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1.  Metabolic Abnormalities and Viral Replication is Associated with Biomarkers of Vascular Dysfunction in HIV-Infected Children 
HIV Medicine  2011;13(5):264-275.
Objectives
Human immunodeficiency virus (HIV)-infected children may be at risk for premature cardiovascular disease. We compared levels of biomarkers of vascular dysfunction among HIV-infected children with and without hyperlipidemia to HIV-exposed, uninfected children (HEU) enrolled in the Pediatric HIV/AIDS Cohort Study (PHACS), and determined factors associated with these biomarkers.
Design
Prospective cohort study
Methods
Biomarkers of inflammation (C-reactive protein (CRP), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP1)); coagulant dysfunction (fibrinogen and P-selectin); endothelial dysfunction (soluble intracellular cell adhesion molecule-1 (sICAM), soluble vascular cell adhesion molecule-1 (sVCAM), and E-selectin); and metabolic dysfunction (adiponectin) were measured in 226 HIV-infected and 140 HEU children. Anthropometry, body composition, lipids, glucose, insulin, HIV disease severity, and antiretroviral therapy were recorded.
Results
The median ages were 12.3 y (HIV-infected) and 10.1 y (HEU). Body mass index (BMI) Z-scores, waist and hip circumference, and percent body fat were lower among HIV-infected. Total and non-HDL cholesterol and triglycerides were higher in HIV-infected children. HIV-infected children had higher MCP-1, fibrinogen, sICAM, and sVCAM levels. In multivariable analyses in the HIV-infected children alone, BMI z-score was associated with higher CRP and fibrinogen, but lower MCP-1 and sVCAM. Unfavorable lipid profiles were positively associated with IL6, MCP1, fibrinogen, and P- and E-selectin, whereas increased HIV viral load was associated with markers of inflammation (MCP1 and CRP) and endothelial dysfunction (sICAM and sVCAM).
Conclusions
HIV-infected children have higher levels of biomarkers of vascular dysfunction than do HEU children. Risk factors associated with higher biomarkers include unfavorable lipid levels and active HIV replication.
doi:10.1111/j.1468-1293.2011.00970.x
PMCID: PMC3297698  PMID: 22136114
Children; HIV/AIDS; vascular dysfunction; cardiovascular risk factors; biomarkers
2.  Markers of coagulation and inflammation often remain elevated in ART-treated HIV-infected patients 
Purpose of review
Current antiretroviral therapies have dramatically changed the disease course of HIV infection. While antiretroviral therapy (ART) is effective at decreasing viral replication and preserving CD4+ T cell numbers, low-level immune activation and inflammation persist in virally suppressed HIV-infected patients. This chronic immune activation/inflammation may contribute to an increased risk for venous and arterial thrombosis.
Recent findings
Several markers of coagulation and inflammation are increased in HIV-infected patients. The Strategies for the Management of Antiretroviral Therapy (SMART) study reported that plasma D-dimer levels, a marker of fibrinolysis, independently predicted morbidity in HIV-infected patients. Increased plasma and cell surface levels of the procoagulant tissue factor (TF) have also been reported in patients with HIV disease. Fibrinogen, von Willebrand factor (vWf), and P-selectin are likewise increased in plasma samples of HIV-infected patients; all of these markers suggest HIV-infection results in a pro-coagulant state. Treatment with antiretroviral therapy reduces, but does not always normalize, levels of biomarkers associated with inflammation and coagulation in HIV+ patients.
Summary
HIV-infected patients are at greater risk for both venous and arterial thrombosis. Chronic immune activation and inflammation in these patients appears to contribute to coagulation risk. Antiretroviral therapy reduces viral replication, immune activation, and markers of coagulation, but these indices do not always return to normal, even after several years of viremic control.
doi:10.1097/COH.0000000000000019
PMCID: PMC3982388  PMID: 24275673
coagulation; D-dimer; antiretroviral therapy; inflammation
3.  Biomarkers of Vascular Dysfunction in Children Infected with Human Immunodeficiency Virus-1 
Background
We compared biomarkers of vascular dysfunction among HIV-infected children to a demographically-similar group of uninfected children and determined factors associated with these biomarkers.
Methods and Results
We measured several biomarkers of vascular dysfunction: C-Reactive Protein (CRP), interleukin-6 (IL-6), and monocyte chemoattractant protein -1 (MCP1) [inflammation]; fibrinogen and P-selectin [coagulant dysfunction]; soluble intracellular cell adhesion molecule-1 (sICAM), soluble vascular cell adhesion molecule-1 (sVCAM), and E-selectin [endothelial dysfunction]; and leptin [metabolic dysfunction]. Anthropometry, body composition, CD4%, HIV viral load, and antiretroviral therapy were recorded. Mean age was 14.8y [106 HIV-infected children] and 12.3y [55 control children]. Sex and body mass index Z-scores were similar. Infected children had higher sICAM, sVCAM, MCP1, IL-6, and fibrinogen levels. E-selectin (p=0.07), and CRP (p=0.08) trended to be greater in the HIV group, yet leptin, and P-selectin were similar. In multivariable analyses in the HIV-infected children alone, each 1-standard-deviation increase in waist:hip ratio was associated with increases in sICAM (17%), MCP1 (19%), IL6 (18%), and CRP (59%). CD4% was inversely associated with sVCAM, MCP1, IL6, fibrinogen, and CRP.
Conclusion
HIV-infected children have higher levels of biomarkers of vascular dysfunction than healthy children. Risk factors associated with these biomarkers include higher waist:hip ratios and HIV disease severity.
doi:10.1097/QAI.0b013e3181e222c9
PMCID: PMC2943965  PMID: 20531209
Children; HIV/AIDS; vascular dysfunction; cardiovascular risk factors; biomarkers
4.  Relationship between innate immunity, soluble markers and metabolic-clinical parameters in HIV+ patients ART treated with HIV-RNA<50 cp/mL 
Journal of the International AIDS Society  2014;17(4Suppl 3):19718.
Introduction
The persistence of immune activation and inflammation in HIV patients with HIV-RNA (VL) undetectable causes many co-morbidities [1–3]. The aim of this study is to correlate monocytes (m) and NK cell activation levels, soluble markers and oxidative stress with clinical, biochemical and metabolic data in HIV-1 infected patients with VL≤50 copies (cp)/mL on antiretroviral therapy.
Materials and Methods
Multicentre, cross-sectional study in patients with VL≤50 cp/mL and on antiretroviral therapy by at least six months. We studied: activation/homing markers (CD38, HLA-DR, CCR-2, PDL-1) on inflammatory, intermediate, proinflammatory m; activatory receptors NKp30, NKp46 and HLA-DR on NK cells; soluble inflammatory (sCD14, adiponectina, MCP-1) and stress oxidative markers (dRoms, antiRoms). Univariate analyses are performed with non-parametric and Pearson tests. The significant correlations were adjusted for possible known confounding factors (smoking, Cytomegalovirus IgG serology, Raltegravir, Protease Inhibitor [PI] therapy and HCV-RNA) with multivariate analysis.
Results
In the 68 patients the positive correlation between age and antiRoms was significant also after adjustment for PI use (p=0.05). The% CD8+T was associated with% proinflammatory m (p=0.043) and with their expression of CCR2 mean fluorescence intensity (MFI) (p=0.012). The% NKp46+ was positively correlated with CD4+T count (p=0.001). The fibrinogen was positively associated with dRoms (p=0.052) and the positive correlation between triglycerides and antiRoms has been confirmed (p<0.001); the impact of antiRoms on HDL/triglycerides ratio (p=0.006) was observed after adjustment for PI use. The BMI was associated with smoking (p=0.011). Only the maraviroc-treated patients showed minimal arterial pressure, fibrinogen and antiRoms lower (p=0.001, 0.004 e 0.006) and sCD14 values higher (p=0.029).
Conclusions
Patients with long history of HIV infection and stable immunological and virological status showed interactions between acquired and innate immunity activation; moreover, the levels of some metabolic and inflammatory parameters correlate with oxidative stress values and innate immunity activation. The age, BMI and smoking impact metabolic and immunological parameters. The correlations between antiretroviral drugs and clinical-immunological parameters need further confirmations.
doi:10.7448/IAS.17.4.19718
PMCID: PMC4225419  PMID: 25397464
5.  HIV: prevention of mother-to-child transmission  
Clinical Evidence  2011;2011:0909.
Introduction
Over 2 million children are thought to be living with HIV/AIDS worldwide, of whom over 80% live in sub-Saharan Africa. Without antiretroviral treatment, the risk of HIV transmission from infected mothers to their children is 15% to 30% during gestation or labour, with an additional transmission risk of 10% to 20% associated with prolonged breastfeeding. HIV-1 infection accounts for most infections; HIV-2 is rarely transmitted from mother to child. Transmission is more likely in mothers with high viral loads, advanced disease, or both, in the presence of other sexually transmitted diseases, and with increased exposure to maternal blood. Mixed feeding practices (breast milk plus other liquids or solids) and prolonged breastfeeding are also associated with increased risk of mother-to-child transmission of HIV.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical question: What are the effects of measures to reduce mother-to-child transmission of HIV? We searched: Medline, Embase, The Cochrane Library, and other important databases up to October 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We performed a GRADE evaluation of the quality of evidence for interventions.
Results
We found 53 systematic reviews, RCTs, or observational studies that met our inclusion criteria.
Conclusions
In this systematic review we present information relating to the effectiveness and safety of the following interventions: antiretroviral drugs, different methods of infant feeding, elective caesarean section, immunotherapy, micronutrient supplements, vaginal microbicides, and vitamin supplements.
Key Points
Without active intervention, the risk of mother-to-child transmission (MTCT) of HIV-1 is high, especially in populations where prolonged breastfeeding is the norm. Without antiviral treatment, the risk of transmission of HIV from infected mothers to their children is approximately 15% to 30% during pregnancy and labour, with an additional transmission risk of 10% to 20% associated with prolonged breastfeeding.HIV-2 is rarely transmitted from mother to child.Transmission is more likely in mothers with high viral loads, advanced HIV disease, or both.Without antiretroviral treatment (ART), 15% to 35% of vertically infected infants die within the first year of life.The long-term treatment of children with ART is complicated by multiple concerns regarding the complications associated with life-long treatment, including adverse effects of antiretroviral drugs, difficulties of adherence across the developmental trajectory of childhood and adolescence, and the development of resistance.From a paediatric perspective, successful prevention of MTCT and HIV-free survival for infants remain the most important focus.
Antiretroviral drugs given to the mother during pregnancy or labour, to the baby immediately after birth, or to the mother and baby reduce the risk of intrauterine and intrapartum MTCT of HIV-1 and when given to the infant after birth and to the mother or infant during breastfeeding reduce the risk of postpartum MTCT of HIV-1.
Reductions in MTCT are possible using multidrug ART regimens. Longer courses of ART are more effective, but the greatest benefit is derived from treatment during late pregnancy, labour, and early infancy.Suppression of the maternal viral load to undetectable levels (below 50 copies/mL) using highly active antiretroviral therapy (HAART) offers the greatest risk reduction, and is currently the standard of care offered in most resource-rich countries, where MTCT rates have been reduced to 1% to 2%. Alternative short-course regimens have been tested in resource-limited settings where HAART is not yet widely available. There is evidence that short courses of antiretroviral drugs have confirmed efficacy for reducing MTCT. Identifying optimal short-course regimens (drug combination, timing, and cost effectiveness) for various settings remains a focus for ongoing research.The development of viral resistance in mothers and infants after single-dose nevirapine and other short-course regimens that include single-dose nevirapine is of concern. An additional short-course of antiretrovirals with a different regimen during labour and early postpartum, and the use of HAART, may decrease the risk of viral resistance in mothers, and in infants who become HIV-infected despite prophylaxis.World Health Organization guidelines recommend starting prophylaxis with antiretroviral drugs from as early as 14 weeks' gestation, or as soon as possible if women present late in pregnancy, in labour, or at delivery.
Elective caesarean section at 38 weeks may reduce vertical transmission rates (apart from breast-milk transmission). The potential benefits of this intervention need to be balanced against the increased risk of surgery-associated complications, high cost, and feasibility issues. These reservations are particularly relevant in resource-limited settings.
Immunotherapy with HIV hyperimmune globulin seems no more effective than immunoglobulin without HIV antibody at reducing HIV-1 MTCT risk.
Vaginal microbicides have not been demonstrated to reduce HIV-1 MTCT risk.
There is no evidence that supplementation with vitamin A reduces the risk of HIV-1 MTCT, and there is concern that postnatal vitamin A supplementation for mother and infant may be associated with increased risk of mortality.
We don't know whether micronutrients are effective in prevention of MTCT of HIV as we found no RCT evidence on this outcome.
Avoidance of breastfeeding prevents postpartum transmission of HIV, but formula feeding requires access to clean water and health education. The risk of breastfeeding-related HIV transmission needs to be balanced against the multiple benefits that breastfeeding offers. In resource-poor countries, breastfeeding is strongly associated with reduced infant morbidity and improved child survival. Exclusive breastfeeding during the first 6 months may reduce the risk of HIV transmission compared with mixed feeding, while retaining most of its associated benefits.In a population where prolonged breastfeeding is usual, early, abrupt weaning may not reduce MTCT or HIV-free survival at 2 years compared with prolonged breastfeeding, and may be associated with a higher rate of infant mortality for those infants diagnosed as HIV-infected at <4 months of age. Antiretrovirals given to the mother or the infant during breastfeeding can reduce the risk of HIV transmission in the postpartum period. World Health Organization guidelines recommend that HIV-positive mothers should exclusively breastfeed for the first 6 months, after which time appropriate complementary foods can be introduced. Breastfeeding should be continued for the first 12 months of the infant's life, and stopped only when an adequate diet without breast milk can be provided. Heat- or microbicidal-treated expressed breast milk may offer value in particular settings.
