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1.  Secondary Outcomes of a Pilot Randomized Trial of Azithromycin Treatment for Asthma 
PLoS Clinical Trials  2006;1(2):e11.
The respiratory pathogen Chlamydia pneumoniae (C. pneumoniae) produces acute and chronic lung infections and is associated with asthma. Evidence for effectiveness of antichlamydial antibiotics in asthma is limited. The primary objective of this pilot study was to investigate the feasibility of performing an asthma clinical trial in practice settings where most asthma is encountered and managed. The secondary objectives were to investigate (1) whether azithromycin treatment would affect any asthma outcomes and (2) whether C. pneumoniae serology would be related to outcomes. This report presents the secondary results.
Randomized, placebo-controlled, blinded (participants, physicians, study personnel, data analysts), allocation-concealed parallel group clinical trial.
Community-based health-care settings located in four states and one Canadian province.
Adults with stable, persistent asthma.
Azithromycin (six weekly doses) or identical matching placebo, plus usual community care.
Outcome Measures:
Juniper Asthma Quality of Life Questionnaire (Juniper AQLQ), symptom, and medication changes from baseline (pretreatment) to 3 mo posttreatment (follow-up); C. pneumoniae IgG and IgA antibodies at baseline and follow-up.
Juniper AQLQ improved by 0.25 (95% confidence interval; −0.3, 0.8) units, overall asthma symptoms improved by 0.68 (0.1, 1.3) units, and rescue inhaler use decreased by 0.59 (−0.5, 1.6) daily administrations in azithromycin-treated compared to placebo-treated participants. Baseline IgA antibodies were positively associated with worsening overall asthma symptoms at follow-up (p = 0.04), but IgG was not (p = 0.63). Overall asthma symptom improvement attributable to azithromycin was 28% in high IgA participants versus 12% in low IgA participants (p for interaction = 0.27).
Azithromycin did not improve Juniper AQLQ but appeared to improve overall asthma symptoms. Larger community-based trials of antichlamydial antibiotics for asthma are warranted.
Editorial Commentary
Background: Chlamydia pneumoniae is a common bacterium thought to be responsible for a substantial proportion of community-acquired pneumonia and bronchitis infections. There is some observational evidence associating chronic C. pneumoniae infection with more severe symptoms in people with asthma. However, there are very little data from clinical trials determining whether treatment with antibiotics active against C. pneumoniae has an effect on the control of asthma.
What this trial shows: In this trial, the researchers randomized 45 adults who were being treated for asthma in primary care to receive either azithromycin (an antibiotic active against C. pneumoniae) or placebo, in addition to their usual asthma care. Participants were followed up for 3 mo after completion of treatment, during which time participants recorded data relating to their overall symptoms and daily activities on a 5-point scale, and use of bronchodilators. At the start of the trial, and at 3-mo follow-up, participants also completed a quality-of-life questionnaire using a validated scale. The primary objective of this trial was to investigate the feasibility of running an asthma trial in the primary care setting, and in using IVR telephone systems to collect the outcome data, reported in [13]. In this paper, the asthma outcomes are reported. Participants receiving azithromycin did not show a significant improvement in quality of life at 3-mo follow-up as compared to participants receiving placebo. However, the investigators did see a significant improvement in the overall symptoms recorded by participants receiving azithromycin, as compared to placebo.
Strengths and limitations: The randomization methods in the trial were appropriate, as was the choice of placebo as a comparison for azithromycin. However, the number of participants in the trial was small, and it is likely that many more participants would need to be recruited to conclusively demonstrate or disprove an effect of azithromycin on asthma-related quality of life. Further, the trial used three different measures for asthma outcomes: (1) the quality-of-life questionnaire, (2) measurement of symptoms and daily activities on a 5-point scale, and (3) bronchodilator use. Only the quality-of-life questionnaire is validated, making it difficult to compare the results with those of other asthma trials.
Contribution to the evidence: This trial provides suggestive evidence that azithromycin may have benefits in the treatment of asthma, but should not on its own lead to a change in practice. The study provides a good basis for a larger randomized trial of such treatments, which would need to assess reliably the effect of these drugs not only on symptoms but also on quality of life. Information gained from this trial would help to design several aspects of future studies, e.g., their size, follow-up duration, and suitable outcome measures.
