status, and use of nonbarrier contraception such as injectable hormones.
What Do These Findings Mean?
This study suggests that starting ART is associated with higher pregnancy rates in sub-Saharan Africa, nearly doubling the chances of a woman becoming pregnant. The reasons for this link are unclear. One possible explanation is behavioral: women receiving ART may feel more motivated to have children as their health and quality of life improve. However, the study did not examine how pregnancy desires and sexual activity of women changed while on ART, and cannot discern why ART is linked to increased pregnancy. By using pregnancy data gathered from patient questionnaires rather than laboratory tests, the study is limited by the possibility of inaccurate patient reporting. Understanding how pregnancy rates vary in HIV-infected women receiving ART helps support the formation of responsive, effective HIV programs. Female HIV patients of child-bearing age, who form the majority of patients receiving ART in sub-Saharan Africa, would benefit from programs that combine starting HIV treatment with ART with education and contraception counseling and pregnancy-related care.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000229.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including a list of articles and other sources of information about the primary care of adolescents with HIV
A UNAIDS 2008 report is available on the global AIDS epidemic
The International Planned Parenthood Foundation provides information on sexual and reproductive health and HIV
The International Center for AIDS Care and Treatment Programs at the Columbia University Mailman School of Public health provides information to assist HIV care and treatment programs in resource-limited settings
doi:10.1371/journal.pmed.1000229
PMCID: PMC2817715  PMID: 20161723
13.  Cost-Effectiveness of Early Versus Standard Antiretroviral Therapy in HIV-Infected Adults in Haiti 
PLoS Medicine  2011;8(9):e1001095.
This cost-effectiveness study comparing early versus standard antiretroviral treatment (ART) for HIV, based on randomized clinical trial data from Haiti, reveals that the new WHO guidelines for early ART initiation can be cost-effective in resource-poor settings.
Background
In a randomized clinical trial of early versus standard antiretroviral therapy (ART) in HIV-infected adults with a CD4 cell count between 200 and 350 cells/mm3 in Haiti, early ART decreased mortality by 75%. We assessed the cost-effectiveness of early versus standard ART in this trial.
Methods and Findings
Trial data included use of ART and other medications, laboratory tests, outpatient visits, radiographic studies, procedures, and hospital services. Medication, laboratory, radiograph, labor, and overhead costs were from the study clinic, and hospital and procedure costs were from local providers. We evaluated cost per year of life saved (YLS), including patient and caregiver costs, with a median of 21 months and maximum of 36 months of follow-up, and with costs and life expectancy discounted at 3% per annum. Between 2005 and 2008, 816 participants were enrolled and followed for a median of 21 months. Mean total costs per patient during the trial were US$1,381 for early ART and US$1,033 for standard ART. After excluding research-related laboratory tests without clinical benefit, costs were US$1,158 (early ART) and US$979 (standard ART). Early ART patients had higher mean costs for ART (US$398 versus US$81) but lower costs for non-ART medications, CD4 cell counts, clinically indicated tests, and radiographs (US$275 versus US$384). The cost-effectiveness ratio after a maximum of 3 years for early versus standard ART was US$3,975/YLS (95% CI US$2,129/YLS–US$9,979/YLS) including research-related tests, and US$2,050/YLS excluding research-related tests (95% CI US$722/YLS–US$5,537/YLS).
Conclusions
Initiating ART in HIV-infected adults with a CD4 cell count between 200 and 350 cells/mm3 in Haiti, consistent with World Health Organization advice, was cost-effective (US$/YLS <3 times gross domestic product per capita) after a maximum of 3 years, after excluding research-related laboratory tests.
Trial registration
ClinicalTrials.gov NCT00120510
Please see later in the article for the Editors' Summary
Editors' Summary
Background
AIDS has killed more than 25 million people since 1981, and about 33 million people (most of them living in low- and middle-income countries) are now infected with HIV, the virus that causes AIDS. HIV destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected people died within 10 years of infection. Then, in 1996, highly active antiretroviral therapy (ART) became available and, for people living in affluent countries HIV/AIDS became a chronic condition. However, ART was extremely expensive and so a diagnosis of HIV infection remained a death sentence for people living in developing countries. In 2003, this situation was declared a global health emergency, and governments, international agencies, and funding bodies began to implement plans to increase ART coverage in developing countries. In 2009, more than a third of people in low- and middle-income countries who needed ART were receiving it, on the basis of guidelines that were in place at that time.
Why Was This Study Done?
Until recently, the World Health Organization (WHO) recommended that all HIV-positive patients with CD4 cell count below 200/mm3 blood or an AIDS-defining illness such as Kaposi's sarcoma should be given ART. Then, in 2009, the CIPRA HT-001 randomized clinical trial, which was undertaken in Haiti, reported that patients who started ART when their CD4 cell count was between 200 and 350 cells/mm3 (“early ART”) had a higher survival rate than patients who started ART according to the WHO guidelines (“standard ART”). As a result, WHO now recommends that ART is started in HIV-infected people when their CD4 cell count falls below 350 cells/mm3. But is this new recommendation cost-effective? Do its benefits outweigh its costs? Policy-makers need to know the cost-effectiveness of interventions so that they can allocate their limited resources wisely. A medical intervention is generally considered cost-effective if it costs less than three times a country's per capita gross domestic product (GDP) per year of life saved (YLS). In this study, the researchers assess the cost-effectiveness of early versus standard ART in the CIPRA HT-001 trial.
What Did the Researchers Do and Find?
The researchers used trial data on the use and costs of ART, other medications, laboratory tests, outpatient visits, radiography, procedures, and hospital services to evaluate the costs associated with early ART and standard ART among the 816 CIPRA HT-001 trial participants. The average total costs per patient after a maximum of 3 years treatment were US$1,381 for early ART and US$1,033 for standard ART. These figures dropped to US$1,158 and US$979, respectively, when the costs of research-related tests without clinical benefit were excluded. Patients who received early ART had higher average costs for ART but lower costs for other aspects of their treatment than patients who received standard ART. The incremental cost-effectiveness ratio after 3 years for early ART compared to standard ART was US$3,975/YLS if the costs of research-related tests were included in the calculation. That is, the cost of saving one year of life by starting ART early instead of when the CD4 cell count dropped below 200/mm3 was nearly US$4,000. Importantly, exclusion of the costs of research-related tests reduced the incremental cost-effectiveness ratio of early ART compared to standard ART to US$2,050/YLS.
What Do These Findings Mean?
Because the Haitian GDP per capita is US$785, these findings suggest that, in Haiti, early ART is a cost-effective intervention over a 3-year period. That is, the incremental cost per year of life saved of early ART compared to standard ART after exclusion of research-related tests is less than three times Haiti's per capita GDP. The researchers note that their incremental cost-effectiveness ratios are likely to be conservative because they did not consider the clinical benefits of early ART that continue beyond 3 years—early ART is associated with lower longer-term mortality than standard ART—or the effect of early ART on disability and quality of life. Cost-effectiveness studies now need to be undertaken at different sites to determine whether these findings are generalizable but, for now, this cost-effectiveness study suggests that the new WHO guidelines for ART initiation can be cost-effective in resource-poor settings, information that should help policy-makers in developing countries allocate their limited resources.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001095.
Information is available from the US National Institute of Allergy and infectious diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on the HIV/AIDS in the Caribbean, and on HIV/AIDS treatment and care (in English and Spanish)
WHO provides information about universal access to AIDS treatment (in English, French and Spanish); its 2010 ART guidelines can be downloaded
More information about the CIPRA HT-001 clinical trial is available
Patient stories about living with HIV/AIDS are available through Avert and through the charity website Healthtalkonline
More information about GHESKIO is available from Weill Cornell Global Health
doi:10.1371/journal.pmed.1001095
PMCID: PMC3176754  PMID: 21949643
14.  Pharmacy Refill Adherence Compared with CD4 Count Changes for Monitoring HIV-Infected Adults on Antiretroviral Therapy 
PLoS Medicine  2008;5(5):e109.
Background
World Health Organization (WHO) guidelines for monitoring HIV-infected individuals taking combination antiretroviral therapy (cART) in resource-limited settings recommend using CD4+ T cell (CD4) count changes to monitor treatment effectiveness. In practice, however, falling CD4 counts are a consequence, rather than a cause, of virologic failure. Adherence lapses precede virologic failure and, unlike CD4 counts, data on adherence are immediately available to all clinics dispensing cART. However, the accuracy of adherence assessments for predicting future or detecting current virologic failure has not been determined. The goal of this study therefore was to determine the accuracy of adherence assessments for predicting and detecting virologic failure and to compare the accuracy of adherence-based monitoring approaches with approaches monitoring CD4 count changes.
Methodology and Findings
We conducted an observational cohort study among 1,982 of 4,984 (40%) HIV-infected adults initiating non-nucleoside reverse transcriptase inhibitor-based cART in the Aid for AIDS Disease Management Program, which serves nine countries in southern Africa. Pharmacy refill adherence was calculated as the number of months of cART claims submitted divided by the number of complete months between cART initiation and the last refill prior to the endpoint of interest, expressed as a percentage. The main outcome measure was virologic failure defined as a viral load > 1,000 copies/ml (1) at an initial assessment either 6 or 12 mo after cART initiation and (2) after a previous undetectable (i.e., < 400 copies/ml) viral load (breakthrough viremia). Adherence levels outperformed CD4 count changes when used to detect current virologic failure in the first year after cART initiation (area under the receiver operating characteristic [ROC] curves [AUC] were 0.79 and 0.68 [difference = 0.11; 95% CI 0.06 to 0.16; χ2 = 20.1] respectively at 6 mo, and 0.85 and 0.75 [difference = 0.10; 95% CI 0.05 to 0.14; χ2 = 20.2] respectively at 12 mo; p < 0.001 for both comparisons). When used to detect current breakthrough viremia, adherence and CD4 counts were equally accurate (AUCs of 0.68 versus 0.67, respectively [difference = 0.01; 95% CI −0.06 to 0.07]; χ2 = 0.1, p > 0.5). In addition, adherence levels assessed 3 mo prior to viral load assessments were as accurate for virologic failure occurring approximately 3 mo later as were CD4 count changes calculated from cART initiation to the actual time of the viral load assessments, indicating the potential utility of adherence assessments for predicting future, rather than simply detecting current, virologic failure. Moreover, combinations of CD4 count and adherence data appeared useful in identifying patients at very low risk of virologic failure.