PMCID: PMC3217724  PMID: 21477392
6.  Markers of inflammation and coagulation indicate a prothrombotic state in HIV-infected patients with long-term use of antiretroviral therapy with or without abacavir 
Background
Abacavir (ABC) treatment has been associated with an increased incidence of myocardial infarction. The pathophysiological mechanism is unknown. In this study markers of inflammation and coagulation in HIV-infected patients using antiretroviral therapy with or without ABC were examined to pinpoint a pathogenic mechanism. Given the important role of high sensitivity C-reactive protein (hsCRP) levels in predicting cardiovascular risk, patient groups were also analyzed according to hsCRP levels.
Methods
Patients treated with ABC and a matched control group treated without ABC were selected retrospectively. Vascular endothelial growth factor (VEGF) and markers of endothelial cell activation (von Willebrand factor (vWF), factor VIII), fibrin formation (fibrinogen, D-dimer, prothrombin fragment 1+2 (F1+2), endogenous thrombin potential (ETP)), anticoagulation markers (protein C and S, activated protein C sensitivity ratio (APCsr)) and inflammation markers (IL-6, hsCRP) were measured in citrated plasma.
Results
A total of 81 patients were included of whom 27 patients used an ABC-containing regimen and 54 used a non-ABC-containing regimen. Patient characteristics were not significantly different between the groups except for longer duration of use of the current antiretroviral regimen in the ABC group (p = 0.01). The median time on ABC was 68 months (interquartile range 59-80 months). No differences in coagulation and inflammation markers according to ABC use were observed. For the whole patient group elevated vWF and F1+2 levels were observed in 23% and 37%, respectively. Compared to the reference ranges for the general population increased APCsr was found in 79% and lower protein C and VEGF levels in 40% and 43%, respectively. Patients in the high-risk category for cardiovascular disease with hsCRP levels > 3 mg/L had significantly higher fibrinogen, D-dimer, F1+2 and ETP levels compared to patients from the low-risk category with hsCRP levels < 1 mg/L.
Conclusion
HIV-infected patients using ABC showed no specific abnormalities in coagulation or inflammation markers that might explain the increased risk of myocardial infarction. For the whole group, regardless of ABC use, evidence of a prothrombotic state was observed. Thirty-three percent of patients with long-term use of antiretroviral treatment had hsCRP levels above 3 mg/L, which is strongly associated with cardiovascular disease in HIV-uninfected individuals.
doi:10.1186/1742-6405-7-9
PMCID: PMC2873236  PMID: 20398387
7.  Kidney and liver organ transplantation in persons with human immunodeficiency virus 
Executive Summary
Objective
The objective of this analysis is to determine the effectiveness of solid organ transplantation in persons with end stage organ failure (ESOF) and human immunodeficiency virus (HIV+)
Clinical Need: Condition and Target Population
Patients with end stage organ failure who have been unresponsive to other forms of treatment eventually require solid organ transplantation. Similar to persons who are HIV negative (HIV−), persons living with HIV infection (HIV+) are at risk for ESOF from viral (e.g. hepatitis B and C) and non-viral aetiologies (e.g. coronary artery disease, diabetes, hepatocellular carcinoma). Additionally, HIV+ persons also incur risks of ESOF from HIV-associated nephropathy (HIVAN), accelerated liver damage from hepatitis C virus (HCV+), with which an estimated 30% of HIV positive (HIV+) persons are co-infected, and coronary artery disease secondary to antiretroviral therapy. Concerns that the need for post transplant immunosuppression and/or the interaction of immunosuppressive drugs with antiretroviral agents may accelerate the progression of HIV disease, as well as the risk of opportunistic infections post transplantation, have led to uncertainty regarding the overall benefit of transplantation among HIV+ patients. Moreover, the scarcity of donor organs and their use in a population where the clinical benefit of transplantation is uncertain has limited the availability of organ transplantation to persons living with ESOF and HIV.
With the development of highly active anti retroviral therapy (HAART), which has been available in Canada since 1997, there has been improved survival and health-related quality of life for persons living with HIV. HAART can suppress HIV replication, enhance immune function, and slow disease progression. HAART managed persons can now be expected to live longer than those in the pre-HAART era and as a result many will now experience ESOF well before they experience life-threatening conditions related to HIV infection. Given their improved prognosis and the burden of illness they may experience from ESOF, the benefit of solid organ transplantation for HIV+ patients needs to be reassessed.
Evidence-Based Analysis Methods
Research Questions
What are the effectiveness and cost effectiveness of solid organ transplantation in HIV+ persons with ESOF?
Literature Search
A literature search was performed on September 22, 2009 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 1996 to September 22, 2009.
Inclusion Criteria
Systematic review with or without a Meta analysis, RCT, Non-RCT with controls
HIV+ population undergoing solid organ transplantation
HIV+ population managed with HAART therapy
Controls include persons undergoing solid organ transplantation who are i) HIV− ii) HCV+ mono-infected, and iii) HIV+ persons with ESOF not transplanted.
Studies that completed and reported results of a Kaplan-Meier Survival Curve analysis.
Studies with a minimum (mean or medium) follow up of 1-year.
English language citations
Exclusion Criteria
Case reports and case series were excluded form this review.
Outcomes of Interest
i) Risk of Death after transplantation
ii) Death censored graft survival (DCGS)
iii) HIV disease progression defined as the post transplant incidence of:
- opportunistic infections or neoplasms,
- CD4+ T-cell count < 200mm3, and
- any detectable level of plasma HIV viral load.
iv) Acute graft rejection,
v) Return to dialysis,
vi) Recurrence of HCV infection
Summary of Findings
No direct evidence comparing an HIV+ cohort undergoing transplantation with the same not undergoing transplantation (wait list) was found in the literature search.
The results of this review are reported for the following comparison cohorts undergoing transplantation:
i) Kidney Transplantation: HIV+ cohort compared with HIV− cohort
ii) Liver Transplantation: HIV+ cohort compared with HIV− negative cohort
iii) Liver Transplantation: HIV+ HCV+ (co-infected) cohort compared with HCV+ (mono-infected) cohort
Kidney Transplantation: HIV+ vs. HIV−
Based on a pooled HIV+ cohort sample size of 285 patients across four studies, the risk of death after kidney transplantation in an HIV+ cohort does not differ to that of an HIV− cohort [hazard ratio (HR): 0.90; 95% CI: 0.36, 2.23]. The quality of evidence supporting this outcome is very low.
Death censored graft survival was reported in one study with an HIV+ cohort sample size of 100, and was statistically significantly different (p=.03) to that in the HIV− cohort (n=36,492). However, the quality of evidence supporting this outcome was determined to be very low. There was also uncertainty in the rate of return to dialysis after kidney transplantation in both the HIV+ and HIV− groups and the effect, if any, this may have on patient survival. Because of the very low quality evidence rating, the effect of kidney transplantation on HIV-disease progression is uncertain.
The rate of acute graft rejection was determined using the data from one study. There was a nonsignificant difference between the HIV+ and HIV− cohorts (OR 0.13; 95% CI: 0.01, 2.64), although again, because of very low quality evidence there is uncertainty in this estimate of effect.
Liver Transplantation: HIV+ vs. HIV−
Based on a combined HIV+ cohort sample size of 198 patient across five studies, the risk of death after liver transplantation in an HIV+ cohort (with at least 50% of the cohort co-infected with HCV+) is statistically significantly 64% greater compared with an HIV− cohort (HR: 1.64; 95% CI: 1.32, 2.02). The quality of evidence supporting this outcome is very low.
Death censored graft survival was reported for an HIV+ cohort in one study (n=11) however the DCGS rate of the contemporaneous control HIV− cohort was not reported. Because of sparse data the quality of evidence supporting this outcome is very low indicating death censored graft survival is uncertain.
Both the CD4+ T-cell count and HIV viral load appear controlled post transplant with an incidence of opportunistic infection of 20.5%. However, the quality of this evidence for these outcomes is very low indicating uncertainty in these effects. Similarly, because of very low quality evidence there is uncertainty in the rate of acute graft rejection among both the HIV+ and HIV− groups
Liver Transplantation: HIV+/HCV+ vs. HCV+
Based on a combined HIV+/HCV+ cohort sample size of 156 from seven studies, the risk of death after liver transplantation is significantly greater (2.8 fold) in a co-infected cohort compared with an HCV+ mono-infected cohort (HR: 2.81; 95% CI: 1.47, 5.37). The quality of evidence supporting this outcome is very low. Death censored graft survival evidence was not available.
Regarding disease progression, based on a combined sample size of 71 persons in the co-infected cohort, the CD4+ T-cell count and HIV viral load appear controlled post transplant; however, again the quality of evidence supporting this outcome is very low. The rate of opportunistic infection in the co-infected cohort was 7.2%. The quality of evidence supporting this estimate is very low, indicating uncertainty in these estimates of effect.
Based on a combined HIV+/HCV+ cohort (n=57) the rate of acute graft rejection does not differ to that of an HCV+ mono-infected cohort (OR: 0.88; 95% CI: 0.44, 1.76). Also based on a combined HIV+/HCV+ cohort (n=83), the rate of HCV+ recurrence does not differ to that of an HCV+ mono-infected cohort (OR: 0.66; 95% CI: 0.27, 1.59). In both cases, the quality of the supporting evidence was very low.
Overall, because of very low quality evidence there is uncertainty in the effect of kidney or liver transplantation in HIV+ persons with end stage organ failure compared with those not infected with HIV. Examining the economics of this issue, the cost of kidney and liver transplants in an HIV+ patient population are, on average, 56K and 147K per case, based on both Canadian and American experiences.
PMCID: PMC3377507  PMID: 23074407
8.  Bacterial Vaginosis Associated with Increased Risk of Female-to-Male HIV-1 Transmission: A Prospective Cohort Analysis among African Couples 
PLoS Medicine  2012;9(6):e1001251.
In a prospective study, Craig Cohen and colleagues investigate the association between bacterial vaginosis and the risk of female-to-male HIV-1 transmission.
Background
Bacterial vaginosis (BV), a disruption of the normal vaginal flora, has been associated with a 60% increased risk of HIV-1 acquisition in women and higher concentration of HIV-1 RNA in the genital tract of HIV-1–infected women. However, whether BV, which is present in up to half of African HIV-1–infected women, is associated with an increase in HIV-1 transmission to male partners has not been assessed in previous studies.
Methods and Findings
We assessed the association between BV on female-to-male HIV-1 transmission risk in a prospective study of 2,236 HIV-1–seropositive women and their HIV-1 uninfected male partners from seven African countries from a randomized placebo-controlled trial that enrolled heterosexual African adults who were seropositive for both HIV-1 and herpes simplex virus (HSV)-2, and their HIV-1–seronegative partners. Participants were followed for up to 24 months; every three months, vaginal swabs were obtained from female partners for Gram stain and male partners were tested for HIV-1. BV and normal vaginal flora were defined as a Nugent score of 7–10 and 0–3, respectively. To reduce misclassification, HIV-1 sequence analysis of viruses from seroconverters and their partners was performed to determine linkage of HIV-1 transmissions. Overall, 50 incident HIV-1 infections occurred in men in which the HIV-1–infected female partner had an evaluable vaginal Gram stain. HIV-1 incidence in men whose HIV-1–infected female partners had BV was 2.91 versus 0.76 per 100 person-years in men whose female partners had normal vaginal flora (hazard ratio 3.62, 95% CI 1.74–7.52). After controlling for sociodemographic factors, sexual behavior, male circumcision, sexually transmitted infections, pregnancy, and plasma HIV-1 RNA levels in female partners, BV was associated with a greater than 3-fold increased risk of female-to-male HIV-1 transmission (adjusted hazard ratio 3.17, 95% CI 1.37–7.33).
Conclusions
This study identified an association between BV and increased risk of HIV-1 transmission to male partners. Several limitations may affect the generalizability of our results including: all participants underwent couples HIV counseling and testing and enrolled in an HIV-1 prevention trial, and index participants had a baseline CD4 count ≥250 cells/mm3 and were HSV-2 seropositive. Given the high prevalence of BV and the association of BV with increased risk of both female HIV-1 acquisition and transmission found in our study, if this association proves to be causal, BV could be responsible for a substantial proportion of new HIV-1 infections in Africa. Normalization of vaginal flora in HIV-1–infected women could mitigate female-to-male HIV-1 transmission.
Trial Registration: ClinicalTrials.com NCT00194519
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Since the first reported case of AIDS in 1981, the number of people infected with HIV, the virus that causes AIDS, has risen steadily. By the end of 2010, 34 million people were living with HIV/AIDS. At the beginning of the epidemic more men than women were infected with HIV. Now, however, 50% of all adults infected with HIV are women and in sub-Saharan Africa, where two-thirds of HIV-positive people live, women account for 59% of people living with HIV. Moreover, among 15–24 year-olds, women are eight times more likely than men to be HIV-positive. This pattern of infection has developed because most people in sub-Saharan Africa contract HIV through unprotected heterosexual sex. The risk of HIV transmission for both men and women in Africa and elsewhere can be reduced by abstaining from sex, by only having one or a few partners, by always using condoms, and by male circumcision. In addition, several studies suggest that antiretroviral therapy (ART) greatly reduces HIV transmission.
Why Was This Study Done?
Unfortunately, in sub-Saharan Africa, only about a fifth of HIV-positive people are currently receiving ART, which means that there is an urgent need to find other effective ways to reduce HIV transmission in this region. In this prospective cohort study (a type of study that follows a group of people for some time to see which personal characteristics are associated with disease development), the researchers investigate whether bacterial vaginosis—a condition in which harmful bacteria disrupt the normal vaginal flora—increases the risk of female-to-male HIV transmission among African couples. Bacterial vaginosis, which is extremely common in sub-Saharan Africa, has been associated with an increased risk of HIV acquisition in women and induces viral replication and shedding in the vagina in HIV-positive women, which may mean that HIV-positive women with bacterial vaginosis are more likely to transmit HIV to their male partners than women without this condition. If this is the case, then interventions that reduce the incidence of bacterial vaginosis might be valuable HIV prevention strategies.