PMCID: PMC1488900  PMID: 16871333
2.  Empowering pharmacists in asthma management through interactive SMS (EmPhAsIS): study protocol for a randomized controlled trial 
Trials  2014;15(1):488.
Medication regimens for asthma are particularly vulnerable to adherence problems because of the requirement for long-term use and periods of symptom remission experienced by patients. Pharmacists are suited to impact medication adherence given their training, skills, and frequent contact with patients. The Empowering pharmacists in asthma management through interactive SMS (EmPhAsIS) trial involves an intervention leveraging mobile health (mHealth) technology to support community pharmacy practice with the hypothesis of improved medication adherence in asthma.
This study is a pragmatic pharmacy-based, cluster, randomized controlled trial with 12 months of intervention delivery and follow-up. Pharmacies (the clusters) will be randomized at a 1:1 ratio to provide intervention or usual care. The EmPhAsIS intervention consists of patient asthma education, short message service (SMS)-based monthly assessment of adherence, and follow-up of non-adherent individuals by community pharmacists. There are no inclusion or exclusion criteria for pharmacies. Patients are eligible if they: are 14 years of age or older, fill a prescription for inhaled corticosteroid (either monotherapy or in a combination inhaler with long-acting beta-agonists), have been diagnosed with asthma, possess a mobile phone with SMS capabilities, and have no communication difficulties such as inability to communicate in English, or significant impairment in vision, hearing, or speech. The primary outcome is adherence to inhaled corticosteroids ascertained by the medication possession ratio, the ratio of the days of medication supplied to days in a given time interval. This study will also evaluate secondary outcomes including: asthma control, asthma-related quality of life, asthma-related hospital admissions, and use of reliever medications during the follow-up period. A nested economic evaluation using a probabilistic decision-analytic model will be used to perform a cost-effectiveness analysis from the societal perspective of the intervention compared with usual care over a 10-year time horizon.
Considering the prevalence of asthma, the extent of the non-adherence problem in this disease, and the availability of effective treatments, there is a tremendous potential to reduce the burden of asthma through improving adherence. This is the first study of an intervention based on mobile communication technology involving community pharmacists in asthma management.
Trial registration identifier: NCT02170883; date of registration: 19 June 2014.
PMCID: PMC4301403  PMID: 25494702
Asthma; Medication adherence; Inhaled corticosteroids; Cluster randomized controlled trial; Community pharmacy; Pharmacy practice research
3.  InSpire to Promote Lung Assessment in Youth: Evolving the Self-Management Paradigms of Young People With Asthma 
Medicine 2.0  2013;2(1):e1.
Asthma is the most common chronic disease in childhood, disproportionately affecting urban, minority, and disadvantaged children. Individualized care plans supported by daily lung-function monitoring can reduce morbidity and mortality. However, despite 20 years of interventions to increase adherence, only 50% of US youth accurately follow their care plans, which leads to millions of preventable hospitalizations, emergency room visits, and sick days every year. We present a feasibility study of a novel, user-centered approach to increasing young people’s lung-function monitoring and asthma self-care. Promoting Lung Assessment in Youth (PLAY) helps young people become active managers of their asthma through the Web 2.0 principles of participation, cocreation, and information sharing. Specifically, PLAY combines an inexpensive, portable spirometer with the motivational power and convenience of mobile phones and virtual-community gaming.
The objective of this study was to develop and pilot test InSpire, a fully functional interface between a handheld spirometer and an interactive game and individualized asthma-care instant-messaging system housed on a mobile phone.
InSpire is an application for mobile smartphones that creates a compelling world in which youth collaborate with their physicians on managing their asthma. Drawing from design-theory on global timer mechanics and role playing, we incentivized completing spirometry maneuvers by making them an engaging part of a game young people would want to play. The data can be sent wirelessly to health specialists and return care recommendations to patients in real-time. By making it portable and similar to applications normally desired by the target demographic, InSpire is able to seamlessly incorporate asthma management into their lifestyle.