Conclusions
Pharmacy refill adherence assessments were as accurate as CD4 counts for detecting current virologic failure in this cohort of patients on cART and have the potential to predict virologic failure before it occurs. Approaches to cART scale-up in resource-limited settings should include an adherence-based monitoring approach.
Analyzing pharmacy and laboratory records from 1,982 patients beginning HIV therapy in southern Africa, Gregory Bisson and colleagues find medication adherence superior to CD4 count changes in identifying treatment failure.
Editors' Summary
Background.
Globally, more than 30 million people are infected with the human immunodeficiency virus (HIV), the cause of acquired immunodeficiency syndrome (AIDS). Combinations of antiretroviral drugs that hold HIV in check (viral suppression) have been available since 1996. Unfortunately, most of the people affected by HIV/AIDS live in developing countries and cannot afford these expensive drugs. As a result, life expectancy has plummeted and economic growth has reversed in these poor countries since the beginning of the AIDS pandemic. Faced with this humanitarian crisis, the lack of access to HIV treatment was declared a global health emergency in 2003. Today, through the concerted efforts of governments, international organizations, and funding bodies, about a quarter of the HIV-positive people in developing and transitional countries who are in immediate need of life-saving, combination antiretroviral therapy (cART) receive the drugs they need.
Why Was This Study Done?
To maximize the benefits of cART, health-care workers in developing countries need simple, affordable ways to monitor viral suppression in their patients—a poor virologic response to cART can lead to the selection of drug-resistant HIV, rapid disease progression, and death. In developed countries, virologic response is monitored by measuring the number of viral particles in patients' blood (viral load) but this technically demanding assay is unavailable in most developing countries. Instead, the World Health Organization recommends that CD4+ T cell (CD4) counts be used to monitor patient responses to cART in resource-limited settings. HIV results in loss of CD4 cells (a type of immune system cell), so a drop in a patient's CD4 count often indicates virologic failure (failure of treatment to suppress the virus). However, falling CD4 counts are often a result of virologic failure and therefore monitoring CD4 counts for drops is unlikely to prevent virologic failure from occurring. Rather, falling CD4 counts are often used only to guide a change to new medicines, which may be even more expensive or difficult to take. On the other hand “adherence lapses”—the failure to take cART regularly—often precede virologic failure, so detecting them early provides an opportunity for improvement in adherence that could prevent virologic failure. Because clinics that dispense cART routinely collect data that can be used to calculate adherence, in this study the researchers investigate whether assessing adherence might provide an alternative, low-cost way to monitor and predict virologic failure among HIV-infected adults on cART.
What Did the Researchers Do and Find?
The Aid for AIDS Disease Management Program provides cART to medical insurance fund subscribers in nine countries in southern Africa. Data on claims for antiretroviral drugs made through this program, plus CD4 counts assessed at about 6 or 12 months after initiating cART, and viral load measurements taken within 45 days of a CD4 count, were available for nearly 2,000 HIV-positive adults who had been prescribed a combination of HIV drugs including either efavirenz or nevirapine. The researchers defined adherence as the number of months of cART claims submitted divided by the number of complete months between cART initiation and the last pharmacy refill before a viral load assessment was performed. Virologic failure was defined in two ways: as a viral load of more than 1,000 copies per ml of blood 6 or 12 months after cART initiation, or as a rebound of viral load to similar levels after a previously very low reading (breakthrough viremia). The researchers' statistical analysis of these data shows that at 6 and 12 months after initiation of cART, adherence levels indicated virologic failure more accurately than CD4 count changes. For breakthrough viremia, both measurements were equally accurate. Adherence levels during the first 3 months of cART predicted virologic failure at 6 months as accurately as did CD4 count changes since cART initiation. Finally, the combination of adherence levels and CD4 count changes accurately identified patients at very low risk of virologic failure.
What Do These Findings Mean?
These findings suggest that adherence assessments (based in this study on insurance claims for pharmacy refills) can identify the patients on cART who are at high and low risk of virologic failure at least as accurately as CD4 counts. In addition, they suggest that adherence assessments could be used for early identification of patients at high risk of virologic failure, averting the health impact of treatment failure and the cost of changing to second-line drug regimens. Studies need to be done in other settings (in particular, in public clinics where cART is provided without charge) to confirm the generalizability of these findings. These finding do not change that fact that monitoring CD4 counts plays an important role in deciding when to start cART or indicating when cART is no longer protecting the immune system. But, write the researchers, systematic monitoring of adherence to cART should be considered as an alternative to CD4 count monitoring in patients who are receiving cART in resource-limited settings or as a way to direct the use of viral load testing where feasible.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050109.
This study is discussed further in a PLoS Medicine Perspective by David Bangsberg
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including an article about adherence to antiretroviral therapy
Information is available from Avert, an international AIDS charity, on HIV and AIDS in Africa and on providing AIDS drug treatment for millions
The World Health Organization provides information about universal access to HIV treatment (in several languages) and on its recommendations for antiretroviral therapy for HIV infection in adults and adolescents
The US Centers for Disease Control and Prevention also provides information on global efforts to deal with the HIV/AIDS pandemic (in English and Spanish)
doi:10.1371/journal.pmed.0050109
PMCID: PMC2386831  PMID: 18494555
15.  Simplified HIV Testing and Treatment in China: Analysis of Mortality Rates Before and After a Structural Intervention 
PLoS Medicine  2015;12(9):e1001874.
Background
Multistage stepwise HIV testing and treatment initiation procedures can result in lost opportunities to provide timely antiretroviral therapy (ART). Incomplete patient engagement along the continuum of HIV care translates into high levels of preventable mortality. We aimed to evaluate the ability of a simplified test and treat structural intervention to reduce mortality.
Methods and Findings
In the “pre-intervention 2010” (from January 2010 to December 2010) and “pre-intervention 2011” (from January 2011 to December 2011) phases, patients who screened HIV-positive at health care facilities in Zhongshan and Pubei counties in Guangxi, China, followed the standard-of-care process. In the “post-intervention 2012” (from July 2012 to June 2013) and “post-intervention 2013” (from July 2013 to June 2014) phases, patients who screened HIV-positive at the same facilities were offered a simplified test and treat intervention, i.e., concurrent HIV confirmatory and CD4 testing and immediate initiation of ART, irrespective of CD4 count. Participants were followed for 6–18 mo until the end of their study phase period. Mortality rates in the pre-intervention and post-intervention phases were compared for all HIV cases and for treatment-eligible HIV cases. A total of 1,034 HIV-positive participants (281 and 339 in the two pre-intervention phases respectively, and 215 and 199 in the two post-intervention phases respectively) were enrolled. Following the structural intervention, receipt of baseline CD4 testing within 30 d of HIV confirmation increased from 67%/61% (pre-intervention 2010/pre-intervention 2011) to 98%/97% (post-intervention 2012/post-intervention 2013) (all p < 0.001 [i.e., for all comparisons between a pre- and post-intervention phase]), and the time from HIV confirmation to ART initiation decreased from 53 d (interquartile range [IQR] 27–141)/43 d (IQR 15–113) to 5 d (IQR 2–12)/5 d (IQR 2–13) (all p < 0.001). Initiation of ART increased from 27%/49% to 91%/89% among all cases (all p < 0.001) and from 39%/62% to 94%/90% among individuals with CD4 count ≤ 350 cells/mm3 or AIDS (all p < 0.001). Mortality decreased from 27%/27% to 10%/10% for all cases (all p < 0.001) and from 40%/35% to 13%/13% for cases with CD4 count ≤ 350 cells/mm3 or AIDS (all p < 0.001). The simplified test and treat intervention was significantly associated with decreased mortality rates compared to pre-intervention 2011 (adjusted hazard ratio [aHR] 0.385 [95% CI 0.239–0.620] and 0.380 [95% CI 0.233–0.618] for the two post-intervention phases, respectively, for all newly diagnosed HIV cases [both p < 0.001], and aHR 0.369 [95% CI 0.226–0.603] and 0.361 [95% CI 0.221–0.590] for newly diagnosed treatment-eligible HIV cases [both p < 0.001]). The unit cost of an additional patient receiving ART attributable to the intervention was US$83.80. The unit cost of a death prevented because of the intervention was US$234.52.
Conclusions
Our results demonstrate that the simplified HIV test and treat intervention promoted successful engagement in care and was associated with a 62% reduction in mortality. Our findings support the implementation of integrated HIV testing and immediate access to ART irrespective of CD4 count, in order to optimize the impact of ART.
In a before and after analysis, Zunyou Wu and colleagues assess the impact on mortality of an HIV test and treat intervention in two counties in Guangxi, China.
Editors' Summary
Background
Every year, about 2.1 million people (mostly living in resource-limited countries) are newly infected with HIV, the virus that causes AIDS and that has killed 39 million people over the past three decades. HIV, which is usually transmitted through unprotected sex with an infected individual, gradually destroys CD4 lymphocytes and other immune system cells, leaving HIV-positive individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-positive individuals died within ten years of infection. Then, in 1996, effective antiretroviral therapy (ART) became available, and, for people living in high-income countries, HIV became a chronic condition. But ART was expensive, so HIV/AIDS remained largely untreated and fatal in resource-limited countries. In 2003, the international community began to work towards achieving universal ART coverage. By 2013, about 12.9 million people living with HIV (a third of all HIV-positive people) had access to ART, and the rate of AIDS-related deaths had fallen by a third from its 2005 peak.
Why Was This Study Done?
Unfortunately, in many countries, late diagnosis of HIV infection, incomplete linkage to care after diagnosis, and high rates of loss to follow-up before and after ART initiation remain major barriers to effective HIV/AIDS treatment and to maximization of the preventative benefits of ART: as well as keeping HIV-positive people healthy, ART also reduces their chances of transmitting HIV to a sexual partner. Here, the researchers investigate whether a simplified “test and treat” intervention can reduce HIV/AIDS mortality (death) rates in China by reducing these barriers. Currently, CD4 testing is offered to people in China only after an initial HIV diagnosis has been confirmed using a second type of test. This standard-of-care policy introduces a delay into ART initiation because a CD4 count below 350 cells/μl blood is the primary determinant of eligibility for treatment through the Chinese national free ART program. By contrast, the simplified test and treat intervention, which is designed to be completed within a week of the patient’s first positive HIV test result, incorporates immediate HIV confirmatory testing, pre-ART CD4 testing, pre-treatment counseling, and ART initiation regardless of CD4 count.