What Did the Researchers Do and Find?
The researchers analyzed data collected from 2,236 heterosexual African couples enrolled in a clinical trial (the Partners in Prevention HSV/HIV Transmission Study) whose primary aim was to investigate whether suppression of herpes simplex virus infection could prevent HIV transmission. In all the couples, the woman was HIV-positive and the man was initially HIV-negative. The female partners were examined every three months for the presence of bacterial vaginosis and the male partners were tested regularly for HIV infection. The researchers also determined whether the men who became HIV-positive were infected with the same HIV strain as their partner to check that their infection had been acquired from this partner. The HIV incidence in men whose partners had bacterial vaginosis was 2.9 per 100 person-years (that is, 2.9 out of every 100 men became HIV-positive per year) whereas the HIV incidence in men whose partners had a normal vaginal flora was 0.76 per 100 person-years. After controlling for factors that might affect the risk of HIV transmission such as male circumcision and viral levels in female partner's blood, the researchers estimated that bacterial vaginosis was associated with a 3.17-fold increased risk of female-to-male HIV transmission in their study population.
What Do These Findings Mean?
These findings suggest that HIV-positive African women with bacterial vaginosis are more than three times as likely to transmit HIV to their male partners as those with a normal vaginal flora. It is possible that some unknown characteristic of the men in this study might have increased both their own risk of HIV infection and their partner's risk of bacterial vaginosis. Nevertheless, because bacterial vaginosis is so common in Africa (half of the women in this study had bacterial vaginosis at least once during follow-up) and because this condition is associated with both female HIV acquisition and transmission, these findings suggest that bacterial vaginosis could be responsible for a substantial proportion of new HIV infections in Africa. Normalization of vaginal flora in HIV-infected women by frequent presumptive treatment with antimicrobials (treatment with a curative dose of antibiotics without testing for bacterial vaginosis) or possibly by treatment with probiotics (live “good” bacteria) might, therefore, reduce female-to-male HIV transmission in sub-Saharan Africa.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001251.
Information is available from the US National Institute of Allergy and infectious diseases on all aspects of HIV infection and AIDS and on bacterial vaginosis
The US Centers for Disease Control and Prevention has information on all aspects of HIV/AIDS, including specific information about HIV/AIDS and women; it also has information on bacterial vaginosis (in English and Spanish)
NAM/aidsmap provides basic information about HIV/AIDS, and summaries of recent research findings on HIV care and treatment, and information on bacterial vaginosis and HIV transmission (in several languages)
Information is available from Avert, an international AIDS nonprofit group on many aspects of HIV/AIDS, including detailed information on HIV and AIDS prevention, on women, HIV and AIDS and on HIV/AIDS in Africa (in English and Spanish); personal stories of women living with HIV are available; the website Healthtalkonline also provides personal stories about living with HIV
More information about the Partners in Prevention HSV/HIV Transmission Study is available
doi:10.1371/journal.pmed.1001251
PMCID: PMC3383741  PMID: 22745608
9.  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
10.  Relationship between total bilirubin, endothelial function, inflammation and oxidative stress in HIV-infected adults on stable antiretroviral therapy 
HIV medicine  2012;13(10):609-616.
Objective
Enhanced inflammation is evident in HIV, even with virologic suppression. Outside HIV, studies show an independent association between higher total bilirubin and better endothelial function as well as lower prevalence of coronary heart disease possibly due to the anti-inflammatory and antioxidant effect of bilirubin.
Methods
A cross-sectional study was performed in HIV-1 infected adults on stable antiretroviral therapy (ART) to determine if a relationship exists between total bilirubin and endothelial function (flow mediated dilation (FMD) of the brachial artery), inflammation (interleukin-6 (IL-6), soluble tumor necrosis factor receptors, C-reactive protein, adhesion molecules), coagulation markers (fibrinogen and D-Dimer) and oxidative stress (F2-Isoprostanes). Endpoints were compared based on total bilirubin levels and atazanavir status using distributionally-appropriate, two-sample tests. Correlation coefficients were determined between total bilirubin and end points. Linear regression was used to model the relationship between total bilirubin (and atazanavir status) and FMD.
Results
98 adults were included. Total bilirubin was higher in atazanavir group (median (IQR) 1.8 (1.1–2.6) vs. 0.6 (0.4–1.4) mg/dL; p<0.01) as was insulin, HOMA-IR and fibrinogen. Total bilirubin was positively correlated with fibrinogen and was not correlated with other outcomes. After adjustment, neither total bilirubin nor atazanavir status was associated with FMD.
Conclusions
In virologically-suppressed, HIV-infected adults on stable ART, neither total bilirubin nor atazanavir use was associated with improved endothelial function as measured by FMD, inflammation or oxidative stress as measured by biomarkers.
doi:10.1111/j.1468-1293.2012.01026.x
PMCID: PMC3430799  PMID: 22624591
11.  HIV-1 Drug Resistance Emergence among Breastfeeding Infants Born to HIV-Infected Mothers during a Single-Arm Trial of Triple-Antiretroviral Prophylaxis for Prevention of Mother-To-Child Transmission: A Secondary Analysis 
PLoS Medicine  2011;8(3):e1000430.
Analysis of a substudy of the Kisumu breastfeeding trial by Clement Zeh and colleagues reveals the emergence of HIV drug resistance in HIV-positive infants born to HIV-infected mothers treated with antiretroviral drugs.
Background
Nevirapine and lamivudine given to mothers are transmitted to infants via breastfeeding in quantities sufficient to have biologic effects on the virus; this may lead to an increased risk of a breastfed infant's development of resistance to maternal antiretrovirals. The Kisumu Breastfeeding Study (KiBS), a single-arm open-label prevention of mother-to-child HIV transmission (PMTCT) trial, assessed the safety and efficacy of zidovudine, lamivudine, and either nevirapine or nelfinavir given to HIV-infected women from 34 wk gestation through 6 mo of breastfeeding. Here, we present findings from a KiBS trial secondary analysis that evaluated the emergence of maternal ARV-associated resistance among 32 HIV-infected breastfed infants.
Methods and Findings
All infants in the cohort were tested for HIV infection using DNA PCR at multiple study visits during the 24 mo of the study, and plasma RNA viral load for all HIV-PCR–positive infants was evaluated retrospectively. Specimens from mothers and infants with viral load >1,000 copies/ml were tested for HIV drug resistance mutations. Overall, 32 infants were HIV infected by 24 mo of age, and of this group, 24 (75%) infants were HIV infected by 6 mo of age. Of the 24 infants infected by 6 mo, nine were born to mothers on a nelfinavir-based regimen, whereas the remaining 15 were born to mothers on a nevirapine-based regimen. All infants were also given single-dose nevirapine within 48 hours of birth. We detected genotypic resistance mutations in none of eight infants who were HIV-PCR positive by 2 wk of age (specimens from six infants were not amplifiable), for 30% (6/20) at 6 wk, 63% (14/22) positive at 14 wk, and 67% (16/24) at 6 mo post partum. Among the 16 infants with resistance mutations by 6 mo post partum, the common mutations were M184V and K103N, conferring resistance to lamivudine and nevirapine, respectively. Genotypic resistance was detected among 9/9 (100%) and 7/15 (47%) infected infants whose mothers were on nelfinavir and nevirapine, respectively. No mutations were detected among the eight infants infected after the breastfeeding period (age 6 mo).
Conclusions
Emergence of HIV drug resistance mutations in HIV-infected infants occurred between 2 wk and 6 mo post partum, most likely because of exposure to maternal ARV drugs through breast milk. Our findings may impact the choice of regimen for ARV treatment of HIV-infected breastfeeding mothers and their infected infants.
Trial Registration
ClinicalTrials.gov NCT00146380
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Globally, more than 2 million children are infected with the human immunodeficiency virus (HIV) that causes acquired immunodeficiency syndrome (AIDS), and half a million children are newly infected every year. These infections are mainly the result of mother-to-child transmission (MTCT) of HIV during pregnancy, labor and delivery, or through breastfeeding. MTCT can be greatly reduced by treating HIV-positive mothers and their babies with antiretroviral drugs (ARVs). Without ARVs, up to half of babies born to HIV-positive mothers become infected with HIV. This rate of transmission falls to below 5% if a combination of three ARVs is given to the mother throughout pregnancy. Unfortunately, this triple-ARV therapy is too expensive for use in the resource-limited countries where most MTCT occurs. Instead, many such countries have introduced simpler, shorter ARV regimens such as a daily dose of zidovudine (a nucleoside reverse transcriptase inhibitor or NRTI) given to HIV-positive women during late pregnancy coupled with single-dose nevirapine (a non-nucleoside reverse transcriptase inhibitor or NNRTI) at the onset of labor, zidovudine and lamivudine (another NRTI) during labor and delivery, and single-dose nevirapine given to the baby at birth.
Why Was This Study Done?
More than 95% of HIV-exposed children are born in resource-limited settings where breastfeeding is the norm and is crucial for child survival even though it poses a risk of HIV transmission. Consequently, several recent studies have investigated whether MTCT can be further reduced by giving the mother ARVs while she is breastfeeding. In the Kisumu Breastfeeding Study (KiBS), for example, researchers assessed the effects of giving zidovudine, lamivudine, and either nevirapine or nelfinavir (a protease inhibitor) to HIV-infected women from 34 weeks of pregnancy through 6 months of breastfeeding. The results of KiBS indicate that this approach might be a safe, feasible way to reduce MTCT (see the accompanying paper by Thomas and colleagues). However, low amounts of nevirapine and lamivudine are transferred from mother to infant in breast milk and this exposure to ARVs could induce the development of resistance to ARVs among HIV-infected infants. In this KiBS substudy, the researchers investigate whether HIV drug resistance emerged in any of the HIV-positive infants in the parent study.
What Did the Researchers Do and Find?
In KiBS, 32 infants were HIV-positive at 24 months old; 24 were HIV-positive at 6 months old when their mothers stopped taking ARVs and when breastfeeding was supposed to stop. The researchers analyzed blood samples taken from these infants at various ages and from their mothers for the presence of HIV drug resistance mutations (DNA changes that make HIV resistant to killing by ARVs). They detected no resistance mutations in samples taken from 2-week old HIV-positive infants or from the infants who became infected after the age of 6 months. However, they found resistance mutations in a third and two-thirds of samples taken from 6-week and 6-month old HIV-positive infants, respectively. The commonest mutations conferred resistance to lamivudine and nevirapine. Moreover, resistance mutations were present in samples taken from all the HIV-positive infants whose mothers who had received nelfinavir but in only half those taken from infants whose mothers who had received nevirapine. Finally, most of the mothers of HIV-positive infants had no HIV drug resistance mutations, and only one mother-infant pair had an overlapping pattern of HIV drug resistance mutations.
What Do These Findings Mean?
These findings indicate that, in this KiBS substudy, the emergence of HIV drug resistance mutations in HIV-infected infants whose mothers were receiving ARVs occurred between 2 weeks and 6 months after birth. The pattern of mutations suggests that drug resistance most likely arose through exposure of the infants to low levels of ARVs in breast milk rather than through MTCT of drug-resistant virus. These findings need confirming but suggest that infants exposed to ARVs through breast milk—a situation that may become increasingly common given the reduction in MTCT seen in KiBS and other similar trials—should be carefully monitored for HIV infection. Providers should consider the mothers' regimen when choosing treatment for infants who are found to be HIV-infected despite maternal triple drug prophylaxis. Infants exposed to a maternal regimen with NNRTI drugs should receive first-line therapy with lopinavir/ritonavir, a protease inhibitor. The significance of the NRTI mutations such as M184V with regard to response to therapy needs further evaluation. The M184V mutation may result in hypersensitization to other NRTI drugs and delay or reverse zidovudine resistance. Given the limited availability of alternative drugs for infants in resource-limited settings, provision of the standard WHO-recommended first-line NRTI backbone, which includes 3TC, with enhanced monitoring of the infant to ensure virologic suppression, could be considered. Such an approach should reduce both illness and morbidity among infants who become HIV positive through breastfeeding.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/ 10.1371/journal.pmed.1000430.
The accompanying PLoS Medicine Research article by Thomas and colleagues describes the primary findings of the Kisumu Breastfeeding Study
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on HIV/AIDS
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on children, HIV, and AIDS and on preventing mother-to-child transmission of HIV (in English and Spanish)
UNICEF also has information about children and HIV and AIDS (in several languages)
The World Health organization has information on mother-to-child transmission of HIV (in several languages), and guidance on the use of ARVs for preventing MTCT
doi:10.1371/journal.pmed.1000430
PMCID: PMC3066134  PMID: 21468304
12.  Potential cardiovascular disease risk markers among HIV-infected women initiating antiretroviral treatment 
Background
Inflammation and hemostasis perturbation may be involved in vascular complications of HIV infection. We examined atherogenic biomarkers and subclinical atherosclerosis in HIV-infected adults before and after beginning highly-active antiretroviral therapy (HAART).
Methods
In the Women's Interagency HIV Study (WIHS), 127 HIV-infected women studied pre- and post-HAART were matched to HIV-uninfected controls. Six semi-annual measurements of soluble CD14, tumor necrosis factor (TNF)-alpha, soluble interleukin (IL)-2 receptor, IL-6, IL-10, monocyte chemoattractant protein (MCP)-1, D-dimer, and fibrinogen were obtained. Carotid artery intima-media thickness (CIMT) was measured by B-mode ultrasound.