We describe the development process of building and testing the InSpire prototype. To our knowledge, the prototype is a first-of-its kind mobile one-stop shop for asthma management. Feasibility testing in children aged 7 to 14 with asthma assessed likability of the graphical user interface as well as young people’s interest in our incentivizing system. Nearly 100% of children surveyed said they would play games like those in PLAY if they involved breathing into a spirometer. Two-thirds said they would prefer PLAY over the spirometer alone, whereas 1/3 would prefer having both. No children said they would prefer the spirometer over PLAY.
Previous efforts at home-monitoring of asthma in children have experienced rapid decline in adherence. An inexpensive monitoring technology combined with the computation, interactive communication, and display ability of a mobile phone is a promising approach to sustainable adherence to lung-function monitoring and care plans. An exciting game that redefines the way youth conduct health management by inviting them to collaborate in their health better can be an incentive and a catalyst for more far-reaching goals.
PMCID: PMC4084766  PMID: 25075232
pediatric asthma; chronic disease management; mobile phones; spirometry; gamification
4.  Effect of a Community-Based Nursing Intervention on Mortality in Chronically Ill Older Adults: A Randomized Controlled Trial 
PLoS Medicine  2012;9(7):e1001265.
Kenneth Coburn and colleagues report findings from a randomized trial evaluating the effects of a complex nursing intervention on mortality risk among older individuals diagnosed with chronic health conditions.
Improving the health of chronically ill older adults is a major challenge facing modern health care systems. A community-based nursing intervention developed by Health Quality Partners (HQP) was one of 15 different models of care coordination tested in randomized controlled trials within the Medicare Coordinated Care Demonstration (MCCD), a national US study. Evaluation of the HQP program began in 2002. The study reported here was designed to evaluate the survival impact of the HQP program versus usual care up to five years post-enrollment.
Methods and Findings
HQP enrolled 1,736 adults aged 65 and over, with one or more eligible chronic conditions (coronary artery disease, heart failure, diabetes, asthma, hypertension, or hyperlipidemia) during the first six years of the study. The intervention group (n = 873) was offered a comprehensive, integrated, and tightly managed system of care coordination, disease management, and preventive services provided by community-based nurse care managers working collaboratively with primary care providers. The control group (n = 863) received usual care. Overall, a 25% lower relative risk of death (hazard ratio [HR] 0.75 [95% CI 0.57–1.00], p = 0.047) was observed among intervention participants with 86 (9.9%) deaths in the intervention group and 111 (12.9%) deaths in the control group during a mean follow-up of 4.2 years. When covariates for sex, age group, primary diagnosis, perceived health, number of medications taken, hospital stays in the past 6 months, and tobacco use were included, the adjusted HR was 0.73 (95% CI 0.55–0.98, p = 0.033). Subgroup analyses did not demonstrate statistically significant interaction effects for any subgroup. No suspected program-related adverse events were identified.
The HQP model of community-based nurse care management appeared to reduce all-cause mortality in chronically ill older adults. Limitations of the study are that few low-income and non-white individuals were enrolled and implementation was in a single geographic region of the US. Additional research to confirm these findings and determine the model's scalability and generalizability is warranted.
Trial Registration NCT01071967
Please see later in the article for the Editors' Summary
Editors' Summary
In almost every country in the world, the proportion of people aged over 60 years is growing faster than any other age group because of increased life expectancy. This demographic change has several implications for public health, especially as older age is a risk factor for many chronic diseases—diseases of long duration and generally slow progression. Chronic diseases, such as heart disease, stroke, cancer, chronic respiratory diseases, and diabetes, are by far the leading cause of death in the world, representing almost two-thirds of all deaths. Therefore in most countries, the challenge of managing increasingly ageing populations who have chronic illnesses demands an urgent response and countries such as the United States are actively researching possible solutions.
Why Was This Study Done?