What Did the Researchers Do and Find?
The researchers followed about 1,000 patients who tested positive for HIV at health care facilities in two counties in Guangxi (one of the Chinese provinces most heavily affected by HIV/AIDS) in two 12-month pre-intervention phases, during which patients followed the standard-of-care process, and two 12-month post-intervention phases, during which patients were offered the simplified test and treat intervention. About 65% and 97% of the patients received baseline CD4 testing during the pre-intervention and post-intervention phases, respectively. Following the structural intervention, the time from HIV confirmation to ART initiation decreased from around 50 days to five days, and the proportion of individuals who initiated ART increased from below 36% to above 90% among all the patients and from below 47% to above 93% among patients eligible for treatment under the standard-of-care policy. Notably, the mortality rate decreased from about 26% to about 10% among all the study participants following the intervention, and from about 37% to about 13% among the participants eligible for ART under the standard-of-care policy. Finally, the researchers estimated that the cost of each death prevented by the intervention was about US$234.52 over the study period; importantly, most of this cost was accrued during the initial year of the intervention.
What Do These Findings Mean?
These findings indicate that, in the two Chinese counties involved in this study, the simplified test and treat intervention—which incorporated a streamlined, standardized time frame for HIV diagnosis and expanded access to ART—promoted successful engagement in care among HIV-positive individuals and was associated with a 62% reduction in mortality. Moreover, the intervention required very little further investment once it had been set up and should, therefore, be sustainable. Because the design of the simplified test and treat intervention took into account the characteristics of the HIV epidemic and the health care structure in China, these findings may not be fully generalizable to other countries. In addition, reliance on a pre-intervention/post-intervention study design, rather than a controlled trial, may limit the accuracy of these findings. Nevertheless, these results suggest that the implementation of integrated HIV testing and immediate access to ART regardless of CD4 count has the potential to optimize the individual and public health impacts of ART by ensuring that fewer patients are lost along the multistage continuum of HIV testing and treatment.
Additional Information
This list of resources contains links that can be accessed when viewing the PDF on a device or via the online version of the article at http://dx.doi.org/10.1371/journal.pmed.1001874.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, summaries of recent research findings on HIV care and treatment, and personal stories about living with HIV/AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on universal access to ART and on HIV/AIDS in China; Avert also provides personal stories about living with HIV/AIDS
The World Health Organization provides information on all aspects of HIV/AIDS (in several languages), including its Consolidated Guidelines on the Use of Antiretroviral Therapy for Treating and Preventing HIV Infection, its recently released consolidated guidelines on HIV testing, and information on the WHO/UNAIDS Treatment 2.0 strategy, an initiative to expand access to HIV testing and ART
The UNAIDS Fast-Track Strategy to End the AIDS Epidemic by 2030 provides up-to-date information about the AIDS epidemic and efforts to halt it, including progress towards universal access to antiretroviral therapy
doi:10.1371/journal.pmed.1001874
PMCID: PMC4562716  PMID: 26348214
16.  Immunological profiling of tuberculosis-associated immune reconstitution inflammatory syndrome and non-immune reconstitution inflammatory syndrome death in HIV-infected adults with pulmonary tuberculosis starting antiretroviral therapy: a prospective observational cohort study 
The Lancet. Infectious diseases  2015;15(4):429-438.
Summary
Background
Patients co-infected with advanced HIV and tuberculosis are at risk of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) and death soon after initiation of antiretroviral therapy (ART). Tuberculosis-associated IRIS has been associated with quicker recovery of cellular immune responses after ART initiation and early mortality with slower recovery of these responses. We aimed to assess whether patients who have these outcomes have distinct immunological profiles before and after ART initiation.
Methods
We undertook this prospective cohort study at 22 public clinics and the main public hospital in Gaborone, Botswana, in ART-naive adults (aged ≥21 years) with advanced HIV (CD4 cell counts ≤125 cells per μL) and pulmonary tuberculosis. We obtained data for clinical variables and for levels of 29 plasma biomarkers, quantified by Luminex assay. We classified patients as having tuberculosis-associated IRIS, early mortality, or survival without a diagnosis of tuberculosis-associated IRIS (controls), on the basis of outcomes recorded in the 6 months after ART initiation. We used rank-sum or χ² tests, and logistic regression with odds ratios (OR) and 95% CIs, to assess the association between variables measured before and 4 weeks after ART initiation with death and tuberculosis-associated IRIS, compared with controls.
Findings
Between Nov 12, 2009, and July 3, 2013, we enrolled 201 participants. 31 (15%) patients left the study before ART initiation, leaving 170 (85%) patients for analysis. Patients with tuberculosis-associated IRIS had reduced pre-ART concentrations of several pro-inflammatory biomarkers, including interleukin (IL)-6 (adjusted OR per 1 log10 increase 0·40 [95% CI 0·18–0·89]). However, patients with early death had increased pre-ART concentrations of inflammatory biomarkers, including monocyte chemoattractant protein-1 (adjusted OR 9·0 [95% CI 1·0–80·0]) and tumour necrosis factor (TNF)-α (7·8 [1·1–55·2]). At week 4 after ART initiation, tuberculosis-associated IRIS was independently associated with greater increases in several inflammatory biomarkers, including IL-6 (adjusted OR 1·7 [95% CI 1·2–2·5]) and TNF-α (1·5 [1·0–2·2]), versus controls. Death was likewise associated with greater increases in systemic inflammatory markers, including granulocyte colony-stimulating factor (adjusted OR 2·8 [95% CI 1·3–6·1]), IL-12p40 (1·8 [1·0–3·4]), and IL-15 (2·0 [1·1–3·7]), versus controls. However, changes in CD4 cell count during ART, which were similar between controls and patients with tuberculosis-associated IRIS (p=0·45), were substantially lower in patients who died (p=0·006).
Interpretation
Distinct immunologic profiles pre- and post-ART initiation characterize advanced HIV/TB patients who experience TB-IRIS and death. Interventions that decrease inflammation while promoting cellular immune recovery on ART among HIV/TB co-infected patients should be considered.
Funding
National Institutes of Health and the Penn Center for AIDS Research.
doi:10.1016/S1473-3099(15)70008-3
PMCID: PMC4624391  PMID: 25672566
17.  Effectiveness of Early Antiretroviral Therapy Initiation to Improve Survival among HIV-Infected Adults with Tuberculosis: A Retrospective Cohort Study 
PLoS Medicine  2011;8(5):e1001029.
Molly Franke, Megan Murray, and colleagues report that early cART reduces mortality among HIV-infected adults with tuberculosis and improves retention in care, regardless of CD4 count.
Background
Randomized clinical trials examining the optimal time to initiate combination antiretroviral therapy (cART) in HIV-infected adults with sputum smear-positive tuberculosis (TB) disease have demonstrated improved survival among those who initiate cART earlier during TB treatment. Since these trials incorporated rigorous diagnostic criteria, it is unclear whether these results are generalizable to the vast majority of HIV-infected patients with TB, for whom standard diagnostic tools are unavailable. We aimed to examine whether early cART initiation improved survival among HIV-infected adults who were diagnosed with TB in a clinical setting.
Methods and Findings
We retrospectively reviewed charts for 308 HIV-infected adults in Rwanda with a CD4 count≤350 cells/µl and a TB diagnosis. We estimated the effect of cART on survival using marginal structural models and simulated 2-y survival curves for the cohort under different cART strategies:start cART 15, 30, 60, or 180 d after TB treatment or never start cART. We conducted secondary analyses with composite endpoints of (1) death, default, or lost to follow-up and (2) death, hospitalization, or serious opportunistic infection. Early cART initiation led to a survival benefit that was most marked for individuals with low CD4 counts. For individuals with CD4 counts of 50 or 100 cells/µl, cART initiation at day 15 yielded 2-y survival probabilities of 0.82 (95% confidence interval: [0.76, 0.89]) and 0.86 (95% confidence interval: [0.80, 0.92]), respectively. These were significantly higher than the probabilities computed under later start times. Results were similar for the endpoint of death, hospitalization, or serious opportunistic infection. cART initiation at day 15 versus later times was protective against death, default, or loss to follow-up, regardless of CD4 count. As with any observational study, the validity of these findings assumes that biases from residual confounding by unmeasured factors and from model misspecification are small.
Conclusions
Early cART reduced mortality among individuals with low CD4 counts and improved retention in care, regardless of CD4 count.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
HIV infection has exacerbated the global tuberculosis (TB) epidemic, especially in sub-Saharan Africa, in which in some countries, 70% of people with TB are currently also HIV positive—a condition commonly described as HIV/TB co-infection. The management of patients with HIV/TB co-infection is a major public health concern.
There is relatively little good evidence on the best time to initiate combination antiretroviral therapy (cART) in adults with HIV/TB co-infection. Clinicians sometimes defer cART in individuals initiating TB treatment because of concerns about complications (such as immune reconstitution inflammatory syndrome) and the risk of reduced adherence if patients have to remember to take two sets of pills. However, starting cART later in those patients who are infected with both HIV and TB can result in potentially avoidable deaths during therapy.
Why Was This Study Done?
Several randomized control trials (RCTs) have been carried out, and the results of three of these studies suggest that, among individuals with severe immune suppression, early initiation of cART (two to four weeks after the start of TB treatment) leads to better survival than later ART initiation (two to three months after the start of TB treatment). These results were reported in abstract form, but the full papers have not yet been published. One problem with RCTs is that they are carried out under controlled conditions that might not represent well the conditions in varied settings around the world. Therefore, observational studies that examine how effective a treatment is in routine clinical conditions can provide information that complements that obtained during clinical trials. In this study, the researchers aimed to confirm the results from RCTs among a cohort of adult patients with HIV/TB co-infection in Rwanda, diagnosed under routine program conditions and using routinely collected clinical data. The researchers also wanted to investigate whether early cART initiation reduced the risk of other adverse outcomes, including treatment default and loss to follow-up.
What Did the Researchers Do and Find?