Results
Relative to HIV-uninfected controls, HAART-naïve HIV-infected women had elevated levels of soluble CD14 (1945 vs 1662 ng/mL, Wilcoxon signed rank P<0.0001), TNF-alpha (6.3 vs 3.4 pg/mL, P<0.0001), soluble IL-2 receptor (1587 vs 949 pg/mL, P<0.0001), IL-10 (3.3 vs 1.9 pg/mL, P<0.0001), MCP-1 (190 vs 163 pg/mL, P<0.0001) and D-dimer (0.43 vs 0.31 µg/mL, P<0.01). Elevated biomarker levels declined after HAART. While most biomarkers normalized to HIV-uninfected levels, in women on effective HAART, TNF-alpha levels remained elevated compared to HIV-uninfected women (+0.8 pg/mL, P=0.0002). Higher post-HAART levels of soluble IL-2 receptor (P=0.02), IL-6 (P=0.05), and D-dimer (P=0.03) were associated with increased CIMT.
Conclusions
Untreated HIV infection is associated with abnormal hemostasis (e.g., D-dimer), and pro-atherogenic (e.g., TNF-alpha) and anti-atherogenic (e.g., IL-10) inflammatory markers. HAART reduces most inflammatory mediators to HIV-uninfected levels. Increased inflammation and hemostasis are associated with subclinical atherosclerosis in recently treated women. These findings have potential implications for long-term risk of cardiovascular disease in HIV-infected patients, even with effective therapy.
doi:10.1097/QAI.0b013e31825b03be
PMCID: PMC3400505  PMID: 22592585
antiretroviral therapy; cardiovascular diseases; cytokines; hemostasis; HIV; inflammation
13.  Early and Late Direct Costs in a Southern African Antiretroviral Treatment Programme: A Retrospective Cohort Analysis 
PLoS Medicine  2009;6(12):e1000189.
Gary Maartens and colleagues describe the direct heath care costs and identify the drivers of cost over time in an HIV managed care program in Southern Africa.
Background
There is a paucity of data on the health care costs of antiretroviral therapy (ART) programmes in Africa. Our objectives were to describe the direct heath care costs and establish the cost drivers over time in an HIV managed care programme in Southern Africa.
Methods/Findings
We analysed the direct costs of treating HIV-infected adults enrolled in the managed care programme from 3 years before starting non-nucleoside reverse transcriptase inhibitor-based ART up to 5 years afterwards. The CD4 cell count criterion for starting ART was <350 cells/µl. We explored associations between variables and mean total costs over time using a generalised linear model with a log-link function and a gamma distribution. Our cohort consisted of 10,735 patients (59.4% women) with 594,497 mo of follow up data (50.9% of months on ART). Median baseline CD4+ cell count and viral load were 125 cells/µl and 5.16 log10 copies/ml respectively. There was a peak in costs in the period around ART initiation (from 4 mo before until 4 mo after starting ART) driven largely by hospitalisation, following which costs plateaued for 5 years. The variables associated with changes in mean total costs varied with time. Key early associations with higher costs were low baseline CD4+ cell count, high baseline HIV viral load, and shorter duration in HIV care prior to starting ART; whilst later associations with higher costs were lower ART adherence, switching to protease inhibitor-based ART, and starting ART at an older age.
Conclusions
Drivers of mean total costs changed considerably over time. Starting ART at higher CD4 counts or longer pre-ART care should reduce early costs. Monitoring ART adherence and interventions to improve it should reduce later costs. Cost models of ART should take into account these time-dependent cost drivers, and include costs before starting ART.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
About 30 million people (22 million people in sub-Saharan Africa alone) are infected with the human immunodeficiency virus (HIV), the cause of acquired immunodeficiency syndrome (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, on average HIV-positive people died within 10 years of infection. Then, in 1996, highly active antiretroviral therapy (ART; combinations of powerful antiretroviral drugs) was developed. For people living in affluent, developed countries HIV/AIDS became a chronic, treatable condition, but for the millions of HIV-infected people living in low- and middle-income countries, effective treatment was unavailable and HIV/AIDS remained a fatal illness. 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. By the end of 2008, of the 9.5 million people in need of ART in low- and middle-income countries, more than 4 million people were receiving treatment.
Why Was This Study Done?
Good progress is being made towards achieving universal access to ART, partly because the cost of antiretroviral drugs has plummeted in developing countries. But the provision of antiretroviral drugs is not the only direct cost associated with ART. General practitioner, specialist, and maternity-related care for patients receiving ART, hospital accommodation when necessary, and the investigations that are needed to monitor the progress of HIV infection such as CD4 cell counts and viral load measurements all incur considerable costs. To use their limited resources effectively, public-health officials in developing countries need to know as much as possible about the direct costs of HIV health care but few studies have investigated these costs, particularly those incurred before an individual starts taking ART. In this study, the researchers explore health care costs in a South African private-sector HIV/AIDS program and examine the variables that drive the costs of HIV health care around the time of ART initiation and during later phases of ART.
What Did the Researchers Do and Find?
The researchers analyzed the direct costs of treating more than 100,000 HIV-infected adults enrolled in a private HIV care program in South Africa from 3 years before they started ART until up to 5 years after ART initiation; within this program, individuals began to receive ART when their CD4 cell count fell below 350 cells/µl of blood. The researchers found a peak in direct health costs from 4 months before to 4 months after starting ART (the “peri-ART” period), which was driven mainly by hospital costs. After the peri-ART period, costs dropped (although not to the levels seen before this period) and stabilized at an intermediate level for the next 5 years. Detailed statistical analyses suggest that the key variables associated with higher costs in the peri-ART period were a low baseline CD4 cell count, a high baseline HIV viral load, and a shorter time in HIV care before ART initiation. The key variable associated with higher costs later in ART was lower adherence to the drug therapy. That is, costs were higher among patients who did not take their antiretroviral drugs regularly.
What Do These Findings Mean?
This study involved patients enrolled in a private health care program in which the criteria for initiating ART differed somewhat from those recommended by the World Health Organization for ART initiation in resource-limited settings. Thus, the absolute mean total costs calculated by the researchers are unlikely to be generalizable to public HIV care systems in South Africa and in other resource-poor settings. However, the finding that the drivers of mean total costs change considerably over time may be generalizable and provides some useful information for public-health planners that can now be tested in other, more resource-limited patient populations. In particular, the findings of this study suggest that the high early costs of ART programs could be reduced by starting ART at higher CD4 cell counts or by providing longer pre-ART care. In addition, the findings suggest that monitoring ART adherence and introducing interventions to improve ART adherence could reduce the later direct costs 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.1000189.
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 and AIDS in Africa, and on universal access to AIDS treatment (in English and Spanish)
The World Health Organization provides information about universal access to AIDS treatment, including the September 2009 progress report (in English and French)
The US Centers for Disease Control and Prevention also provides information on global efforts to deal with the HIV/AIDS epidemic
doi:10.1371/journal.pmed.1000189
PMCID: PMC2777319  PMID: 19956658
14.  The Effect of Raltegravir Intensification on Low-level Residual Viremia in HIV-Infected Patients on Antiretroviral Therapy: A Randomized Controlled Trial 
PLoS Medicine  2010;7(8):e1000321.
In a double-blind trial, Rajesh Gandhi and colleagues detect no significant reduction in viral load after people with low-level HIV viremia added an integrase inhibitor to their treatment regimen.
Background
Most HIV-1-infected patients on effective antiretroviral therapy (ART) with plasma HIV-1 RNA levels below the detection limits of commercial assays have residual viremia measurable by more sensitive methods. We assessed whether adding raltegravir lowered the level of residual viremia in such patients.
Methods and Findings
Patients receiving ART who had plasma HIV-1 RNA levels below 50 copies/mL but detectable viremia by single copy assay (SCA) were randomized to add either raltegravir or placebo to their ART regimen for 12 weeks; patients then crossed-over to the other therapy for an additional 12 weeks while continuing pre-study ART. The primary endpoint was the plasma HIV-1 RNA by SCA averaged between weeks 10 and 12 (10/12) compared between treatment groups. Fifty-three patients were enrolled. The median screening HIV-1 RNA was 1.7 copies/mL. The HIV-1 RNA level at weeks 10/12 did not differ significantly between the raltegravir-intensified (n = 25) and the placebo (n = 24) groups (median 1.2 versus 1.7 copies/mL, p = 0.55, Wilcoxon rank sum test), nor did the change in HIV-1 RNA level from baseline to week 10/12 (median −0.2 and −0.1 copies/mL, p = 0.71, Wilcoxon rank sum test). There was also no significant change in HIV-1 RNA level from weeks 10/12 to weeks 22/24 after patients crossed-over. There was a greater CD4 cell count increase from baseline to week 12 in the raltegravir-intensified group compared with the placebo group (+42 versus −44 cells/mm3, p = 0.082, Wilcoxon rank sum test), which reversed after the cross-over. This CD4 cell count change was not associated with an effect of raltegravir intensification on markers of CD4 or CD8 cell activation in blood.
Conclusion
In this randomized, double-blind cross-over study, 12 weeks of raltegravir intensification did not demonstrably reduce low-level plasma viremia in patients on currently recommended ART. This finding suggests that residual viremia does not arise from ongoing cycles of HIV-1 replication and infection of new cells. New therapeutic strategies to eliminate reservoirs that produce residual viremia will be required to eradicate HIV-1 infection.
Trial Registration
ClinicalTrials.gov NCT00515827
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Acquired immunodeficiency syndrome (AIDS) has killed about 25 million people since 1981 and more than 30 million people are now infected with the human immunodeficiency virus (HIV), which causes AIDS. HIV is a retrovirus—its genetic blueprint is made of ribonucleic acid (RNA). HIV infects human immune system cells and destroys them, leaving infected individuals susceptible to other infections. Early during the AIDS epidemic, most HIV-positive people died within ten years of infection. Then, in 1996, effective antiretroviral therapy (ART) was developed. ART consists of combinations of drugs that prevent viral replication by inhibiting essential viral enzymes such as reverse transcriptase (the enzyme that makes a DNA copy of the viral RNA; a viral enzyme called integrase inserts this DNA copy into the host cell DNA where it remains dormant until the host cell is activated) and protease (an enzyme needed for the production of new viral particles, which are released into the blood stream). Now, in industrialized countries, the life expectancy of HIV-infected patients treated with ART is similar to that of people with diabetes and other chronic conditions.
Why Was This Study Done?
Although ART can reduce the number of viral RNA copies in the plasma (the liquid portion of blood) of HIV-positive patients to less than 50 copies/mL (the limit of detection of commercial assays), it is does not eradicate HIV. When very sensitive assays are used to detect viral RNA (for example, the “single copy assay” or SCA), most patients on ART have one copy or more of HIV RNA per mL of plasma. The origin of this low-level residual viremia (virus in the blood) is controversial. Residual viremia could arise from ongoing cycles of viral replication, in which case intensification of ART should reduce it. Alternatively, residual viremia could be due to HIV release from stable reservoirs such as latently infected resting immune system cells, in which case intensification of ART should have no effect on residual viremia. In this randomized, controlled trial (a study in which randomly selected groups of patients are given different treatments and the effects of these treatments compared), the researchers assess whether the addition of raltegravir (a drug that inhibits HIV integrase) to standard ART has any effect on residual viremia.
What Did the Researchers Do and Find?
The researchers enrolled 53 HIV-positive patients who had been receiving ART containing several reverse transcriptase inhibitors and, in some cases, a protease inhibitor for at least 12 months and who had a plasma HIV RNA level below 50 copies/mL but detectable viremia by SCA. The patients were randomly assigned to receive either raltegravir or a dummy drug (placebo) in addition to their normal ART for 12 weeks. They were then crossed-over (swapped) to the other therapy for a further 12 weeks. At baseline, the trial participants had an average plasma HIV RNA level of 1.7 copies/mL. The HIV RNA level at weeks 10/12 (the average of SCA results at 10 and 12 weeks) was similar in the raltegravir group and in the placebo group and did not differ significantly from this baseline level. There was also no significant change in plasma HIV RNA levels from weeks 10/12 to weeks 22/24 after the patients crossed-over between treatment groups.
What Do These Findings Mean?
In this randomized, cross-over study, raltegravir intensification of ART for 12 weeks did not demonstrably reduce low-level residual viremia in HIV-positive patients receiving standard ART. It is possible that 12 weeks is too short a time to see an effect of raltegravir on residual viremia. Furthermore, although this is one of the biggest trials of this type done to date, it might be that insufficient patients were included in the trial to detect a subtle effect of raltegravir on residual viremia. Nevertheless, these findings argue against the hypothesis that residual viremia arises from ongoing cycles of viral replication and the infection of new cells. Instead, they suggest that residual viremia might be due to the release of HIV from stable reservoirs. If so, new therapeutic strategies designed to eliminate these reservoirs of latently infected cells will be required to cure HIV infection.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000321.
Information is available from the US National Institute of Allergy and infectious diseases on HIV infection and AIDS, and on the treatment of HIV
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including information on antiretroviral therapies
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including the treatment of HIV and AIDS (in English and Spanish)
MedlinePlus has links to further resources on AIDS and on AIDS medicines (in English and Spanish)
doi:10.1371/journal.pmed.1000321
PMCID: PMC2919424  PMID: 20711481
15.  Minority HIV-1 Drug Resistance Mutations Are Present in Antiretroviral Treatment–Naïve Populations and Associate with Reduced Treatment Efficacy 
PLoS Medicine  2008;5(7):e158.
Background
Transmitted HIV-1 drug resistance can compromise initial antiretroviral therapy (ART); therefore, its detection is important for patient management. The absence of drug-associated selection pressure in treatment-naïve persons can cause drug-resistant viruses to decline to levels undetectable by conventional bulk sequencing (minority drug-resistant variants). We used sensitive and simple tests to investigate evidence of transmitted drug resistance in antiretroviral drug-naïve persons and assess the clinical implications of minority drug-resistant variants.