Some studies suggest that innovations in chronic disease management that are led by nurses may help address the epidemic of chronic diseases by increasing the quality and reducing the cost of care. However, to date, reports of the evaluation of such interventions lack rigor and do not provide evidence of improved long-term health outcomes or reduced health care costs. So in this study, the researchers used the gold standard of research, a randomized controlled trial, to examine the impact of a community-based nurse care management model for older adults with chronic illnesses in the United States as part of a series of studies supported by the Centers for Medicare and Medicaid Services.
What Did the Researchers Do and Find?
The researchers recruited eligible patients aged 65 years and over with heart failure, coronary heart disease, asthma, diabetes, hypertension, and/or hyperlipidemia who received traditional Medicare—a fee for service insurance scheme in which beneficiaries can choose to receive their care from any Medicare provider—from participating primary care practices in Pennsylvania. The researchers then categorized patients according to their risk on the basis of several factors including the number of chronic diseases each individual had before randomizing patients to receive usual care or the nurse-led intervention. The intervention included an individualized plan comprising education, symptom monitoring, medication, counseling for adherence, help identifying, arranging, and monitoring community health and social service referrals in addition to group interventions such as weight loss maintenance and exercise classes. The researchers checked whether any participating patients had died by using the online Social Security Death Master File. Then the researchers used a statistical model to calculate the risk of death in both groups.
Of the 1,736 patients the researchers recruited into the trial, 873 were randomized to receive the intervention and 863 were in the control group (usual care). The researchers found that 86 (9.9%) participants in the intervention group and 111 (12.9%) participants in the control group died during the study period, representing a 25% lower relative risk of death among the intervention group. However, when the researchers considered other factors, such as sex, age group, primary diagnosis, perceived health, number of medications taken, hospital stays in the past 6 months, and tobacco use in their statistical model, this risk was slightly altered—0.73 risk of death in the intervention group.
What Do These Findings Mean?
These findings suggest that that community-based nurse care management is associated with a reduction in all-cause mortality among older adults with chronic illnesses who are beneficiaries of the fee for service Medicare scheme in the United States. These findings also support the important role of nurses in improving health outcomes in this group of patients and show the feasibility of implementing this program in collaboration with primary care practices. Future research is needed to test the adaptability, scalability, and generalizability of this model of care.
Additional Information
Please access these Web sites via the online version of this summary at
This study is further discussed in a PLoS Medicine Perspective by Arlene Bierman
Information about the Centers for Medicare and Medicaid Services is available
The World Health Organization provides statistics on the prevalence of both chronic illness and ageing
Heath Quality Partners provide information about the study
PMCID: PMC3398966  PMID: 22815653
5.  A Pilot Study of an mHealth Application for Healthcare Workers: Poor Uptake Despite High Reported Acceptability at a Rural South African Community-Based MDR-TB Treatment Program 
PLoS ONE  2013;8(5):e64662.
As the South African province of KwaZulu-Natal addresses a growing multidrug-resistant tuberculosis (MDR-TB) epidemic by shifting care and treatment from trained specialty centers to community hospitals, delivering and monitoring MDR-TB therapy has presented new challenges. In particular, tracking and reporting adverse clinical events have been difficult for mobile healthcare workers (HCWs), trained health professionals who travel daily to patient homes to administer and monitor therapy. We designed and piloted a mobile phone application (Mobilize) for mobile HCWs that electronically standardized the recording and tracking of MDR-TB patients on low-cost, functional phones.
We assess the acceptability and feasibility of using Mobilize to record and submit adverse events forms weekly during the intensive phase of MDR-TB therapy and evaluate mobile HCW perceptions throughout the pilot period.
All five mobile HCWs at one site were trained and provided with phones. Utilizing a mixed-methods evaluation, mobile HCWs’ usage patterns were tracked electronically for seven months and analyzed. Qualitative focus groups and questionnaires were designed to understand the impact of mobile phone technology on the work environment.
Mobile HCWs submitted nine of 33 (27%) expected adverse events forms, conflicting with qualitative results in which mobile HCWs stated that Mobilize improved adverse events communication, helped their daily workflow, and could be successfully expanded to other health interventions. When presented with the conflict between their expressed views and actual practice, mobile HCWs cited forgetfulness and believed patients should take more responsibility for their own care.