The researchers retrospectively reviewed the charts and other program records of 308 patients with HIV, who had CD4 counts≤350 cells/µl, were aged 15 years or more, had never previously taken cART, and received their first TB treatment at one of five cART sites (two urban, three rural) in Rwanda between January 2004 and February 2007. Using this method, the researchers collected baseline demographic and clinical variables and relevant clinical follow-up data. They then used this data to estimate the effect of cART on survival by using sophisticated statistical models that calculated the effects of initiating cART at 15, 30, 60, or 180 d after the start of TB treatment or not at all.
The researchers then conducted a further analysis to assess combined outcomes of (1) death, default, lost to follow-up, and (2) death, hospitalization due to any cause, or occurrence of severe opportunistic infections, such as Kaposi's sarcoma. The researchers used the resulting multivariable model to estimate survival probabilities for each individual, based on his/her baseline characteristics.
The researchers found that when they set their model to first CD4 cell counts of 50 and 100 cells/µl, and starting cART at day 15, mean survival probabilities at two years were 0.82 and 0.86, respectively, statistically significantly higher than the survival probabilities calculated for each of the other treatment strategies, where cART was started later. They observed a similar pattern for the combined outcome of death, hospitalization, or serious opportunistic infection In addition, two-year outcomes for death or lost to follow-up were also improved with early cART, regardless of CD4 count at treatment initiation.
What Do These Findings Mean?
These findings show that in a real world program setting, starting cART 15 d after the start of TB treatment is more beneficial (measured by differences in survival probabilities) among patients with HIV/TB co-infection who have CD4 cell counts≤100 cells/µl than starting later. Early cART initiation may also increase retention in care for all individuals with CD4 cell counts≤350 cells/µl.
As the outcomes of this modeling study are based on data from a retrospective observational study, the biases associated with use of these data must be carefully addressed. However, the results support the recommendation of cART initiation after 15 d of TB treatment for patients with CD4 cell counts≤100 cells/µl and can be used as an advocacy base for TB treatment to be used as an opportunity to refer and retain HIV-infected individuals in care, regardless of CD4 cell count.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001029.
Information is available on HIV/TB co-infection from the World Health Organization, the US Centers for Disease Control and Prevention, and the International AIDS Society
doi:10.1371/journal.pmed.1001029
PMCID: PMC3086874  PMID: 21559327
18.  Scaling Up the 2010 World Health Organization HIV Treatment Guidelines in Resource-Limited Settings: A Model-Based Analysis 
PLoS Medicine  2010;7(12):e1000382.
Rochelle Walensky and colleagues use a model-based analysis to examine which of the 2010 WHO antiretroviral therapy guidelines should be implemented first in resource-limited settings by ranking them according to survival, cost-effectiveness, and equity.
Background
The new 2010 World Health Organization (WHO) HIV treatment guidelines recommend earlier antiretroviral therapy (ART) initiation (CD4<350 cells/µl instead of CD4<200 cells/µl), multiple sequential ART regimens, and replacement of first-line stavudine with tenofovir. This paper considers what to do first in resource-limited settings where immediate implementation of all of the WHO recommendations is not feasible.
Methods and Findings
We use a mathematical model and local input data to project clinical and economic outcomes in a South African HIV-infected cohort (mean age = 32.8 y, mean CD4 = 375/µl). For the reference strategy, we assume that all patients initiate stavudine-based ART with WHO stage III/IV disease and receive one line of ART (stavudine/WHO/one-line). We rank—in survival, cost-effectiveness, and equity terms—all 12 possible combinations of the following: (1) stavudine replacement with tenofovir, (2) ART initiation (by WHO stage, CD4<200 cells/µl, or CD4<350 cells/µl), and (3) one or two regimens, or lines, of available ART. Projected life expectancy for the reference strategy is 99.0 mo. Considering each of the guideline components separately, 5-y survival is maximized with ART initiation at CD4<350 cells/µl (stavudine/<350/µl/one-line, 87% survival) compared with stavudine/WHO/two-lines (66%) and tenofovir/WHO/one-line (66%). The greatest life expectancies are achieved via the following stepwise programmatic additions: stavudine/<350/µl/one-line (124.3 mo), stavudine/<350/µl/two-lines (177.6 mo), and tenofovir/<350/µl/two-lines (193.6 mo). Three program combinations are economically efficient: stavudine/<350/µl/one-line (cost-effectiveness ratio, US$610/years of life saved [YLS]), tenofovir/<350/µl/one-line (US$1,140/YLS), and tenofovir/<350/µl/two-lines (US$2,370/YLS).
Conclusions
In settings where immediate implementation of all of the new WHO treatment guidelines is not feasible, ART initiation at CD4<350 cells/µl provides the greatest short- and long-term survival advantage and is highly cost-effective.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Since 1981, acquired immunodeficiency syndrome (AIDS) has killed more than 25 million people, and about 33 million people (30 million of them in low- and middle-income countries) are now infected with the human immunodeficiency virus (HIV), which causes AIDS. HIV destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other infections (so-called opportunistic infections). Early in the AIDS epidemic, most people with HIV died within 10 years of infection. Then, in 1996, highly active antiretroviral therapy (ART)—a combination of several powerful antiretroviral drugs—was developed. Now, in resource-rich countries, clinicians care for people with HIV by prescribing ART regimens tailored to each individual's needs. They also regularly measure the amount of virus in their patients' blood, test for antiretroviral-resistant viruses, and monitor the health of their patients' immune systems through regular CD4 cell counts. As a result, the life expectancy of patients with HIV in developed countries has dramatically improved.
Why Was This Study Done?
Initially, resource-limited countries could not afford to provide ART for their populations, and the life expectancy of HIV-positive people remained low. Now, through the concerted efforts of governments, the World Health Organization (WHO), and other international agencies, more than a third of the people in low- and middle-income countries who need ART are receiving it. However, many without access are still in need of ART, and ART programs in developing countries follow a public-health approach rather than an individualized approach. That is, drug regimens, clinical decision-making, and disease monitoring are all standardized and follow recommendations in the 2006 WHO ART guidelines. This year (2010), these guidelines were revised. The guidelines now recommend the following: earlier ART initiation—when the CD4 count falls below 350/µl of blood, instead of below 200/µl as in the 2006 guidelines; the provision of sequential ART regimens instead of a single regimen; and the replacement of the antiretroviral drug stavudine with tenofovir, a less toxic but more expensive drug, in first-line ART regimens. However, many resource-limited countries are still struggling to implement the 2006 guidelines, so which of these new recommendations should be prioritized? Here, the researchers use a mathematical model to address this question.
What Did the Researchers Do and Find?
The Cost Effectiveness of AIDS Complications (CEPAC)–International model simulates the natural history and treatment of HIV disease. The researchers entered South African clinical and cost data for HIV treatment into this model and then used it to project survival and costs in a hypothetical group of South African HIV-positive patients under alternative guideline prioritization scenarios. The reference strategy for the simulations (denoted as “stavudine/WHO/one-line”) assumed that patients (with a mean CD4 count of 375/µl) began a single stavudine-based ART regimen when they developed WHO stage III/IV HIV disease (i.e., when patients develop multiple opportunistic infections such as tuberculosis and pneumonia). When the new guideline recommendations were considered separately, ART initiation at CD4<350/µl (stavudine/<350/µl/one-line) maximized five-year survival. Stepwise adjustment from the reference strategy (which had a life expectancy 99.0 months) through strategies of stavudine/<350/µl/one-line (a projected life expectancy of 124.3 months), stavudine/<350/µl/two-lines (177.6 months), and tenofovir/<350/µl/two-lines (193.6 months) produced the greatest improvements in life expectancy. Finally, strategies of stavudine/<350/µl/one-line, tenofovir/<350/µl/one-line, and tenofovir/<350µl/two-lines produced incremental cost-effectiveness ratios of US$610, US$1,140, and US$2,370 per year of life saved, respectively.
What Do These Findings Mean?
As with all mathematical models, the accuracy of these findings are dependent on the assumptions included in the model and on the data populating it. Nevertheless, these findings suggest that, where resources are limited and immediate implementation of all the new WHO recommendations is impossible, ART initiation at a CD4 count of less than 350/µl would provide the greatest survival advantage and would be very cost-effective. In countries that are already initiating ART at this threshold and that have access to CD4 monitoring, a switch from stavudine to tenofovir would further increase survival and would also be cost-effective. Finally, although access to second-line ART regimen would provide more clinical benefits than access to tenofovir, the cost of this change in strategy would be substantially greater. Importantly, these findings should help to avoid the complete dismissal of the revised WHO guidelines on the basis of cost and should help policy makers adjust their ART program strategies to maximize their clinical benefits and cost effectiveness.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000382.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV/AIDS in South Africa and on HIV/AIDS treatment and care (in English and Spanish)
WHO provides information about universal access to AIDS treatment (in English, French, and Spanish); its 2010 ART guidelines can be downloaded
More information on the CEPAC model is available
doi:10.1371/journal.pmed.1000382
PMCID: PMC3014084  PMID: 21209794
19.  Clinical Features and Serum Biomarkers in HIV Immune Reconstitution Inflammatory Syndrome after Cryptococcal Meningitis: A Prospective Cohort Study 
PLoS Medicine  2010;7(12):e1000384.
David Boulware and colleagues investigate clinical features in a prospective cohort with AIDS and recent cryptococcal meningitis after initiation of antiretroviral therapy to identify biomarkers for prediction and diagnosis of CM-IRIS (cryptococcal meninigitis-related immune reconstitution inflammatory syndrome).
Background
Although antiretroviral therapy (ART) improves survival in persons with cryptococcal meningitis (CM) and AIDS, ART frequently elicits HIV immune reconstitution inflammatory syndrome (IRIS), an exaggerated and frequently deadly inflammatory reaction that complicates recovery from immunodeficiency. The pathogenesis of IRIS is poorly understood and prediction of IRIS is not possible.