Methods and Findings
We performed a cross-sectional analysis of transmitted HIV-1 drug resistance and a case-control study of the impact of minority drug resistance on treatment response. For the cross-sectional analysis, we examined viral RNA from newly diagnosed ART-naïve persons in the US and Canada who had no detectable (wild type, n = 205) or one or more resistance-related mutations (n = 303) by conventional sequencing. Eight validated real-time PCR-based assays were used to test for minority drug resistance mutations (protease L90M and reverse transcriptase M41L, K70R, K103N, Y181C, M184V, and T215F/Y) above naturally occurring frequencies. The sensitive real-time PCR testing identified one to three minority drug resistance mutation(s) in 34/205 (17%) newly diagnosed persons who had wild-type virus by conventional genotyping; four (2%) individuals had mutations associated with resistance to two drug classes. Among 30/303 (10%) samples with bulk genotype resistance mutations we found at least one minority variant with a different drug resistance mutation. For the case-control study, we assessed the impact of three treatment-relevant drug resistance mutations at baseline from a separate group of 316 previously ART-naïve persons with no evidence of drug resistance on bulk genotype testing who were placed on efavirenz-based regimens. We found that 7/95 (7%) persons who experienced virologic failure had minority drug resistance mutations at baseline; however, minority resistance was found in only 2/221 (0.9%) treatment successes (Fisher exact test, p = 0.0038).
Conclusions
These data suggest that a considerable proportion of transmitted HIV-1 drug resistance is undetected by conventional genotyping and that minority mutations can have clinical consequences. With no treatment history to help guide therapies for drug-naïve persons, the findings suggest an important role for sensitive baseline drug resistance testing.
Using real-time PCR to detect HIV resistance mutations present at low levels, Jeffrey Johnson and colleagues investigate prevalence and clinical implications of minority transmitted mutations.
Editors' Summary
Background
Since the mid-1990s, several powerful antiretroviral drug combinations have been developed that have greatly improved the prognosis of HIV infection. All antiretroviral therapy (ART) regimens combine drugs that act against HIV in different ways (so-called different drug classes). Multiple drugs are necessary because HIV continually accumulates random changes (mutations) in its genetic material (genome). Some of these mutations make HIV resistant to individual antiretroviral drugs, so a mixture of drugs is needed to keep the virus in check. However, the efficacy of ART (which itself selects for drug-resistant variants by giving them a growth advantage over drug-sensitive variants) is substantially reduced when these variants account for more than about 20% of the viruses in an infected person. This level of variant virus can be detected in blood samples with a technique called bulk sequencing. In North America and Europe, where ART has been widely used for many years, around 20% of HIV-infected people who have taken ART themselves develop this level of drug-resistant virus, which can be transmitted by the same routes as nonresistant HIV (typically unprotected sexual intercourse or needle sharing). In such cases, the person acquiring drug-resistant HIV may experience treatment failure when drugs later fail to work against the resistant virus. In these countries, therefore, resistance testing by bulk sequencing is done routinely before ART is initiated to decide which antiviral drugs are likely to be effective.
Why Was This Study Done?
Several years usually elapse between the time a person becomes infected with HIV and the time he or she starts ART. During this time, the absence of selection pressure from antiviral drugs means that transmitted drug-resistant variants tend to decline to levels undetectable by bulk sequencing. These “minority drug-resistant variants” can be detected using other more sensitive tests but it is not known what proportion of HIV-infected people who have never taken ART carry minority drug-resistant variants (the “prevalence” of these variants). It is also unknown whether the presence of minority drug-resistant variants reduces the success of ART. In this paper, the researchers first report a “cross-sectional” study in North America using a sensitive assay to determine the prevalence of minority drug-resistant viruses among HIV-infected people who had never received ART. They then investigate whether minority drug-resistant variants have any impact on the effectiveness of ART in a “case-control” study.
What Did the Researchers Do and Find?
In their cross-sectional study, the researchers used a highly sensitive test for detecting mutations (called a real-time PCR-based assay) to look for low levels of viruses carrying any of eight major drug-resistance mutations in people with newly diagnosed HIV infection who reported no prior treatment with ART. Seventeen percent of the people who had only wild-type (nonmutated) virus by bulk sequencing (205 participants) were found, in fact, to carry low levels of virus variants with 1–3 drug-resistance mutations; 2% of them carried viruses resistant to two different drug classes (called multi-drug resistance). Among the people with resistance mutations detected by bulk sequencing (303 participants), 10% had at least one additional minority drug-resistant variant, often a viral variant that was resistant to a drug class different from that detected by bulk sequencing. In the case-control study, the researchers used their sensitive assays to measure the levels of viruses containing any of the three most common drug resistance mutations likely to affect viral responses to the antiretroviral drugs efavirenz and lamivudine in 316 people just before they started their first HIV treatment, which included these drugs. Of people for whom ART failed, 7% were infected with minority drug-resistant virus variants at baseline compared with only 0.9% of people for whom ART worked; this difference was statistically significant.
What Do These Findings Mean?
The findings of the cross-sectional study indicate that conventional bulk sequencing fails to detect a large proportion of transmitted HIV drug resistance and suggest that the transmission of drug-resistant variants from infectious ART-experienced people to ART-naïve individuals might not be uncommon. The findings of the case-control study suggest that the minority drug-resistant HIV variants may have clinical consequences. That is, the presence of such variants in individuals who have not previously taken ART may reduce the efficacy of some ART regimens. However, the number of participants meeting the criteria for analysis in the cross-sectional study was limited, and the association between minority resistance and treatment failure may have been influenced by other factors. Taken together, these findings suggest that, to ensure that first-line ART is as effective as possible, greater efforts should be made to prevent HIV transmission, whether from ART-experienced or ART-naive people. However, because data on minority drug-resistant virus are limited, more studies— particularly with recent populations—are needed before testing for these variants can be considered appropriate in the clinical management of newly diagnosed HIV infection.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050158.
This study is further discussed in a PLoS Medicine Perspective by Steven G. Deeks
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 links to fact sheets (in English, French, and Spanish) about antiretrovirals and information on genetic testing for HIV drug resistance
NAM, a UK registered charity, provides information about all aspects of HIVand AIDS, including fact sheets on types of HIV drug, drug resistance, and resistance tests (in English, Spanish, French, Portuguese, and Russian)
The US Centers for Disease Control and Prevention provides information on HIV/AIDS and on treatment (in English and Spanish)
doi:10.1371/journal.pmed.0050158
PMCID: PMC2488194  PMID: 18666824
16.  Adherence to Antiretroviral Prophylaxis for HIV Prevention: A Substudy Cohort within a Clinical Trial of Serodiscordant Couples in East Africa 
PLoS Medicine  2013;10(9):e1001511.
Jessica Haberer and colleagues investigate the association between high adherence to antiretroviral pre-exposure prophylaxis and HIV transmission in a substudy of serodiscordant couples participating in a clinical trial.
Please see later in the article for the Editors' Summary
Background
Randomized clinical trials of oral antiretroviral pre-exposure prophylaxis (PrEP) for HIV prevention have widely divergent efficacy estimates, ranging from 0% to 75%. These discrepancies are likely due to differences in adherence. To our knowledge, no studies to date have examined the impact of improving adherence through monitoring and/or intervention, which may increase PrEP efficacy, or reported on objective behavioral measures of adherence, which can inform PrEP effectiveness and implementation.
Methods and Findings
Within the Partners PrEP Study (a randomized placebo-controlled trial of oral tenofovir and emtricitabine/tenofovir among HIV-uninfected members of serodiscordant couples in Kenya and Uganda), we collected objective measures of PrEP adherence using unannounced home-based pill counts and electronic pill bottle monitoring. Participants received individual and couples-based adherence counseling at PrEP initiation and throughout the study; counseling was intensified if unannounced pill count adherence fell to <80%. Participants were followed monthly to provide study medication, adherence counseling, and HIV testing. A total of 1,147 HIV-uninfected participants were enrolled: 53% were male, median age was 34 years, and median partnership duration was 8.5 years. Fourteen HIV infections occurred among adherence study participants—all of whom were assigned to placebo (PrEP efficacy = 100%, 95% confidence interval 83.7%–100%, p<0.001). Median adherence was 99.1% (interquartile range [IQR] 96.9%–100%) by unannounced pill counts and 97.2% (90.6%–100%) by electronic monitoring over 807 person-years. Report of no sex or sex with another person besides the study partner, younger age, and heavy alcohol use were associated with <80% adherence; the first 6 months of PrEP use and polygamous marriage were associated with >80% adherence. Study limitations include potential shortcomings of the adherence measures and use of a convenience sample within the substudy cohort.
Conclusions
The high PrEP adherence achieved in the setting of active adherence monitoring and counseling support was associated with a high degree of protection from HIV acquisition by the HIV-uninfected partner in heterosexual serodiscordant couples. Low PrEP adherence was associated with sexual behavior, alcohol use, younger age, and length of PrEP use.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Every year, about 2.5 million people (mostly living in sub-Saharan Africa) become infected with HIV, the virus that causes AIDS. HIV, which is usually transmitted through unprotected sex with an HIV-infected partner, destroys immune system cells, leaving infected individuals susceptible to other infections. There is no cure for AIDS, although antiretroviral drugs can hold HIV in check, and there is no vaccine against HIV infection. Individuals can reduce their risk of HIV infection by abstaining from sex, by having only one or a few low risk sexual partners, and by always using a condom. In addition, antiretroviral drugs can potentially be used in two ways to reduce HIV transmission. First, these drugs could be given to HIV-positive individuals to reduce their infectiousness. Second, antiretroviral drugs could be given to HIV-uninfected people to reduce acquisition of the virus. This approach—pre-exposure prophylaxis (PrEP)—has provided varying levels of protection against HIV infection in randomized controlled trials (RCT; studies that monitor the outcomes of groups of patients randomly assigned to receive different test drugs or a placebo/dummy drug).
Why Was This Study Done?
One hypothesis for the varying efficacy of PrEP in RCTs is differential adherence—differences in whether trial participants took the antiretroviral drugs correctly. Antiretroviral drugs only control HIV infections effectively when they are taken regularly and adherence to antiretroviral PrEP is probably also important for HIV prevention. Here, the researchers investigate adherence to antiretroviral prophylaxis in a substudy within the Partners PrEP Study, a placebo-controlled RCT of oral antiretroviral drugs among nearly 5,000 HIV-uninfected members of serodiscordant couples in East Africa. In serodiscordant couples, only one partner is HIV-positive; 20% of couples in Africa who know their HIV status are serodiscordant. In the Partner PrEP Study, the efficacy of HIV protection with oral antiretroviral drugs was 67%–75%.
What Did the Researchers Do and Find?
The researchers selected a “convenience” sample—a sample is taken non-randomly from a population that is close at hand—of 1,147 HIV-uninfected partners enrolled in Uganda. They used unannounced home-based pill counts (an approach that reduced the chance of participants dumping unused pills to appear more adherent than they actually were) and electronic pill bottle monitoring (a microchip in the medication bottle cap recorded whenever the bottle was opened) to measure PrEP adherence in this cohort. All the participants received adherence counseling at PrEP initiation and throughout the study; counseling was intensified if unannounced pill count adherence fell below 80%. Fourteen participants, all of whom had been assigned to placebo, became HIV-positive during the adherence substudy. The average adherence to PrEP was 99.1% and 97.2% as measured by unannounced pill counts and by electronic monitoring, respectively. About 7% and 26% of participants had less than 80% adherence as measured by unannounced pill count and electronic monitoring, respectively, during at least one 3-month period of the substudy. Greater than 80% adherence was associated with the first 6 months of PrEP use and polygamous marriage. Adherence less than 80% was associated with report of no sex or sex with another person besides the study partner, younger age, and heavy alcohol use. Finally, the adherence intervention (intensified counseling) was well received and in the first unannounced pill count after the intervention, adherence increased to above 80% in 92% of participants.
What Do These Findings Mean?
These findings indicate that the high level of PrEP adherence achieved in the setting of active adherence monitoring and counseling support was associated with a high level of protection from HIV acquisition by the HIV-uninfected partner in heterosexual serodiscordant couples. The findings also suggest that low PrEP adherence is associated with sexual behavior, alcohol use, younger age, and length of PrEP use. Several aspects of the study design may limit the accuracy of these findings. For example, although the adherence measures used here are probably more accurate than participant reports of missed doses and clinic-based pill counts (adherence measures that are often used in RCTs), they are not perfect. Nevertheless, these findings provide further support for the ability of PrEP to prevent HIV acquisition when taken regularly; they suggest that adherence interventions in the implementation setting should address sexual behavior, risk perception, and heavy alcohol use; and they provide data to guide ethical decisions about resource allocation for prevention and treatment of HIV infection.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001511.
The 2012 UNAIDS World AIDS Day Report provides up-to-date information about the AIDS epidemic and efforts to halt it
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 information on HIV transmission and prevention and on PrEP
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV and AIDS in Uganda, on HIV prevention, and on PrEP (in English and Spanish)
PrEP Watch provides detailed information about PrEP and links to other resources; it includes personal stories from people who have chosen to use PrEP
More information about the Partners PrEP Study is available
Personal stories about living with HIV/AIDS are available through Avert, through Nam/aidsmap, and through the charity website Healthtalkonline
doi:10.1371/journal.pmed.1001511
PMCID: PMC3769210  PMID: 24058300
17.  Emergence of Drug Resistance Is Associated with an Increased Risk of Death among Patients First Starting HAART 
PLoS Medicine  2006;3(9):e356.
Background
The impact of the emergence of drug-resistance mutations on mortality is not well characterized in antiretroviral-naïve patients first starting highly active antiretroviral therapy (HAART). Patients may be able to sustain immunologic function with resistant virus, and there is limited evidence that reduced sensitivity to antiretrovirals leads to rapid disease progression or death. We undertook the present analysis to characterize the determinants of mortality in a prospective cohort study with a median of nearly 5 y of follow-up. The objective of this study was to determine the impact of the emergence of drug-resistance mutations on survival among persons initiating HAART.