This pilot experience demonstrated poor uptake by HCWs despite positive responses to using mHealth. Though our results should be interpreted cautiously because of the small number of mobile HCWs and MDR-TB patients in this study, we recommend carefully exploring the motivations of HCWs and technologic enhancements prior to scaling new mHealth initiatives in resource poor settings.
PMCID: PMC3665589  PMID: 23724075
6.  Preterm Birth and Childhood Wheezing Disorders: A Systematic Review and Meta-Analysis 
PLoS Medicine  2014;11(1):e1001596.
In a systematic review and meta-analysis, Jasper Been and colleagues investigate the association between preterm birth and the development of wheezing disorders in childhood.
Please see later in the article for the Editors' Summary
Accumulating evidence implicates early life factors in the aetiology of non-communicable diseases, including asthma/wheezing disorders. We undertook a systematic review investigating risks of asthma/wheezing disorders in children born preterm, including the increasing numbers who, as a result of advances in neonatal care, now survive very preterm birth.
Methods and Findings
Two reviewers independently searched seven online databases for contemporaneous (1 January 1995–23 September 2013) epidemiological studies investigating the association between preterm birth and asthma/wheezing disorders. Additional studies were identified through reference and citation searches, and contacting international experts. Quality appraisal was undertaken using the Effective Public Health Practice Project instrument. We pooled unadjusted and adjusted effect estimates using random-effects meta-analysis, investigated “dose–response” associations, and undertook subgroup, sensitivity, and meta-regression analyses to assess the robustness of associations.
We identified 42 eligible studies from six continents. Twelve were excluded for population overlap, leaving 30 unique studies involving 1,543,639 children. Preterm birth was associated with an increased risk of wheezing disorders in unadjusted (13.7% versus 8.3%; odds ratio [OR] 1.71, 95% CI 1.57–1.87; 26 studies including 1,500,916 children) and adjusted analyses (OR 1.46, 95% CI 1.29–1.65; 17 studies including 874,710 children). The risk was particularly high among children born very preterm (<32 wk gestation; unadjusted: OR 3.00, 95% CI 2.61–3.44; adjusted: OR 2.81, 95% CI 2.55–3.12). Findings were most pronounced for studies with low risk of bias and were consistent across sensitivity analyses. The estimated population-attributable risk of preterm birth for childhood wheezing disorders was ≥3.1%.
Key limitations related to the paucity of data from low- and middle-income countries, and risk of residual confounding.
There is compelling evidence that preterm birth—particularly very preterm birth—increases the risk of asthma. Given the projected global increases in children surviving preterm births, research now needs to focus on understanding underlying mechanisms, and then to translate these insights into the development of preventive interventions.
Review Registration
PROSPERO CRD42013004965
Please see later in the article for the Editors' Summary
Editors' Summary
Most pregnancies last around 40 weeks, but worldwide, more than 11% of babies are born before 37 weeks of gestation (the period during which a baby develops in its mother's womb). Preterm birth is a major cause of infant death—more than 1 million babies die annually from preterm birth complications—and the number of preterm births is increasing globally. Multiple pregnancies, infections, and chronic (long-term) maternal conditions such as diabetes can all cause premature birth, but the cause of many preterm births is unknown. The most obvious immediate complication that is associated with preterm birth is respiratory distress syndrome. This breathing problem, which is more common in early preterm babies than in near-term babies, occurs because the lungs of premature babies are structurally immature and lack pulmonary surfactant, a unique mixture of lipids and proteins that coats the inner lining of the lungs and helps to prevent the collapse of the small air sacs in the lungs that absorb oxygen from the air. Consequently, preterm babies often need help with their breathing and oxygen supplementation.
Why Was This Study Done?
Improvements in the management of prematurity mean that more preterm babies survive today than in the past. However, accumulating evidence suggests that early life events are involved in the subsequent development of non-communicable diseases (non-infectious chronic diseases). Given the increasing burden of preterm birth, a better understanding of the long-term effects of preterm birth is essential. Here, the researchers investigate the risks of asthma and wheezing disorders in children who are born preterm by undertaking a systematic review (a study 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 several studies). Asthma is a chronic condition that is caused by inflammation of the airways. In people with asthma, the airways can react very strongly to allergens such as animal fur and to irritants such as cigarette smoke. Exercise, cold air, and infections can also trigger asthma attacks, which can sometimes be fatal. The symptoms of asthma include wheezing (a high-pitched whistling sound during breathing), coughing, chest tightness, and shortness of breath. Asthma cannot be cured, but drugs can relieve its symptoms and prevent acute asthma attacks.