Methods and Findings
We prospectively followed 101 ART-naïve Ugandans with AIDS and recent CM for one year after initiating ART, and used Luminex multiplex assays to compare serum cytokine levels in participants who did or did not develop IRIS. IRIS occurred in 45% of participants with recent CM on ART, including 30% with central nervous system (CNS) manifestations. The median time to CM-IRIS was 8.8 wk on ART. Overall mortality on ART was 36% with IRIS and 21% without IRIS. CM-IRIS was independently associated with death (HR = 2.3, 95% CI 1.1–5.1, p = 0.04). Patients experiencing subsequent CM-IRIS had 4-fold higher median serum cryptococcal antigen (CRAG) levels pre-ART (p = 0.006). Higher pre-ART levels of interleukin (IL)-4 and IL-17 as well as lower tumor necrosis factor (TNF)-α, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and vascular endothelial growth factor (VEGF) predicted future IRIS in multivariate analyses (area under the curve [AUC] = 0.82). An algorithm based on seven pre-ART serum biomarkers was a robust tool for stratifying high (83%), moderate (48%), and low risk (23%) for IRIS in the cohort. After ART was initiated, increasing levels of C-reactive protein (CRP), D-dimer, IL-6, IL-7, IL-13, G-CSF, or IL-1RA were associated with increasing hazard of IRIS by time-to-event analysis (each p≤0.001). At the time of IRIS onset, multiple proinflammatory cytokine responses were present, including CRP and IL-6. Mortality was predicted by pre-ART increasing IL-17, decreasing GM-CSF, and CRP level >32 mg/l (highest quartile). Pre-ART CRP level >32 mg/l alone was associated with future death (OR = 8.3, 95% CI 2.7–25.6, p<0.001).
Conclusions
Pre-ART increases in Th17 and Th2 responses (e.g., IL-17, IL-4) and lack of proinflammatory cytokine responses (e.g., TNF-α, G-CSF, GM-CSF, VEGF) predispose individuals to subsequent IRIS, perhaps as biomarkers of immune dysfunction and poor initial clearance of CRAG. Although requiring validation, these biomarkers might be an objective tool to stratify the risk of CM-IRIS and death, and could be used clinically to guide when to start ART or use prophylactic interventions.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Since 1981, AIDS has killed more than 25 million people and about 33 million people are now infected with HIV, which causes AIDS. HIV, which is most often transmitted through unprotected sex with an HIV-infected partner, infects and kills immune system cells. Eventually, the immune system becomes so weak that unusual infections begin to occur. These “opportunistic” infections are infections that take advantage of the opportunity offered by a weakened immune system. One common and deadly opportunistic infection in people affected by AIDS is cryptococcal meningitis (CM), an infection around the brain that is caused by the fungus Cryptococcus neoformans. About one million cases of CM occur every year. CM can be treated with a drug called amphotericin but usually recurs unless another drug called fluconazole is taken daily thereafter. HIV therapy is lifesaving by suppressing the HIV virus and allowing immune system recovery. This immune recovery also helps to prevent the recurrence of CM.
Why Was This Study Done?
Unfortunately, HIV therapy can also elicit a serious condition called immune reconstitution inflammatory syndrome (IRIS) in people with CM and AIDS. IRIS is an exaggerated inflammatory immune response that kills up to one-third of affected people. Inflammation, which is characterized by swelling and redness, is the body's first defense against infection, but uncontrolled inflammation causes widespread tissue damage. Experts think that CM-IRIS may be the result of an unbalanced recovery of the immune system leading to an inappropriate immune response to persisting C. neoformans fragments and proteins that are slowly cleared from the body over months. Unfortunately, it is impossible to predict which individuals with CM and AIDS will develop IRIS when they are given HIV therapy. In this prospective study, the researchers investigated clinical features and cytokine profiles in a group of Ugandans with AIDS and recent CM for one year after starting HIV therapy to identify biomarkers that could be used to predict and diagnose CM-IRIS. Cytokines are proteins secreted by immune system cells that regulate the immune response; biomarkers are proteins found in the blood that indicate specific diseases.
What Did the Researchers Do and Find?
The researchers enrolled 101 Ugandans with AIDS and recent CM who had not previously received HIV therapy. They compared cytokine patterns in individuals who did and did not subsequently develop IRIS after starting HIV therapy. Overall, 45% of the patients developed IRIS. Deaths occurred in 36% of the patients who developed IRIS and in 21% of those who did not develop IRIS. Patients who developed CM-IRIS after starting HIV therapy had 4-fold higher baseline concentrations of cryptococcal antigen in their blood than patients who did not develop CM-IRIS. Prior to starting HIV therapy, higher levels of the cytokines IL-4 and IL-17 and lower levels of four cytokines—TNF-α, G-CSF, GM-CSF, and VEGF—predicted IRIS development, and an algorithm (formula) based on the baseline levels of seven serum biomarkers was able to group the patients into high, moderate, and low risk of IRIS. After starting HIV therapy, increasing levels of the inflammatory proteins C-reactive protein and D-dimer, and of several cytokines, were associated with an increased risk of IRIS. At the time of IRIS onset, the levels of many proinflammatory cytokine increased. Biomarkers also predicted death after starting HIV therapy with increasing levels of IL-17, decreasing levels of GM-CSF, and a C-reactive protein level of more than 32 mg/l (four times higher than normal) predicted death within one year.
What Do These Findings Mean?
These findings support the hypothesis that some AIDS patients who have a very damaged immune system have a very poor initial immune response and poor clearance of cryptococcus, which predisposes them to IRIS. The findings also identify three distinct phases of IRIS development. Before HIV therapy, a very damaged immune system with a lack of inflammatory responses to infection or inappropriate responses leads to ineffective clearance of the organism and its antigens. After HIV therapy is started, the presence of copious antigens promotes proinflammatory signaling to the immune system. As the immune system recovers proinflammatory immune cells are promoted. Finally, at the time of IRIS, a generalized “cytokine storm” occurs, which is potentially fatal when this inflammation occurs in the brain. The biomarkers identified here as indicators of a predisposition to IRIS need to be validated in more patients in more countries before they can be used as a clinical tool for predicting the risk of IRIS. If they are validated, they could help clinicians decide when to start HIV therapy in patients with AIDS and recent CM, and could guide the use of therapies that could help prevent the abnormal inflammatory responses.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000384.
The US National Institute of Allergy and Infectious Diseases provides information on HIV infection and AIDS
HIV InSite has information on all aspects of HIV/AIDS, including Knowledge Base Chapters on cryptococcosis and HIV and on the clinical implications of IRIS
Information is available from Avert, an international AIDS charity on all aspects of HIV/AIDS, including HIV-related opportunistic infections (in English and Spanish)
The MedlinePlus encyclopedia has a page on cryptococcal meningitis (in English and Spanish)
AIDS InfoNet provides fact sheets on many HIV/AIDS topics, including a fact sheet on cryptococcal meningitis (in several languages) and treatment guidelines for opportunistic infections
doi:10.1371/journal.pmed.1000384
PMCID: PMC3014618  PMID: 21253011
20.  Pretreatment CD4 Cell Slope and Progression to AIDS or Death in HIV-Infected Patients Initiating Antiretroviral Therapy—The CASCADE Collaboration: A Collaboration of 23 Cohort Studies 
PLoS Medicine  2010;7(2):e1000239.
Analyzing data from several thousand cohort study participants, Marcel Wolbers and colleagues find that the rate of CD4 T cell decline is not useful in deciding when to start HIV treatment.
Background
CD4 cell count is a strong predictor of the subsequent risk of AIDS or death in HIV-infected patients initiating combination antiretroviral therapy (cART). It is not known whether the rate of CD4 cell decline prior to therapy is related to prognosis and should, therefore, influence the decision on when to initiate cART.
Methods and Findings
We carried out survival analyses of patients from the 23 cohorts of the CASCADE (Concerted Action on SeroConversion to AIDS and Death in Europe) collaboration with a known date of HIV seroconversion and with at least two CD4 measurements prior to initiating cART. For each patient, a pre-cART CD4 slope was estimated using a linear mixed effects model. Our primary outcome was time from initiating cART to a first new AIDS event or death. We included 2,820 treatment-naïve patients initiating cART with a median (interquartile range) pre-cART CD4 cell decline of 61 (46–81) cells/µl per year; 255 patients subsequently experienced a new AIDS event or death and 125 patients died. In an analysis adjusted for established risk factors, the hazard ratio for AIDS or death was 1.01 (95% confidence interval 0.97–1.04) for each 10 cells/µl per year reduction in pre-cART CD4 cell decline. There was also no association between pre-cART CD4 cell slope and survival. Alternative estimates of CD4 cell slope gave similar results. In 1,731 AIDS-free patients with >350 CD4 cells/µl from the pre-cART era, the rate of CD4 cell decline was also not significantly associated with progression to AIDS or death (hazard ratio 0.99, 95% confidence interval 0.94–1.03, for each 10 cells/µl per year reduction in CD4 cell decline).
Conclusions
The CD4 cell slope does not improve the prediction of clinical outcome in patients with a CD4 cell count above 350 cells/µl. Knowledge of the current CD4 cell count is sufficient when deciding whether to initiate cART in asymptomatic patients.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
More than 30 million people are currently infected with the human immunodeficiency virus (HIV), the cause of acquired immunodeficiency syndrome (AIDS). Most people who become infected with HIV do not become ill immediately although some develop a short flu-like illness shortly after infection. This illness is called “seroconversion” illness because it coincides with the appearance of antibodies to HIV in the blood. The next stage of HIV infection has no major symptoms and may last up to 10 years. During this time, HIV slowly destroys immune system cells (including CD4 cells, a type of lymphocyte). Without treatment, the immune system loses the ability to fight off infections by other disease-causing organisms and HIV-positive people then develop so-called opportunistic infections, Kaposi sarcoma (a skin cancer), or non-Hodgkin lymphoma (a cancer of the lymph nodes) that determine the diagnosis of AIDS. Although HIV-positive people used to die within 10 years of infection on average, the development in 1996 of combination antiretroviral therapy (cART; cocktails of powerful antiretroviral drugs) means that, at least for people living in developed countries, HIV/AIDS is now a chronic, treatable condition.
Why Was This Study Done?
The number of CD4 cells in the blood is a strong predictor of the likelihood of AIDS or death in untreated HIV-positive individuals and in people starting cART. Current guidelines recommend, therefore, that cART is started in HIV-positive patients without symptoms when their CD4 cell count drops below a specified cutoff level (typically 350 cells/µl.) In addition, several guidelines suggest that clinicians should also consider cART in symptom-free HIV-positive patients with a CD4 cell count above the cutoff level if their CD4 cell count has rapidly declined. However, it is not actually known whether the rate of CD4 cell decline (so-called “CD4 slope”) before initiating cART is related to a patient's outcome, so should clinicians consider this measurement when deciding whether to initiate cART? In this study, the researchers use data from CASCADE (Concerted Action on SeroConversion to AIDS and Death in Europe), a large collaborative study of 23 groups of HIV-positive individuals whose approximate date of HIV infection is known, to answer this question.