Methods and Findings
Participants were antiretroviral therapy naïve at entry and initiated triple combination antiretroviral therapy between August 1, 1996, and September 30, 1999. Marginal structural modeling was used to address potential confounding between time-dependent variables in the Cox proportional hazard regression models. In this analysis resistance to any class of drug was considered as a binary time-dependent exposure to the risk of death, controlling for the effect of other time-dependent confounders. We also considered each separate class of mutation as a binary time-dependent exposure, while controlling for the presence/absence of other mutations. A total of 207 deaths were identified among 1,138 participants over the follow-up period, with an all cause mortality rate of 18.2%. Among the 679 patients with HIV-drug-resistance genotyping done before initiating HAART, HIV-drug resistance to any class was observed in 53 (7.8%) of the patients. During follow-up, HIV-drug resistance to any class was observed in 302 (26.5%) participants. Emergence of any resistance was associated with mortality (hazard ratio: 1.75 [95% confidence interval: 1.27, 2.43]). When we considered each class of resistance separately, persons who exhibited resistance to non-nucleoside reverse transcriptase inhibitors had the highest risk: mortality rates were 3.02 times higher (95% confidence interval: 1.99, 4.57) for these patients than for those who did not exhibit this type of resistance.
Conclusions
We demonstrated that emergence of resistance to non-nucleoside reverse transcriptase inhibitors was associated with a greater risk of subsequent death than was emergence of protease inhibitor resistance. Future research is needed to identify the particular subpopulations of men and women at greatest risk and to elucidate the impact of resistance over a longer follow-up period.
Emergence of resistance to both non-nucleoside reverse transcriptase inhibitors and protease inhibitors was associated with a higher risk of subsequent death, but the risk was greater in patients with NNRTI-resistant HIV.
Editors' Summary
Background.
In the 1980s, infection with the human immunodeficiency virus (HIV) was effectively a death sentence. HIV causes AIDS (acquired immunodeficiency syndrome) by replicating inside immune system cells and destroying them, which leaves infected individuals unable to fight off other viruses and bacteria. The first antiretroviral drugs were developed quickly, but it soon became clear that single antiretrovirals only transiently suppress HIV infection. HIV mutates (accumulates random changes to its genetic material) very rapidly and, although most of these changes (or mutations) are bad for the virus, by chance some make it drug resistant. Highly active antiretroviral therapy (HAART), which was introduced in the mid-1990s, combines three or four antiretroviral drugs that act at different stages of the viral life cycle. For example, they inhibit the reverse transcriptase that the virus uses to replicate its genetic material, or the protease that is necessary to assemble new viruses. With HAART, the replication of any virus that develops resistance to one drug is inhibited by the other drugs in the mix. As a consequence, for many individuals with access to HAART, AIDS has become a chronic rather than a fatal disease. However, being on HAART requires patients to take several pills a day at specific times. In addition, the drugs in the HAART regimens often have side effects.
Why Was This Study Done?
Drug resistance still develops even with HAART, often because patients don't stick to the complicated regimens. The detection of resistance to one drug is usually the prompt to change a patient's drug regimen to head off possible treatment failure. Although most patients treated with HAART live for many years, some still die from AIDS. We don't know much about how the emergence of drug-resistance mutations affects mortality in patients who are starting antiretroviral therapy for the first time. In this study, the researchers looked at how the emergence of drug resistance affected survival in a group of HIV/AIDS patients in British Columbia, Canada. Here, everyone with HIV/AIDS has access to free medical attention, HAART, and laboratory monitoring, and full details of all HAART recipients are entered into a central reporting system.
What Did the Researchers Do and Find?
The researchers enrolled people who started antiretroviral therapy for the first time between August 1996 and September 1999 into the HAART Observational Medical Evaluation and Research (HOMER) cohort. They then excluded anyone who was infected with already drug-resistant HIV strains (based on the presence of drug-resistance mutations in viruses isolated from the patients) at the start of therapy. The remaining 1,138 patients were followed for an average of five years. All the patients received either two nucleoside reverse transcriptase inhibitors and a protease inhibitor, or two nucleoside and one non-nucleoside reverse transcriptase inhibitor (NNRTI). Nearly a fifth of the study participants died during the follow-up period. Most of these patients actually had drug-sensitive viruses, possibly because they had neglected taking their drugs to such an extent that there had been insufficient drug exposure to select for drug-resistant viruses. In a quarter of the patients, however, HIV strains resistant to one or more antiretroviral drugs emerged during the study (again judged by looking for mutations). Detailed statistical analyses indicated that the emergence of any drug resistance nearly doubled the risk of patients dying, and that people carrying viruses resistant to NNRTIs were three times as likely to die as those without resistance to this class of antiretroviral drug.
What Do These Findings Mean?
These results provide new information about the emergence of drug-resistant HIV during HAART and possible effects on the long-term survival of patients. In particular, they suggest that clinicians should watch carefully for the emergence of resistance to NNRTIs in their patients. Because this type of resistance is often due to poor adherence to drug regimens, these results also suggest that increased efforts should be made to ensure that patients comply with the prescribed HAART regimens, especially those whose antiretroviral therapy includes NNRTIs. As with all studies in which a group of individuals who share a common characteristic are studied over time, it is possible that some other, unmeasured difference between the patients who died and those who didn't—rather than emerging drug resistance—is responsible for the observed differences in survival. Additional studies are needed to confirm the findings here, and to investigate whether specific subpopulations of patients are at particular risk of developing drug resistance and/or dying during HAART.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0030356.
US National Institute of Allergy and Infectious Diseases fact sheet on HIV infection and AIDS
US Department of Health and Human Services information on AIDS, including details of approved drugs for the treatment of HIV infection
US Centers for Disease Control and Prevention information on HIV/AIDS
Aidsmap, information on HIV and AIDS provided by the charity NAM, which includes details on antiretroviral drugs
doi:10.1371/journal.pmed.0030356
PMCID: PMC1569883  PMID: 16984218
18.  Effectiveness and Cost Effectiveness of Expanding Harm Reduction and Antiretroviral Therapy in a Mixed HIV Epidemic: A Modeling Analysis for Ukraine 
PLoS Medicine  2011;8(3):e1000423.
A cost-effectiveness study by Sabina Alistar and colleagues evaluates the effectiveness and cost effectiveness of different levels of investment in methadone, ART, or both, in the mixed HIV epidemic in Ukraine.
Background
Injection drug use (IDU) and heterosexual virus transmission both contribute to the growing mixed HIV epidemics in Eastern Europe and Central Asia. In Ukraine—chosen in this study as a representative country—IDU-related risk behaviors cause half of new infections, but few injection drug users (IDUs) receive methadone substitution therapy. Only 10% of eligible individuals receive antiretroviral therapy (ART). The appropriate resource allocation between these programs has not been studied. We estimated the effectiveness and cost-effectiveness of strategies for expanding methadone substitution therapy programs and ART in mixed HIV epidemics, using Ukraine as a case study.
Methods and Findings
We developed a dynamic compartmental model of the HIV epidemic in a population of non-IDUs, IDUs using opiates, and IDUs on methadone substitution therapy, stratified by HIV status, and populated it with data from the Ukraine. We considered interventions expanding methadone substitution therapy, increasing access to ART, or both. We measured health care costs, quality-adjusted life years (QALYs), HIV prevalence, infections averted, and incremental cost-effectiveness. Without incremental interventions, HIV prevalence reached 67.2% (IDUs) and 0.88% (non-IDUs) after 20 years. Offering methadone substitution therapy to 25% of IDUs reduced prevalence most effectively (to 53.1% IDUs, 0.80% non-IDUs), and was most cost-effective, averting 4,700 infections and adding 76,000 QALYs compared with no intervention at US$530/QALY gained. Expanding both ART (80% coverage of those eligible for ART according to WHO criteria) and methadone substitution therapy (25% coverage) was the next most cost-effective strategy, adding 105,000 QALYs at US$1,120/QALY gained versus the methadone substitution therapy-only strategy and averting 8,300 infections versus no intervention. Expanding only ART (80% coverage) added 38,000 QALYs at US$2,240/QALY gained versus the methadone substitution therapy-only strategy, and averted 4,080 infections versus no intervention. Offering ART to 80% of non-IDUs eligible for treatment by WHO criteria, but only 10% of IDUs, averted only 1,800 infections versus no intervention and was not cost effective.
Conclusions
Methadone substitution therapy is a highly cost-effective option for the growing mixed HIV epidemic in Ukraine. A strategy that expands both methadone substitution therapy and ART to high levels is the most effective intervention, and is very cost effective by WHO criteria. When expanding ART, access to methadone substitution therapy provides additional benefit in infections averted. Our findings are potentially relevant to other settings with mixed HIV epidemics.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
HIV epidemics in Eastern Europe and Central Asia are mainly driven by increasing use of injection drugs combined with heterosexual transmission. In the Ukraine, in 2007, there were 82,000 officially registered people living with HIV—three times the number registered in 1999—and an estimated 395,000 HIV infected adults. The epidemic in Ukraine, like other countries in the region, is concentrated in at-risk populations, particularly people who inject drugs: in 2007, an estimated 390,000 Ukrainians were injecting drugs, an increase in drug use over the previous decade, not only in Ukraine, but in other former USSR states, owing to the easy availability of precursors for injection drugs in a climate of economic collapse.
The common practices of people who inject drugs in Ukraine and in other countries in the region, such as social injecting, syringe sharing, and using common containers, increase the risk of transmitting HIV. Public health interventions such as needle exchange can limit these risk factors and have been gradually implemented in these countries. In 2007, Ukraine approved the use of methadone substitution therapy and the current target is for 11,000 people who inject drugs to be enrolled in substitution therapy by 2011. Furthermore, since treatment for HIV-infected individuals is also necessary, national HIV control plans included a target of 90% antiretroviral therapy (ART) coverage by 2010 but in 2007 less than 10% of the 91,000 eligible people received treatment. Although the number of people who inject drugs and who receive ART is unknown, physicians are often reluctant to treat people who inject drugs using ART owing to alleged poor compliance.
Why Was This Study Done?
As resources for HIV interventions in the region are limited, it is important to investigate the appropriate balance between investments in methadone substitution therapy and ART in order to maximize benefits to public health. Several studies have analyzed the cost effectiveness of methadone substitution therapy in similar settings but have not considered tradeoffs between ART and methadone substitution therapy. Therefore, to provide insights into the appropriate public health investment in methadone substitution therapy and ART in Ukraine, the researchers evaluated the public health effectiveness and cost effectiveness of different strategies for scaling up methadone substitution therapy and/or expanding ART.
What Did the Researchers Do and Find?
The researchers developed a model to accommodate different population groups: people who inject drugs on substitution therapy with methadone; people who inject opiates and do not take any substitution therapy; and people who do not inject any drugs, hence do not need substitution therapy. The researchers inputted Ukraine country-level data into this model and used current HIV trends in Ukraine to make rational assumptions on possible future trends and scenarios. They considered scenarios expanding methadone substitution therapy availability, increasing acces to ART, or both. Then, the researchers measured health care costs, quality-adjusted life years (QALYs), HIV prevalence, infections averted, and incremental cost effectiveness for the different scenarios. They found that after 20 years, HIV prevalence reached 67.2% in people who inject drugs and 0.88% in people who do not inject drugs without further interventions. Offering methadone substitution therapy to 25% of people who inject drugs was the most effective strategy in reducing prevalence of HIV and was also the most cost effective, averting 4,700 infections and adding 75,700 QALYs versus the status quo at $530/QALY gained. Expanding both methadone substitution therapy and ART was also a highly cost effective option, adding 105,000 QALYs at US$1,120/QALY gained versus the methadone substitution therapy-only strategy. Offering ART to 80% of eligible people who did not inject drugs, and 10% of people who injected drugs averted only 1,800 infections, and added 76,400 QALYs at $1,330/QALY gained.
What Do These Findings Mean?
The results show that methadone substitution-focused therapeutic scenarios are the most cost effective, and that benefits increase with the scale of the project, even among people who do not inject drugs. This makes a methadone substitution strategy a highly cost-effective option for addressing the growing HIV epidemic in Ukraine. Therefore, if it is not feasible to invest in large-scale methadone substitution programs for any reason, political circumstances for example, providing as much methadone substitution as is acceptable is still desirable. While substitution therapy appears to avert the most HIV infections, expanded ART provides the largest total increase in QALYs. Thus, methadone substitution therapy and ART offer complementary benefits. Because the HIV epidemic in Ukraine is representative of the HIV epidemic in Eastern Europe and Central Asia, the cost-effective strategies that the researchers have identified may help inform all decision makers faced with a mixed HIV epidemic.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000423.
Alliance provides information on its work supporting community action on AIDS in Ukraine
USAID provides an HIV/AIDS Health Profile for Ukraine
UNICEF provides information about its activities to help Ukraine fight rising HIV/AIDS infection rates
International Harm Reduction Association provides information about the status of harm reduction interventions such as methadone substitution therapy around the world
doi:10.1371/journal.pmed.1000423
PMCID: PMC3046988  PMID: 21390264
19.  Evaluation of cardiovascular biomarkers in a randomized trial of fosamprenavir/ritonavir vs. efavirenz with abacavir/lamivudine in underrepresented, antiretroviral-naïve, HIV-infected patients (SUPPORT): 96-week results 
BMC Infectious Diseases  2013;13:269.
Background
Rates of cardiovascular disease are higher among HIV-infected patients as a result of the complex interplay between traditional risk factors, HIV-related inflammatory and immunologic changes, and effects of antiretroviral therapy (ART). This study prospectively evaluated changes in cardiovascular biomarkers in an underrepresented, racially diverse, HIV-1-infected population receiving abacavir/lamivudine as backbone therapy.
Methods
This 96-week, open-label, randomized, multicenter study compared once-daily fosamprenavir/ritonavir 1400/100 mg and efavirenz 600 mg, both with ABC/3TC 600 mg/300 mg, in antiretroviral-naïve, HLA-B*5701-negative adults without major resistance mutations to study drugs. We evaluated changes from baseline to weeks 4, 12, 24, 48, and 96 in interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), soluble vascular adhesion molecule-1 (sVCAM-1), d-dimer, plasminogen, and fibrinogen. Biomarker data were log-transformed before analysis, and changes from baseline were described using geometric mean ratios.