What Did the Researchers Do and Find?
The researchers identified 30 studies undertaken between 1995 and the present (a time span chosen to allow for recent changes in the management of prematurity) that investigated the association between preterm birth and asthma/wheezing disorders in more than 1.5 million children. Across the studies, 13.7% of preterm babies developed asthma/wheezing disorders during childhood, compared to only 8.3% of babies born at term. Thus, the risk of preterm babies developing asthma or a wheezing disorder during childhood was 1.71 times higher than the risk of term babies developing these conditions (an unadjusted odds ratio [OR] of 1.71). In analyses that allowed for confounding factors—other factors that affect the risk of developing asthma/wheezing disorders such as maternal smoking—the risk of preterm babies developing asthma or a wheezing disorder during childhood was 1.46 times higher than that of babies born at term (an adjusted OR of 1.46). Notably, compared to children born at term, children born very early (before 32 weeks of gestation) had about three times the risk of developing asthma/wheezing disorders in unadjusted and adjusted analyses. Finally, the population-attributable risk of preterm birth for childhood wheezing disorders was more than 3.1%. That is, if no preterm births had occurred, there would have been more than a 3.1% reduction in childhood wheezing disorders.
What Do These Findings Mean?
These findings strongly suggest that preterm birth increases the risk of asthma and wheezing disorders during childhood and that the risk of asthma/wheezing disorders increases as the degree of prematurity increases. The accuracy of these findings may be affected, however, by residual confounding. That is, preterm children may share other, unknown characteristics that increase their risk of developing asthma/wheezing disorders. Moreover, the generalizability of these findings is limited by the lack of data from low- and middle-income countries. However, given the projected global increases in children surviving preterm births, these findings highlight the need to undertake research into the mechanisms underlying the association between preterm birth and asthma/wheezing disorders and the need to develop appropriate preventative and therapeutic measures.
Additional Information
Please access these websites via the online version of this summary at
The March of Dimes, a nonprofit organization for pregnancy and baby health, provides information on preterm birth (in English and Spanish)
Nemours, another nonprofit organization for child health, also provides information (in English and Spanish) on premature babies and on asthma (including personal stories)
The UK National Health Service Choices website provides information about premature labor and birth and a real story about having a preterm baby; it provides information about asthma in children (including real stories)
The MedlinePlus Encyclopedia has pages on preterm birth, asthma, asthma in children, and wheezing (in English and Spanish); MedlinePlus provides links to further information on premature birth, asthma, and asthma in children (in English and Spanish)
PMCID: PMC3904844  PMID: 24492409
7.  Impact of UK Colorectal Cancer Screening Pilot on primary care 
The UK Colorectal Cancer Screening Pilot has recently been completed to evaluate the feasibility of screening using the faecal occult blood test. Screening will be phased in over the next several years, and it is important to consider the impact on the NHS workforce.
To determine the impact of the UK Colorectal Cancer Screening Pilot on primary care workload.
Design of study
A retrospective survey and prospective audit of general practice staff.
General practice.
Workload impact was assessed using a postal questionnaire and a prospective audit of activity in participating practices. Questionnaires were sent to practices that had been involved in the Pilot between 6 weeks and 1 year previously. They were sent to a random sample of 59 practices in Scotland and 60 practices in England between February 2001 and March 2002. Audit forms were sent prospectively to 60 practices involved in the Pilot between May 2001 and September 2002.