What Did the Researchers Do and Find?
The researchers undertook survival analyses of patients in the CASCADE collaboration for whom at least two CD4 cell counts had been recorded before starting cART. They calculated a pre-cART CD4 cell count slope from these counts and used statistical methods to investigate whether there was an association between the rate of decline in CD4 cell count and the time from initiating cART to the primary outcome—a first new AIDS-defining event or death. 2820 HIV-positive patients initiating cART were included in the study; the average pre-cART CD4 cell decline among them was 61 cells/µl/year. 255 of the patients experienced a new AIDS-related event or died after starting cART but the researchers found no evidence for an association between the primary outcome and the pre-cART CD4 slope or between survival and this slope. In addition, the rate of CD4 cell count decline was not significantly associated with progression to AIDS or death among 1731 HIV-positive, symptom-free patients with CD4 cell counts above 350 cells/µl who were studied before cART was developed.
What Do These Findings Mean?
These findings suggest that knowledge of the rate of CD4 cell count decline will not improve the prediction of clinical outcome in HIV-positive patients with a CD4 cell count above 350 cells/µl. Indeed, the findings show that the rate of CD4 cell decline in individual patients is highly variable over time. Consequently, a rate measured at one time cannot be used to reliably predict a patient's future CD4 cell count. Because this was an observational study, patients with the greatest rate of decline in their CD4 cell count might have received better care than other patients, a possibility that would lessen the effect of the rate of CD4 cell count decline on outcomes. Nevertheless, the findings of this study strongly suggest that knowledge of the current CD4 cell count and an assessment of other established risk factors for progression to AIDS are sufficient when deciding whether to initiate cART in symptom-free HIV-positive patients.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000239.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including information on treatments and treatment guidelines
Information is available from Avert, an international AIDS charity, on all aspects of HIV/AIDS, including information on treatments for HIV and AIDS, when to start treatment, and the stages of HIV infection (in English and Spanish)
Information on CASCADE is available
doi:10.1371/journal.pmed.1000239
PMCID: PMC2826377  PMID: 20186270
21.  Life Expectancies of South African Adults Starting Antiretroviral Treatment: Collaborative Analysis of Cohort Studies 
PLoS Medicine  2013;10(4):e1001418.
Leigh Johnson and colleagues estimate the life expectancies of HIV positive South African adults who are taking antiretroviral therapy by using information from 6 programmes between 2001 and 2010.
Background
Few estimates exist of the life expectancy of HIV-positive adults receiving antiretroviral treatment (ART) in low- and middle-income countries. We aimed to estimate the life expectancy of patients starting ART in South Africa and compare it with that of HIV-negative adults.
Methods and Findings
Data were collected from six South African ART cohorts. Analysis was restricted to 37,740 HIV-positive adults starting ART for the first time. Estimates of mortality were obtained by linking patient records to the national population register. Relative survival models were used to estimate the excess mortality attributable to HIV by age, for different baseline CD4 categories and different durations. Non-HIV mortality was estimated using a South African demographic model. The average life expectancy of men starting ART varied between 27.6 y (95% CI: 25.2–30.2) at age 20 y and 10.1 y (95% CI: 9.3–10.8) at age 60 y, while estimates for women at the same ages were substantially higher, at 36.8 y (95% CI: 34.0–39.7) and 14.4 y (95% CI: 13.3–15.3), respectively. The life expectancy of a 20-y-old woman was 43.1 y (95% CI: 40.1–46.0) if her baseline CD4 count was ≥200 cells/µl, compared to 29.5 y (95% CI: 26.2–33.0) if her baseline CD4 count was <50 cells/µl. Life expectancies of patients with baseline CD4 counts ≥200 cells/µl were between 70% and 86% of those in HIV-negative adults of the same age and sex, and life expectancies were increased by 15%–20% in patients who had survived 2 y after starting ART. However, the analysis was limited by a lack of mortality data at longer durations.
Conclusions
South African HIV-positive adults can have a near-normal life expectancy, provided that they start ART before their CD4 count drops below 200 cells/µl. These findings demonstrate that the near-normal life expectancies of HIV-positive individuals receiving ART in high-income countries can apply to low- and middle-income countries as well.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
According to the latest figures, more than 34 million people worldwide currently live with HIV/AIDS. In 2011, an estimated 2.5 million people were newly infected with HIV, and in the same year 1.7 million people died from AIDS. Since the beginning of the epidemic in the 1980s, more than 60 million people have contracted HIV and nearly 30 million have died of HIV-related causes. Despite the stark statistics, the life expectancy for people infected with the AIDS virus has dramatically improved over the past decade since the introduction of an effective combination of antiretroviral drugs. In high-income countries, people who are HIV-positive can expect a near-normal life expectancy if they take these drugs (as antiretroviral treatment—ART) throughout their life.
Why Was This Study Done?
Recent studies investigating the life expectancy of people living with HIV have mostly focused on the situation in high-income settings. The situation in low- and middle-income countries is vastly different. People who are diagnosed with HIV are often late in starting treatment, treatments regimes are sometimes interrupted, and a large proportion of patients are lost to follow-up. It is important to gain a realistic estimate of life expectancy in low- and middle-income countries so patients can be given the best information. So in this study the researchers used a model to estimate the life expectancy of patients starting ART in South Africa, using data from several ART programs.
What Did the Researchers Do and Find?
The researchers used data collected from six programs in South Africa based in Western Cape, Gauteng, and KwaZulu-Natal between 2001 and 2010. The researchers calculated the observation time from the time of ART initiation to the date of death or to the end of the study. Then the researchers used a relative survival approach to model the excess mortality attributable to HIV, relative to non-HIV mortality rates in South Africa, over different periods from ART initiation.
Using these methods, the researchers found that over the time period, 37,740 adults started ART and 2,066 deaths were recorded in patient record systems. Of the 16,250 patients who were lost to follow-up, the researchers identified 2,947 further deaths in the population register. When they inputted these figures into their model, the researchers estimated that the mortality rate was 83.2 per 1,000 person-years of observation (PYO), and was higher in males (99.8 per 1,000 PYO) than in females (72.6 per 1,000 PYO). The researchers also found that the most significant factor determining the life expectancy of treated patients was their age at ART initiation: the average life expectancy of men starting ART varied between 27.6 years at age 20 and 10.1 years at age 60, while corresponding estimates in women were 36.8 and 14.4, respectively. Life expectancies were also significantly influenced by baseline CD4 counts; life expectancies in patients with baseline CD4 counts ≥200 cells/µl were between 70% and 86% of those of HIV-negative adults of the same age and sex, while patients starting ART with CD4 counts of <50 cells/µl had life expectancies that were between 48% and 61% of those of HIV-negative adults. Importantly, the researchers found that life expectancies were also 15%–20% higher in patients who survived their first 24 months after starting ART than in patients of the same age who had just started therapy.
What Do These Findings Mean?
These findings suggest that in South Africa, patients starting ART have life expectancies around 80% of normal life expectancy, provided that they start treatment before their CD4 count drops below 200 cells/µl. Although these results are encouraging, this study highlights that health services must overcome major challenges, such as dealing with late diagnosis, low uptake of CD4 testing, loss from pre-ART care, and delayed ART initiation, if near-normal life expectancies are to be achieved for the majority of HIV-positive South Africans. With the anticipated increase in the fraction of patients starting ART at higher CD4 counts in the future, long-term survival can be expected to increase even further. It is therefore critical that appropriate funding systems and innovative ways to reduce costs are put in place, to ensure the long-term sustainability of ART delivery in low- and middle-income countries.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001418.
The International Epidemiologic Databases to Evaluate AIDS has more statistical information from world regions
amfAR, the Foundation for AIDS Research, works with health care workers and AIDS organizations in developing countries to create and implement effective HIV research, treatment, prevention, and education strategies
doi:10.1371/journal.pmed.1001418
PMCID: PMC3621664  PMID: 23585736
22.  The Impact of Company-Level ART Provision to a Mining Workforce in South Africa: A Cost–Benefit Analysis 
PLoS Medicine  2015;12(9):e1001869.
Background
HIV impacts heavily on the operating costs of companies in sub-Saharan Africa, with many companies now providing antiretroviral therapy (ART) programmes in the workplace. A full cost–benefit analysis of workplace ART provision has not been conducted using primary data. We developed a dynamic health-state transition model to estimate the economic impact of HIV and the cost–benefit of ART provision in a mining company in South Africa between 2003 and 2022.
Methods and Findings
A dynamic health-state transition model, called the Workplace Impact Model (WIM), was parameterised with workplace data on workforce size, composition, turnover, HIV incidence, and CD4 cell count development. Bottom-up cost analyses from the employer perspective supplied data on inpatient and outpatient resource utilisation and the costs of absenteeism and replacement of sick workers. The model was fitted to workforce HIV prevalence and separation data while incorporating parameter uncertainty; univariate sensitivity analyses were used to assess the robustness of the model findings. As ART coverage increases from 10% to 97% of eligible employees, increases in survival and retention of HIV-positive employees and associated reductions in absenteeism and benefit payments lead to cost savings compared to a scenario of no treatment provision, with the annual cost of HIV to the company decreasing by 5% (90% credibility interval [CrI] 2%–8%) and the mean cost per HIV-positive employee decreasing by 14% (90% CrI 7%–19%) by 2022. This translates into an average saving of US$950,215 (90% CrI US$220,879–US$1.6 million) per year; 80% of these cost savings are due to reductions in benefit payments and inpatient care costs. Although findings are sensitive to assumptions regarding incidence and absenteeism, ART is cost-saving under considerable parameter uncertainty and in all tested scenarios, including when prevalence is reduced to 1%—except when no benefits were paid out to employees leaving the workforce and when absenteeism rates were half of what data suggested. Scaling up ART further through a universal test and treat strategy doubles savings; incorporating ART for family members reduces savings but is still marginally cost-saving compared to no treatment. Our analysis was limited to the direct cost of HIV to companies and did not examine the impact of HIV prevention policies on the miners or their families, and a few model inputs were based on limited data, though in sensitivity analysis our results were found to be robust to changes to these inputs along plausible ranges.