Results
This study enrolled 101 patients (51 receiving fosamprenavir/ritonavir; 50 receiving efavirenz): 32% female, 60% African American, and 38% Hispanic/Latino; 66% (67/101) completed 96 weeks on study. At week 96, levels of IL-6, sVCAM-1, d-dimer, fibrinogen, and plasminogen were lower than baseline in both treatment groups, and the decrease was statistically significant for sVCAM-1 (fosamprenavir/ritonavir and efavirenz), d-dimer (fosamprenavir/ritonavir and efavirenz), fibrinogen (efavirenz), and plasminogen (efavirenz). Values of hs-CRP varied over time in both groups, with a significant increase over baseline at Weeks 4 and 24 in the efavirenz group. At week 96, there was no difference between the groups in the percentage of patients with HIV-1 RNA <50 copies/mL (fosamprenavir/ritonavir 63%; efavirenz 66%) by ITT missing-equals-failure analysis. Treatment-related grade 2–4 adverse events were more common with efavirenz (32%) compared with fosamprenavir/ritonavir (20%), and median lipid concentrations increased in both groups over 96 weeks of treatment.
Conclusions
In this study of underrepresented patients, treatment with abacavir/lamivudine combined with either fosamprenavir/ritonavir or efavirenz over 96 weeks, produced stable or declining biomarker levels except for hs-CRP, including significant and favorable decreases in thrombotic activity (reflected by d-dimer) and endothelial activation (reflected by sVCAM-1). Our study adds to the emerging data that some cardiovascular biomarkers are decreased with initiation of ART and control of HIV viremia.
Trial registration
ClinicalTrials.gov identifier NCT00727597
doi:10.1186/1471-2334-13-269
PMCID: PMC3685599  PMID: 23741991
Abacavir; Cardiovascular biomarker; Efavirenz; Fosamprenavir; HIV; Lamivudine; Minority; Ritonavir; Underrepresented
20.  Antigen Load and Viral Sequence Diversification Determine the Functional Profile of HIV-1–Specific CD8+ T Cells 
PLoS Medicine  2008;5(5):e100.
Background
Virus-specific CD8+ T lymphocytes play a key role in the initial reduction of peak viremia during acute viral infections, but display signs of increasing dysfunction and exhaustion under conditions of chronic antigen persistence. It has been suggested that virus-specific CD8+ T cells with a “polyfunctional” profile, defined by the capacity to secrete multiple cytokines or chemokines, are most competent in controlling viral replication in chronic HIV-1 infection. We used HIV-1 infection as a model of chronic persistent viral infection to investigate the process of exhaustion and dysfunction of virus-specific CD8+ T cell responses on the single-epitope level over time, starting in primary HIV-1 infection.
Methods and Findings
We longitudinally analyzed the polyfunctional epitope-specific CD8+ T cell responses of 18 patients during primary HIV-1 infection before and after therapy initiation or sequence variation in the targeted epitope. Epitope-specific CD8+ T cells responded with multiple effector functions to antigenic stimulation during primary HIV-1 infection, but lost their polyfunctional capacity in response to antigen and up-regulated programmed death 1 (PD-1) expression with persistent viremic infection. This exhausted phenotype significantly decreased upon removal of stimulation by antigen, either in response to antiretroviral therapy or by reduction of epitope-specific antigen load in the presence of ongoing viral replication, as a consequence of in vivo selection of cytotoxic T lymphocyte escape mutations in the respective epitopes. Monofunctionality increased in CD8+ T cell responses directed against conserved epitopes from 49% (95% confidence interval 27%–72%) to 76% (56%–95%) (standard deviation [SD] of the effect size 0.71), while monofunctionality remained stable or slightly decreased for responses directed against escaped epitopes from 61% (47%–75%) to 56% (42%–70%) (SD of the effect size 0.18) (p < 0.05).
Conclusion
These data suggest that persistence of antigen can be the cause, rather than the consequence, of the functional impairment of virus-specific T cell responses observed during chronic HIV-1 infection, and underscore the importance of evaluating autologous viral sequences in studies aimed at investigating the relationship between virus-specific immunity and associated pathogenesis.
Marcus Altfeld and colleagues suggest that the exhaustion of virus-specific CD8+ T cells during chronic HIV infection likely results from the persistence of antigen.
Editors' Summary
Background.
Viruses are small infectious agents responsible for many human diseases, including acquired immunodeficiency syndrome (AIDS). Like other viruses, the human immunodeficiency virus 1 (HIV-1; the cause of AIDS) enters human cells and uses the cellular machinery to replicate before bursting out of its temporary home. During the initial stage of HIV infection, a particular group of cells in the human immune system, CD8+ T cells, are thought to be important in controlling the level of the virus. These immune system cells recognize pieces of viral protein called antigens displayed on the surface of infected cells; different subsets of CD8+ T cells recognize different antigens. When a CD8+ T cell recognizes its specific antigen (or more accurately, a small part of the antigen called an “epitope”), it releases cytotoxins (which kill the infected cells) and cytokines, proteins that stimulate CD8+ T cell proliferation and activate other parts of the immune system. With many viruses, when a person first becomes infected (an acute viral infection), antigen-specific CD8+ T cells completely clear the infection. But with HIV-1 and some other viruses, these cells do not manage to remove all the viruses from the body and a chronic (long-term) infection develops, during which the immune system is constantly exposed to viral antigen.
Why Was This Study Done?
In HIV-1 infections (and other chronic viral infections), virus-specific CD8+ T cells lose their ability to proliferate, to make cytokines, and to kill infected cells as patients progress to the long-term stages of infection. That is, the virus-specific CD8+ T cells gradually lose their “effector” functions and become functionally impaired or “exhausted.” “Polyfunctional” CD8+ T cells (those that release multiple cytokines in response to antigen) are believed to be essential for an effective CD8+ T cell response, so scientists trying to develop HIV-1 vaccines would like to stimulate the production of this type of cell. To do this they need to understand why these polyfunctional cells are lost during chronic infections. Is their loss the cause or the result of viral persistence? In other words, does the constant presence of viral antigen lead to the exhaustion of CD8+ T cells during chronic HIV infection? In this study, the researchers investigate this question by looking at the polyfunctionality of CD8+ cells responding to several different viral epitopes at various times during HIV-1 infection, starting very early after infection with HIV-1 had occurred.
What Did the Researchers Do and Find?
The researchers enrolled 18 patients recently infected with HIV-1 and analyzed their CD8+ T cell responses to specific epitopes at various times after enrollment using a technique called flow cytometry. They found that the epitope-specific CD8+ cells produced several effector proteins after antigen stimulation during the initial stage of HIV-1 infection, but lost their polyfunctionality in the face of persistent viral infection. The CD8+ T cells also increased their production of programmed death 1 (PD-1), a protein that has been shown to be associated with the functional impairment of CD8+ T cells. Some of the patients began antiretroviral therapy during the study, and the researchers found that this treatment, which reduced the viral load, reversed CD8+ T cell exhaustion. Finally, the appearance in the patients' blood of viruses that had made changes in the specific epitopes recognized by the CD8+ T cells to avoid being killed by these cells, also reversed the exhaustion of the T cells recognizing these particular epitopes.
What Do These Findings Mean?
These findings suggest that the constant presence of HIV-1 antigen causes the functional impairment of virus-specific CD8+ T cell responses during chronic HIV-1 infections. Treatment with antiretroviral drugs reversed this functional impairment by reducing the amount of antigen in the patients. Similarly, the appearance of viruses with altered epitopes, which effectively reduced the amount of antigen recognized by those epitope-specific CD8+ T cells without reducing the viral load, also reversed T cell exhaustion. These results would not have been seen if the functional impairment of CD8+ cells were the cause rather than the result of antigen persistence. By providing new insights into how the T cell response to viruses evolves during persistent viral infections, these findings should help in the design of vaccines against HIV and other viruses that cause chronic viral infections.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050100.
Read a related PLoS Medicine Research in Translation article
Learn more from the researchers' Web site, the Partners AIDS Research Center
Wikipedia has a page on cytotoxic T cells (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
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 detailed article on the immunopathogenesis of HIV infection
NAM, a UK registered charity, provides information about all aspects of HIV and AIDS, including a fact sheet on the stages of HIV infection and on the immune response to HIV
Information is available from Avert, an international AIDS charity, on all aspects of HIV/AIDS, including information on the stages of HIV infection
doi:10.1371/journal.pmed.0050100
PMCID: PMC2365971  PMID: 18462013
21.  HIV-1 DNA predicts disease progression and post-treatment virological control 
eLife  2014;3:e03821.
In HIV-1 infection, a population of latently infected cells facilitates viral persistence despite antiretroviral therapy (ART). With the aim of identifying individuals in whom ART might induce a period of viraemic control on stopping therapy, we hypothesised that quantification of the pool of latently infected cells in primary HIV-1 infection (PHI) would predict clinical progression and viral replication following ART. We measured HIV-1 DNA in a highly characterised randomised population of individuals with PHI. We explored associations between HIV-1 DNA and immunological and virological markers of clinical progression, including viral rebound in those interrupting therapy. In multivariable analyses, HIV-1 DNA was more predictive of disease progression than plasma viral load and, at treatment interruption, predicted time to plasma virus rebound. HIV-1 DNA may help identify individuals who could safely interrupt ART in future HIV-1 eradication trials.
DOI: http://dx.doi.org/10.7554/eLife.03821.001
eLife digest
HIV is a virus that can hide in, and hijack, the cells of the immune system and force them to make new copies of the virus. This eventually destroys the infected cells and weakens the ability of a person with HIV to fight off infections and disease. If diagnosed early and treated, most people with HIV now live long and healthy lives and do not develop AIDS—the last stage of HIV infection when previously harmless, opportunistic infections can become life-threatening. However, there are still numerous hurdles and challenges that must be overcome before a cure for HIV/AIDS can be developed.
Treatment with drugs called antiretrovirals can reduce the amount of the HIV virus circulating in an infected person's bloodstream to undetectable levels. However, when HIV infects a cell, the virus inserts a copy of its genetic material into the cell's DNA—and, for most patients, antiretroviral treatment does not tackle these ‘hidden viruses’. As such, and in spite of their side-effects, antiretroviral drugs have to be taken for life in case the hidden viruses re-emerge.
As research into a cure for HIV/AIDS gathers momentum, patients who might be candidates for new experimental treatments will need to be identified. Although it is not recommended as part of standard clinical care, the only way to test if a patient's viral levels would remain suppressed without the drugs would be to temporarily stop the treatment under the close supervision of a physician. As such, a new method is needed to identify if there are patients who might benefit from stopping antiretroviral therapy, and more importantly, those who might not.
Williams, Hurst et al. have now tested whether measuring the levels of HIV DNA directly might help to predict if, and when, the virus might re-emerge (or rebound). In a group of HIV patients participating in a clinical trial, those with higher levels of HIV DNA at the point that the treatment was stopped were found to experience faster viral rebound than those with lower levels of HIV DNA. This method could therefore identify those patients who are at the greatest risk of HIV viral rebound, and are therefore unlikely to benefit if their treatment is interrupted.
Williams, Hurst et al. also found that measuring the levels of HIV DNA could help to predict how the disease would progress in treated and untreated patients. Furthermore, these predictions were more accurate than those based on measuring the amount of the virus circulating in a patient's body.
The next challenge is to identify other methods to distinguish patients who may remain ‘virus-free’ for a period without treatment, from those who would not. With this achieved, it might be possible to identify the mechanisms that determine why the virus comes back and so develop new treatments to stop this happening. This would make developing a cure for HIV/AIDS a much more tangible prospect.
DOI: http://dx.doi.org/10.7554/eLife.03821.002
doi:10.7554/eLife.03821
PMCID: PMC4199415  PMID: 25217531
HIV-1; reservoir; antiretroviral therapy; cure; primary infection; human
22.  Markers of inflammation and CD8+ T-cell activation, but not monocyte activation are associated with subclinical carotid artery disease in HIV 
HIV medicine  2013;14(6):385-390.
OBJECTIVE
To explore the relationships between lymphocyte and monocyte activation, inflammation, and subclinical vascular disease among HIV-1 infected patients on antiretroviral therapy.
METHODS
Baseline mean common carotid artery (CCA) intima-media thickness (IMT) and carotid plaque (IMT >1.5cm) were evaluated in the first 60 subjects enrolled in the Stopping Atherosclerosis and Treating Unhealthy bone with RosuvastatiN in HIV (SATURN-HIV) trial. All subjects were adults, on stable ART with evidence of heightened T-cell activation (CD8+CD38+HLA-DR+ ≥19%) or increased inflammation (high sensitivity C-reactive protein ≥2mg/L). All had fasting LDL-cholesterol ≤130mg/dL.
RESULTS
78% were men and 65% African-American. Median (IQR) age and CD4+ count were 47(43,52) years and 648(511, 857) cells/µL, respectively. All had HIV-1 RNA<400 cps/mL. Mean CCA-IMT was correlated with log-transformed CD8+CD38+HLA-DR+% (r=0.326, p=0.043), interleukin-6 (r=0.283, p=0.028), soluble vascular cell adhesion molecule (sVCAM, r=0.434, p=0.004), tumor necrosis factor-α receptor-I (TNFR-I, r=0.591, p=<0.0001) and fibrinogen (r=0.257, p=0.047). After adjustment for traditional CVD risk factors, the association with TNFR-I (p=0.007) and fibrinogen (p=0.033) remained significant. Subjects with plaque (n=22, 37%) were older [51(7.7) vs. 43(9.4) years, mean(SD), p=0.002], had higher CD8+CD38+HLA-DR+% [31(24, 41) vs. 23(20,29)%, median(IQR), p=0.046] and higher sVCAM [737(159) vs. 592(160) ng/mL, p=0.008] compared to those without plaque. Pro-inflammatory monocyte subsets and serum markers of monocyte activation (soluble CD163 and soluble CD14) were not associated with CCA-IMT or plaque.