Conclusions
Workplace ART provision can be cost-saving for companies in high HIV prevalence settings due to reductions in healthcare costs, absenteeism, and staff turnover. Company-sponsored HIV counselling and voluntary testing with ensuing treatment of all HIV-positive employees and family members should be implemented universally at workplaces in countries with high HIV prevalence.
Gesine Meyer-Rath and colleagues assess whether workplace ART provision can be cost-saving for mining companies in high HIV prevalence settings.
Editors' Summary
Background
Every year, more than 2 million people become newly infected with HIV, the virus that causes AIDS, usually by having unprotected sex with an infected partner. People in the early stages of HIV infection rarely have any symptoms, but, over time, HIV destroys CD4 lymphocytes and other immune system cells, and, eventually, HIV-positive individuals become susceptible to numerous other infections. Because many of these infections are extremely serious, early in the AIDS epidemic, most HIV-infected individuals died within ten years of infection. Then, in 1996, effective antiretroviral therapy (ART)—cocktails of drugs that stop HIV replicating—became available. For people living in affluent countries, HIV/AIDS became a chronic condition, but because ART was expensive, HIV/AIDS remained fatal in low- and middle-income countries. In 2003, the international community began to work towards achieving universal access to ART. By 2013, nearly 13 million HIV-positive people—more than a third of the global HIV-infected population—had access to ART.
Why Was This Study Done?
HIV disease hits individuals in the prime of their working lives, thereby increasing absenteeism, the turnover of labor, and the operating costs of companies working in countries where HIV infection is common (high HIV prevalence). To reduce the economic impact of HIV/AIDS, some companies provide their workforces in such countries with comprehensive HIV services that include counseling and testing, and ART. For example, mining companies in South Africa (where nearly 20% of the working-age population is HIV-positive) provide HIV services to their workforces. However, although there is strong evidence that HIV disease increases the cost of doing business, a full cost–benefit analysis (the quantification of both the costs and benefits of a business strategy or medical intervention) of ART provision in the workplace based on real-world data has not been undertaken. Here, the researchers use a mathematical model to estimate the economic impact of HIV and the costs and benefits of company-level ART provision by a South African mining company between 2003 and 2022.
What Did the Researchers Do and Find?
The researchers developed a mathematical model to evaluate the past and future impact and costs to the employer of an ART program provided since 2002 by a coal mining company operating at a number of South African colleries. They fed data on the workforce’s characteristics, the annual number of new HIV infections in the workforce, the CD4 cell counts of HIV-positive employees, healthcare resource utilization, and the costs of absenteeism and labor turnover into the model. The model estimated that, as ART coverage increased from 10% to 97% of eligible employees, increases in the survival and retention of HIV-positive employees and reductions in absenteeism and benefit payments would lead to overall cost savings compared to a scenario of no ART provision. Specifically, the annual cost of HIV to the company would decrease by 5% and the average cost per HIV-positive employee would decrease by 14% by 2022. These changes in costs (which mainly accrue from reductions in benefit payments for death and ill-health retirement and in employee healthcare costs) translate into average savings of nearly US$1 million per year. Finally, scaling up ART coverage through a universal test and treat strategy would double savings, whereas providing ART for family members as well as employees would reduce savings but remain marginally cost-saving compared to no ART.
What Do These Findings Mean?
These findings suggest that workplace ART provision can be cost-saving for companies operating in settings with a high HIV prevalence because of reductions in healthcare costs, absenteeism, and staff turnover. That is, the costs to the employer of providing ART can be less than the costs saved by reducing healthcare use, absenteeism, and worker turnover. The accuracy of these findings depends on the quality of the data used to run the model. However, additional analyses indicate that ART provision is likely to be cost-saving unless people receive no benefits on leaving the workforce or the absenteeism rate is considerably lower than the available data suggest. Thus, the researchers propose that company-sponsored counseling and voluntary HIV testing with treatment of all HIV-positive employees and family members should be implemented universally at workplaces in countries with a high HIV prevalence. Such a strategy should be cost-saving for employers and might also take some pressure off resource-limited public sector ART programs.
Additional Information
This list of resources contains links that can be accessed when viewing the PDF on a device or via the online version of the article at http://dx.doi.org/10.1371/journal.pmed.1001869.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, summaries of recent research findings on HIV care and treatment, and personal stories about living with HIV/AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on ART, universal access to ART, and HIV/AIDS in South Africa; Avert also provides personal stories about living with HIV/AIDS
The World Health Organization provides information on all aspects of HIV/AIDS (in several languages), including its guidelines on the use of ART for treating and preventing HIV infection
The UNAIDS Fast-Track Strategy to End the AIDS Epidemic by 2030 provides up-to-date information about the AIDS epidemic and efforts to halt it; UNAIDS also provides detailed information about HIV/AIDS in South Africa
Wikipedia has a page about cost–benefit analysis (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
The HIV Modelling Consortium has a database of models used in analyzing the impact of HIV and ART, including models such as the one used in this analysis
The International AIDS Economics Network has a library of research on the economics of HIV around the world
doi:10.1371/journal.pmed.1001869
PMCID: PMC4556678  PMID: 26327271
23.  Recurrent tuberculosis in HIV-infected patients in Rio de Janeiro, Brazil 
AIDS (London, England)  2008;22(18):2527-2533.
Background/Objective
The risk of recurrent tuberculosis may increase in HIV-infected patients due to exogenous re-infection. We measured the frequency of and determined risk factors for recurrent tuberculosis in a cohort of HIV-infected patients in Rio de Janeiro, Brazil.
Methods
Data were abstracted from medical records of HIV-infected patients attending 29 HIV clinics between 1998 and 2007. Patients analyzed were those who had no tuberculosis history prior to their first HIV clinic visit and who had at least one episode of tuberculosis after entry. Incidence rate ratios compared incidence rates between risk groups and Cox proportional hazards regression models evaluated unadjusted and adjusted associations.
Results
Among 1,080 HIV-infected patients with tuberculosis, 96(8.9%) developed a recurrent diagnosis. The median time between diagnoses was 2.4 years. Fewer patients with recurrent tuberculosis had completed their initial 6-month course of tuberculosis treatment compared to patients without recurrence (78% versus 86%;p=0.02). For patients who completed therapy, the incidence rate of recurrence was 2.5/100 person years (PYs) versus 9.0/100PYs for non-completers (Incidence Rate Ratio (IRR)=3.60(95%CI:1.92-6.32). In multivariate modeling, initial tuberculosis treatment completion, receipt of antiretroviral therapy (ART) and CD4 cell count >200/mm3 any time after the initial diagnosis were associated with a significantly decreased hazard of recurrence.
Conclusions
Tuberculosis recurrence rates were high in this HIV-infected population. Completion of initial tuberculosis therapy, use of ART and increases in CD4 cell counts were associated with lower recurrence rates. Use of secondary preventive therapy might be warranted to reduce the burden of tuberculosis in patients with HIV infection.
doi:10.1097/QAD.0b013e328311ac4e
PMCID: PMC2603140  PMID: 19005276
HIV; tuberculosis; recurrence; antiretroviral therapy; Brazil
24.  Predicting Patterns of Long-Term CD4 Reconstitution in HIV-Infected Children Starting Antiretroviral Therapy in Sub-Saharan Africa: A Cohort-Based Modelling Study 
PLoS Medicine  2013;10(10):e1001542.
Using data from the ARROW trial, Joanna Lewis and colleagues investigate the CD4 cell count recovery profiles of children infected with HIV starting antiretroviral therapy in Sub-Saharan Africa.
Please see later in the article for the Editors' Summary
Background
Long-term immune reconstitution on antiretroviral therapy (ART) has important implications for HIV-infected children, who increasingly survive into adulthood. Children's response to ART differs from adults', and better descriptive and predictive models of reconstitution are needed to guide policy and direct research. We present statistical models characterising, qualitatively and quantitatively, patterns of long-term CD4 recovery.
Methods and Findings
CD4 counts every 12 wk over a median (interquartile range) of 4.0 (3.7, 4.4) y in 1,206 HIV-infected children, aged 0.4–17.6 y, starting ART in the Antiretroviral Research for Watoto trial (ISRCTN 24791884) were analysed in an exploratory analysis supplementary to the trial's pre-specified outcomes. Most (n = 914; 76%) children's CD4 counts rose quickly on ART to a constant age-corrected level. Using nonlinear mixed-effects models, higher long-term CD4 counts were predicted for children starting ART younger, and with higher CD4 counts (p<0.001). These results suggest that current World Health Organization–recommended CD4 thresholds for starting ART in children ≥5 y will result in lower CD4 counts in older children when they become adults, such that vertically infected children who remain ART-naïve beyond 10 y of age are unlikely ever to normalise CD4 count, regardless of CD4 count at ART initiation. CD4 profiles with four qualitatively distinct reconstitution patterns were seen in the remaining 292 (24%) children. Study limitations included incomplete viral load data, and that the uncertainty in allocating children to distinct reconstitution groups was not modelled.
Conclusions
Although younger ART-naïve children are at high risk of disease progression, they have good potential for achieving high CD4 counts on ART in later life provided ART is initiated following current World Health Organization (WHO), Paediatric European Network for Treatment of AIDS, or US Centers for Disease Control and Prevention guidelines. In contrast, to maximise CD4 reconstitution in treatment-naïve children >10 y, ART should ideally be considered even if there is a low risk of immediate disease progression. Further exploration of the immunological mechanisms for these CD4 recovery profiles should help guide management of paediatric HIV infection and optimise children's immunological development.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Worldwide, about 3.3 million children under 15 years old are infected with HIV, the virus that causes AIDS. More than 90% of these children live in sub-Saharan Africa, where nearly 600 children become infected with HIV every day, usually acquiring the virus from their mother during pregnancy, birth, or breastfeeding. HIV gradually reduces the numbers of CD4 lymphocytes in the immune system, leaving infected individuals susceptible to other infections. HIV infection can be kept in check but not cured with antiretroviral therapy (ART)—cocktails of drugs that have to be taken every day throughout life. ART reduces the amount of virus in the blood (viral load), which allows the immune system to recover (long-term immune reconstitution). Unfortunately, ART is very expensive, but concerted international efforts over the past decade mean that about a third of children who need ART are now receiving it, including half a million children in sub-Saharan Africa.
Why Was This Study Done?
World Health Organization (WHO) guidelines recommend initiation of ART at age-related CD4 cell count thresholds based on the risk of short-term disease progression. The guidelines recommend that all HIV-positive children under two years old begin ART as soon they receive a diagnosis of HIV infection. For children aged 2–5 years, ART initiation is recommended once the CD4 count drops below 750 cells/µl blood, whereas for older children the threshold for ART initiation is 350 CD4 cells/µl. Because of improved ART coverage, many more HIV-infected children now survive into adulthood than in the past. It is therefore important to know how the timing of ART initiation in childhood affects long-term immune reconstitution. Unfortunately, although several studies have examined the effect of ART on immune reconstitution in adults, the results of these studies cannot be extrapolated to children because of age-related differences in immune reconstitution. In this cohort-based modelling study, the researchers investigate long-term CD4 recovery in a cohort (group) of HIV-infected children initiating ART in Uganda and Zimbabwe, and present statistical models that predict patterns of long-term CD4 status based on age and CD4 count at ART initiation.
What Did the Researchers Do and Find?
To investigate long-term CD4 reconstitution in children, the researchers used CD4 counts collected during the ARROW trial, a study designed to investigate monitoring strategies during first-line ART in 1,206 HIV-positive children. In three-quarters of the children, CD4 reconstitution following ART initiation was asymptotic—CD4 counts increased rapidly immediately after ART initiation, then slowed before eventually reaching a constant level of about 80% of the CD4 count expected in an uninfected child of the same age. Using a nonlinear mixed-effects statistical model that fitted this pattern of immune reconstitution, the researchers predicted CD4 trajectories for children starting ART at different ages and with different CD4 counts. Higher long-term counts were predicted for children starting ART earlier and with higher CD4 counts. Thus, to achieve a CD4 count greater than 700 cells/µl at age 20 years, CD4 counts of at least 96 cells/µl, 130 cells/µl, and 557 cells/µl are needed for children aged two, five, and 12 years, respectively, when they initiate ART. Qualitatively distinct reconstitution patterns were seen in the remaining children in the study.
What Do These Findings Mean?
These findings suggest that young HIV-positive, ART-naïve children can achieve high CD4 counts in later life, provided ART is initiated as recommended in the current WHO guidelines. However, the recommended CD4 count thresholds for ART initiation are unlikely to maximize immune reconstitution in treatment-naïve children over ten years old. Rather, these findings suggest that ART initiation should be considered in these older children when their CD4 count is still high—even though they have a low risk of immediate disease progression—in order to achieve higher long-term CD4 levels. The omission of viral load measurements in the researchers' model may limit the accuracy of these findings. Moreover, although the predictions made by the model apply to children who will go on to experience asymptotic recovery, they are less relevant to those with different recovery profiles, who cannot currently be accurately identified. Further exploration of the immunological mechanisms underlying the CD4 recovery profiles described here should improve our understanding of the factors that determine the response of HIV-positive children to ART and provide information to guide the management of HIV infections in children.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001542.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV and AIDS in Africa and on HIV infection in children (in English and Spanish)
The UNAIDS World AIDS Day Report 2012 provides up-to-date information about the AIDS epidemic and efforts to halt it; the UNAIDS's 2013 Progress Report on the Global Plan provides information on progress towards eliminating new HIV infections among children by 2015
The World Health Organization provides information about universal access to AIDS treatment (in several languages); its 2010 guidelines for ART in infants and children can be downloaded
Information about the ARROW trial is available
Personal stories about living with HIV/AIDS, including stories from young people infected with HIV, are available through Avert, through Nam/aidsmap, and through the charity website Healthtalkonline
doi:10.1371/journal.pmed.1001542
PMCID: PMC3812080  PMID: 24204216
25.  Risk Factors and Outcomes for Late Presentation for HIV-Positive Persons in Europe: Results from the Collaboration of Observational HIV Epidemiological Research Europe Study (COHERE) 
PLoS Medicine  2013;10(9):e1001510.
Amanda Mocroft and colleagues investigate risk factors and health outcomes associated with diagnosis at a late stage of infection in individuals across Europe.
Please see later in the article for the Editors' Summary
Background
Few studies have monitored late presentation (LP) of HIV infection over the European continent, including Eastern Europe. Study objectives were to explore the impact of LP on AIDS and mortality.
Methods and Findings
LP was defined in Collaboration of Observational HIV Epidemiological Research Europe (COHERE) as HIV diagnosis with a CD4 count <350/mm3 or an AIDS diagnosis within 6 months of HIV diagnosis among persons presenting for care between 1 January 2000 and 30 June 2011. Logistic regression was used to identify factors associated with LP and Poisson regression to explore the impact on AIDS/death. 84,524 individuals from 23 cohorts in 35 countries contributed data; 45,488 were LP (53.8%). LP was highest in heterosexual males (66.1%), Southern European countries (57.0%), and persons originating from Africa (65.1%). LP decreased from 57.3% in 2000 to 51.7% in 2010/2011 (adjusted odds ratio [aOR] 0.96; 95% CI 0.95–0.97). LP decreased over time in both Central and Northern Europe among homosexual men, and male and female heterosexuals, but increased over time for female heterosexuals and male intravenous drug users (IDUs) from Southern Europe and in male and female IDUs from Eastern Europe. 8,187 AIDS/deaths occurred during 327,003 person-years of follow-up. In the first year after HIV diagnosis, LP was associated with over a 13-fold increased incidence of AIDS/death in Southern Europe (adjusted incidence rate ratio [aIRR] 13.02; 95% CI 8.19–20.70) and over a 6-fold increased rate in Eastern Europe (aIRR 6.64; 95% CI 3.55–12.43).
Conclusions
LP has decreased over time across Europe, but remains a significant issue in the region in all HIV exposure groups. LP increased in male IDUs and female heterosexuals from Southern Europe and IDUs in Eastern Europe. LP was associated with an increased rate of AIDS/deaths, particularly in the first year after HIV diagnosis, with significant variation across Europe. Earlier and more widespread testing, timely referrals after testing positive, and improved retention in care strategies are required to further reduce the incidence of LP.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Every year about 2.5 million people become newly infected with HIV, the virus that causes AIDS. HIV can be transmitted through unprotected sex with an infected partner, from an HIV-positive mother to her unborn baby, or through injection of drugs. Most people do not become ill immediately after infection with HIV although some develop a short influenza-like illness. The next stage of the HIV infection, which may last up to 10 years, also has no major symptoms but, during this stage, HIV slowly destroys immune system cells, including CD4 cells, a type of lymphocyte. Eventually, when the immune system is unable to fight off infections by other disease-causing organisms, HIV-positive people develop AIDS-defining conditions—unusual viral, bacterial, and fungal infections and unusual tumors. Progression to AIDS occurs when any severe AIDS-defining condition is diagnosed, when the CD4 count in the blood falls below 200 cells/mm3, or when CD4 cells account for fewer than 15% of lymphocytes.
Why Was This Study Done?
People need to know they are HIV positive as soon as possible after they become infected because antiretroviral therapy, which controls but does not cure HIV infection, works best if it is initiated when people still have a relatively high CD4 count. Early diagnosis also reduces the risk of onward HIV transmission. However, 40%–60% of HIV-positive individuals in developed countries are not diagnosed until they have a low CD4 count or an AIDS-defining illness. Reasons for such late presentation include fear of discrimination or stigmatization, limited knowledge about HIV risk factors, testing, and treatment together with missed opportunities to offer an HIV test. Policy makers involved in national and international HIV control programs need detailed information about patterns of late presentation before they can make informed decisions about how to reduce this problem. In this study, therefore, the researchers use data collected by the Collaboration of Observational HIV Epidemiological Research in Europe (COHERE) to analyze trends in late presentation over time across Europe and in different groups of people at risk of HIV infection and to investigate the clinical consequences of late presentation.
What Did the Researchers Do and Find?
The researchers analyzed data collected from 84,524 individuals participating in more than 20 observational studies that were undertaken in 35 European countries and that investigated outcomes among HIV-positive people. Nearly 54% of the participants were late presenters—individuals who had a CD4 count of less than 350 cells/mm3 or an AIDS-defining illness within 6 months of HIV diagnosis. Late presentation was highest among heterosexual males, in Southern European countries, and among people originating in Africa. Overall, late presentation decreased from 57.3% in 2000 to 51.7% in 2010/11. However, whereas late presentation decreased over time among men having sex with men in Central and Northern Europe, for example, it increased over time among female heterosexuals in Southern Europe. Finally, among the 8,000 individuals who developed a new AIDS-defining illness or died during follow-up, compared to non-late presentation, late presentation was associated with an increased incidence of AIDS/death in all regions of Europe during the first and second year after HIV diagnosis (but not in later years); the largest increase in incidence (13-fold) occurred during the first year after diagnosis in Southern Europe.
What Do These Findings Mean?
These findings indicate that, although late presentation with HIV infection has decreased in recent years, it remains an important issue across Europe and in all groups of people at risk of HIV infection. They also show that individuals presenting late have a worse clinical outlook, particularly in the first and second year after diagnosis compared to non-late presenters. Several aspects of the study design may affect the accuracy and usefulness of these findings, however. For example, some of the study participants recorded as late presenters may have been people who were aware of their HIV status but who chose not to seek care for HIV infection, or may have been seen in the health care system prior to HIV diagnosis without being offered an HIV test. Delayed entry into care and late presentation are likely to have different risk factors, a possibility that needs to be studied further. Despite this and other study limitations, these findings nevertheless suggest that HIV testing strategies that encourage early testing in all populations at risk, that ensure timely referrals, and that improve retention in care are required to further reduce the incidence of late presentation with HIV infection in Europe.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/ 10.1371/journal.pmed.1001510.
Information is available from the US National Institute of Allergy and infectious diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including detailed information on the stages of HIV infection and on HIV and AIDS in Europe (in English and Spanish)
The HIV in Europe Initiative has information about strategies to improve earlier diagnosis and access to care in Europe
Information about COHERE, which was established in 2005 to conduct epidemiological research on the prognosis and outcome of HIV-infected people from across Europe, is available; more information on the consensus definition of late presentation used in this study is available through the HIV in Europe initiative
Patient stories about living with HIV/AIDS are available through Avert and through the nonprofit website Healthtalkonline
doi:10.1371/journal.pmed.1001510
PMCID: PMC3796947  PMID: 24137103

Results 1-25 (1317918)