CONCLUSIONS
Participants in SATURN-HIV have a high level of inflammation and immune activation that is associated with subclinical vascular disease despite low serum LDL-C.
doi:10.1111/hiv.12013
PMCID: PMC3640592  PMID: 23332012
T-cell activation; Monocyte activation; Inflammation; Carotid intima-media thickness; Subclinical atherosclerosis
23.  Changes in HIV Incidence among People Who Inject Drugs in Taiwan following Introduction of a Harm Reduction Program: A Study of Two Cohorts 
PLoS Medicine  2014;11(4):e1001625.
Kenrad Nelson and colleagues report on the association between HIV incidence and exposure to a national harm-reduction program among people who inject drugs in Taiwan.
Please see later in the article for the Editors' Summary
Background
Harm reduction strategies for combating HIV epidemics among people who inject drugs (PWID) have been implemented in several countries. However, large-scale studies using sensitive measurements of HIV incidence and intervention exposures in defined cohorts are rare. The aim of this study was to determine the association between harm reduction programs and HIV incidence among PWID.
Methods and Findings
The study included two populations. For 3,851 PWID who entered prison between 2004 and 2010 and tested HIV positive upon incarceration, we tested their sera using a BED HIV-1 capture enzyme immunoassay to estimate HIV incidence. Also, we enrolled in a prospective study a cohort of 4,357 individuals who were released from prison via an amnesty on July 16, 2007. We followed them with interviews at intervals of 6–12 mo and by linking several databases. A total of 2,473 participants who were HIV negative in January 2006 had interviews between then and 2010 to evaluate the association between use of harm reduction programs and HIV incidence. We used survival methods with attendance at methadone clinics as a time-varying covariate to measure the association with HIV incidence. We used a Poisson regression model and calculated the HIV incidence rate to evaluate the association between needle/syringe program use and HIV incidence. Among the population of PWID who were imprisoned, the implementation of comprehensive harm reduction programs and a lower mean community HIV viral load were associated with a reduced HIV incidence among PWID. The HIV incidence in this population of PWID decreased from 18.2% in 2005 to 0.3% in 2010. In an individual-level analysis of the amnesty cohort, attendance at methadone clinics was associated with a significantly lower HIV incidence (adjusted hazard ratio: 0.20, 95% CI: 0.06–0.67), and frequent users of needle/syringe program services had lower HIV incidence (0% in high NSP users, 0.5% in non NSP users). In addition, no HIV seroconversions were detected among prison inmates.
Conclusions
Although our data are affected by participation bias, they strongly suggest that comprehensive harm- reduction services and free treatment were associated with reversal of a rapidly emerging epidemic of HIV among PWID.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
About 35 million people worldwide are currently infected with HIV, the virus that causes AIDS, and about 2.3 million people become newly infected every year. HIV is mainly transmitted through unprotected sex with an infected partner. However, people who inject drugs (PWID) have a particularly high risk of HIV infection because blood transfer through needle and syringe sharing can transmit the virus. It is estimated that 5%–10% of all people living with HIV are PWID. Indeed, in some regions of the world the primary route of HIV transmission is through shared drug injection equipment and the prevalence (the proportion of a population that has a specific disease) of HIV infection among PWID is very high. In Asia, for example, more than a quarter of PWID are HIV positive. Because the high prevalence of HIV among PWID poses a global health challenge, bodies such as the Joint United Nations Programme on HIV/AIDS endorse harm reduction strategies to prevent risky injection behaviors among PWID. These strategies include the provision of clean needles and syringes, opioid substitution therapy such as methadone maintenance treatment, and antiretroviral treatment for HIV-positive PWID.
Why Was This Study Done?
Although harm reduction strategies for combating HIV epidemics among PWID have been implemented in several countries, few large-scale studies have examined the association between HIV incidence (the proportion of new cases of HIV in a population per year) and exposure to harm reduction programs among PWID. In this cohort study (an investigation that determines the characteristics of a group of people and then follows them over time), the researchers determine the association between harm reduction programs and HIV incidence among PWID in Taiwan. HIV infections used to be rare among the 60,000 PWID living in Taiwan, but after the introduction of a new HIV strain into the country in 2003, an HIV epidemic spread rapidly. In response, the Taiwanese government introduced a pilot program of harm reduction that included the provision of clean needles and syringes and health education in July 2005. The program was expanded to include methadone maintenance treatment in early 2006 and implemented nationwide in June 2006.
What Did the Researchers Do and Find?
The researchers enrolled two study populations. The first cohort comprised 3,851 PWID who were incarcerated for illicit drug use between 2004 and 2010 and who tested positive for HIV upon admission into prison. By using the BED assay, which indicates whether an HIV infection is recent, the researchers were able to determine the HIV incidence among the prisoners. In 2004, the estimated HIV incidence among prisoners with a history of drug injection was 6.44%. The incidence peaked in 2005 at 18.2%, but fell to 0.3% in 2010.
The second study population comprised 2,473 individuals who were HIV negative on January 1, 2006, and who had been incarcerated for drug use crimes but were released on July 16, 2007, during an amnesty. The researchers regularly interviewed these participants between their release and 2010 about their use of harm reduction interventions, and obtained other data about them (for example, diagnosis of HIV infection) from official databases. Analysis of all these data indicated that, in this cohort, attendance at methadone maintenance treatment clinics and frequent use of needle and syringe services were both associated with a significantly lower HIV incidence.
What Do These Findings Mean?
These findings suggest that the introduction of a comprehensive harm reduction program in Taiwan was associated with a significant reduction in the HIV incidence rate among PWID. These findings must be interpreted with caution, however. First, because the participants in the study were selected from PWID with histories of incarceration, the findings may not be representative of all PWID in Taiwan or of PWID in other countries. Second, PWID who chose to use needle and syringe services or methadone maintenance treatment clinics might have shared other unknown characteristics that affected their risk of HIV infection. Finally, some of the reduction in HIV incidence seen during the study is likely to be associated with the availability of free treatment, which has been offered to all HIV-positive individuals in Taiwan since 1997. Despite these limitations, these findings suggest that countries with a high prevalence and incidence of HIV among PWID should provide comprehensive harm reduction services to their populations to reduce risky drug injection behaviors.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001625.
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 injecting drug users and HIV/AIDS and on harm reduction and HIV prevention (in English and Spanish)
The US National Institute on Drug Abuse also provides information about drug abuse and HIV/AIDS (in English and Spanish)
The 2013 UNAIDS World AIDS Day report provides up-to-date information about the AIDS epidemic and efforts to halt it
Personal stories about living with HIV/AIDS are available through Avert, Nam/aidsmap, and Healthtalkonline
doi:10.1371/journal.pmed.1001625
PMCID: PMC3979649  PMID: 24714449
24.  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
25.  Inflammatory and Coagulation Biomarkers and Mortality in Patients with HIV Infection 
PLoS Medicine  2008;5(10):e203.
Background
In the Strategies for Management of Anti-Retroviral Therapy trial, all-cause mortality was higher for participants randomized to intermittent, CD4-guided antiretroviral treatment (ART) (drug conservation [DC]) than continuous ART (viral suppression [VS]).
We hypothesized that increased HIV-RNA levels following ART interruption induced activation of tissue factor pathways, thrombosis, and fibrinolysis.
Methods and Findings
Stored samples were used to measure six biomarkers: high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), amyloid A, amyloid P, D-dimer, and prothrombin fragment 1+2. Two studies were conducted: (1) a nested case–control study for studying biomarker associations with mortality, and (2) a study to compare DC and VS participants for biomarker changes. For (1), markers were determined at study entry and before death (latest level) for 85 deaths and for two controls (n = 170) matched on country, age, sex, and date of randomization. Odds ratios (ORs) were estimated with logistic regression. For each biomarker, each of the three upper quartiles was compared to the lowest quartile. For (2), the biomarkers were assessed for 249 DC and 250 VS participants at study entry and 1 mo following randomization. Higher levels of hsCRP, IL-6, and D-dimer at study entry were significantly associated with an increased risk of all-cause mortality. Unadjusted ORs (highest versus lowest quartile) were 2.0 (95% confidence interval [CI], 1.0–4.1; p = 0.05), 8.3 (95% CI, 3.3–20.8; p < 0.0001), and 12.4 (95% CI, 4.2–37.0; p < 0.0001), respectively. Associations were significant after adjustment, when the DC and VS groups were analyzed separately, and when latest levels were assessed. IL-6 and D-dimer increased at 1 mo by 30% and 16% in the DC group and by 0% and 5% in the VS group (p < 0.0001 for treatment difference for both biomarkers); increases in the DC group were related to HIV-RNA levels at 1 mo (p < 0.0001). In an expanded case–control analysis (four controls per case), the OR (DC/VS) for mortality was reduced from 1.8 (95% CI, 1.1–3.1; p = 0.02) to 1.5 (95% CI, 0.8–2.8) and 1.4 (95% CI, 0.8–2.5) after adjustment for latest levels of IL-6 and D-dimer, respectively.
Conclusions
IL-6 and D-dimer were strongly related to all-cause mortality. Interrupting ART may further increase the risk of death by raising IL-6 and D-dimer levels. Therapies that reduce the inflammatory response to HIV and decrease IL-6 and D-dimer levels may warrant investigation.
Trial Registration: ClinicalTrials.gov (NCT00027352).
Analyzing biomarker data from participants in a previous randomized controlled trial of continuous versus interrupted HIV treatment (the SMART trial), James Neaton and colleagues find that mortality was related to IL-6 and fibrin D-dimers.
Editors' Summary
Background.
Globally, more than 30 million people are infected with the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome (AIDS). HIV infects and destroys immune system cells (including CD4 cells, a type of lymphocyte). The first stage of HIV infection can involve a short flu-like illness but in the second stage, which can last many years, HIV replicates in the lymph glands (small immune system organs throughout the body) without causing any symptoms. Eventually, however, the immune system becomes so damaged that HIV-infected individuals begin to succumb to “opportunistic” infections (for example, bacterial pneumonia) and cancers (in particular, Karposi sarcoma) that the immune system would normally prevent. AIDS itself is characterized by one or more severe opportunistic infections or cancers (so-called AIDS-related diseases) and by a low blood CD4 cell count. HIV infections cannot be cured but antiretroviral therapy (ART)—combinations of powerful antiretroviral drugs—can keep them in check, so many HIV-positive people now have substantially improved life expectancy.
Why Was This Study Done?
Unfortunately, the effectiveness of ART sometimes wanes over time and prolonged ART can cause unpleasant side effects. Consequently, alternative ART regimens are continually being tested in clinical trials. In the Strategies for Management of Anti-Retroviral Therapy (SMART) trial, for example, HIV-positive patients received either continuous ART (the viral suppression or VS arm), or ART only when their CD4 cell counts were below 250 cells/mm3 (the drug conservation or DC arm; the normal adult CD4 cell count is about 1,000 cells/mm3). Unexpectedly, more people died in the DC arm than in the VS arm from non-AIDS diseases (including heart and circulation problems), a result that led to the trial being stopped early. One possible explanation for these excess deaths is that increased HIV levels following ART interruption might have induced an inflammatory response (a non-specific immune response that occurs with infection or wounding) and/or a hypercoagulable state (a condition in which blood clots form inside undamaged blood vessels) and that these changes increased the risk of death from non-AIDS diseases. In this study, the researchers test this hypothesis.
What Did the Researchers Do and Find?
The researchers measured the levels of proteins that indicate the presence of inflammation or increased coagulation (biomarkers) in stored blood samples from the 85 people who died during the SMART trial (55 and 30 of the participants assigned to receive DC and VS, respectively) and from 170 survivors who served as comparison (control) participants. (Two control participants were “matched” to each participant who had died (cases). In this “case-control” study, an increased risk of death was associated with higher levels at study entry of the inflammation biomarkers high-sensitivity C-reactive protein (hsCRP) and interleukin 6 (IL-6) and of the coagulation biomarker D-dimer. The risk of death among people with hsCRP values in the highest quarter of measured values was twice that among people with hsCRP values in the lowest quarter (this is expressed as an odds ratio of 2). For IL-6 and D-dimer, the equivalent odds ratios were 8.3 and 12.4, respectively. Furthermore, increases in hsCRP, IL-6 and D-dimer after study entry were associated with an increased risk of death. The researchers also measured blood levels of the same biomarkers in 250 randomly chosen patients from each of the two treatment arms. IL-6 levels increased by 30% over the first month of the trial in the DC arm but were unchanged in the VS arm. Over the same period, D-dimer levels increased by 16% and 5% in the DC and VS arms, respectively. Increases in both markers in the DC arm were related to HIV RNA levels after one month.
What Do These Findings Mean?
Taken together, these findings suggest that HIV-induced activation of inflammation and coagulation increases the risk of death among HIV-positive patients and that interrupting ART further increases this risk, possibly by increasing IL-6 and D-dimer levels. Because only a small number of people died in this study, the relationship between these biomarkers and death and illness among treated and untreated HIV-positive individuals needs to be confirmed in further studies. However, these findings suggest that the development of therapies that reduce the effect that HIV replication has on inflammation and blood coagulation, or that reduce IL-6 and D-dimer levels, might extend the life-expectancy of HIV-positive people.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050203.
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS and about the SMART trial
HIV InSite has comprehensive information on all aspects of HIV/AIDS
Information is also available from Avert, an international AIDS charity, on HIV/AIDS
More information about the SMART trial is available on ClinicalTrials.gov, a database of clinical trials maintained by the US National Institutes of Health
doi:10.1371/journal.pmed.0050203
PMCID: PMC2570418  PMID: 18942885

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