Sixty-seven per cent of GPs, 82% of practice managers, 69% of practice nurses, and 70% of receptionists responded to the questionnaire. Of 60 practices contacted to take part in the workload audit, 38 returned completed ‘workload impact audit’ forms. Most practice staff indicated they spent 2% or less of their time during the screening period on Pilot-related activities. Forty per cent of GPs thought that a national colorectal cancer screening programme would substantially impact on the workload in primary care. However, there were variations by country: practice staff in Scotland were more likely to think that it would substantially impact on workload than practice staff in England (44.7% versus 26.6%).
The surveys and audit demonstrate that the Pilot has had a discernible, albeit modest, impact on workload in primary care. Workload of particular significance to primary care personnel includes increases in paperwork, administration, and information provision to patients. The majority of primary care staff support the introduction of a colorectal cancer screening programme. However, there is a strong perception, particularly among GPs, that a national programme of faecal occult blood test screening will impact significantly on workload in primary care, and that primary care-based activities generated through screening should be adequately resourced and remunerated.
PMCID: PMC1266238  PMID: 15667761
cancer screening; primary health care; workload; evaluation
8.  Clinical and functional characteristics of patients two years after being affected by the soybean asthma epidemic in Barcelona. 
Thorax  1994;49(9):906-909.
BACKGROUND--Patients affected during the asthma outbreaks caused by soybean dust inhalation in Barcelona presented with sudden onset of severe asthma followed by the rapid relief of symptoms after treatment. Two years after the epidemics ended, a case-control study was conducted in which the clinical, functional, and immunological characteristics of these asthma patients (a randomised sample of asthmatic patients admitted as emergency cases on epidemic days, n = 213) were compared with those of a control group (a random sample of asthmatic patients admitted as emergency cases for attacks of asthma on non-epidemic days, n = 170). METHODS--The study included the administration of the ATS-DLD78 standardised respiratory questionnaire, the measurement of atopy, and performance of spirometric tests and a methacholine inhalation test. RESULTS--Patients with epidemic asthma reported fewer symptoms of asthma, had attended emergency departments less frequently during the previous year for acute attacks of asthma, were taking fewer inhaled corticosteroids at the time of the study, and attended medical follow up less frequently than did the patients with non-epidemic asthma. However, the cases and controls showed no differences in ventilatory capacity or reactivity to the methacholine bronchoprovocation test. CONCLUSIONS--Two years after the end of the soybean epidemics, people affected by epidemic asthma had a favourable prognosis. This finding contrasts with a higher risk of life threatening asthma and death during the epidemics. This paradox could be the result of a complex interaction between host and conditions of exposure.
PMCID: PMC475189  PMID: 7940432
9.  Tiotropium in asthma: a systematic review 
The objective of this paper is to systematically review the existing evidence of the effectiveness and safety profile of a long-acting inhaled muscarinic antagonist as add-on therapy in patients with asthma that is uncontrolled despite inhaled corticosteroid (ICS) use.
With the assistance of two experienced research librarians, we searched Ovid MEDLINE/PubMed (1946 to September 12, 2013), the Cochrane Library review, and the TRIP database. The key search terms were “tiotropium and asthma.” The search was limited to human data published in English. Included in the systematic review were all randomized controlled trials that evaluated the efficacy of tiotropium in patients with asthma. The clinical trials had to be at least 4 weeks in duration and to provide adequate information on clinically appropriate end points in asthma care (eg, change in lung function, exacerbation rates, and/or ICS dosing). Data on patient characteristics, study design, outcome measures, concomitant asthma medication, and adverse events were extracted from the full text of each included individual study. Marked heterogeneity of study design precluded statistical pooling of results for a meta-analysis. Consequently, only descriptive summaries of outcomes are provided.
Our database search retrieved 149 citations. We found five randomized controlled trials in humans that met our criteria for inclusion in the systematic review. We also found two open-label uncontrolled trials that were considered in the discussion. Each of the five included studies met the Consolidated Standards of Reporting Trials criteria for a well-designed randomized trial.
The five clinical studies included in this systematic review focused on evaluating the efficacy of tiotropium as add-on therapy to ICS or ICS in combination with a long-acting inhaled β2-agonist (LABA) in patients with uncontrolled moderate to severe persistent asthma. Tiotropium maintained lung function when ICSs were tapered and when an LABA was discontinued. Tiotropium improved lung function when added to ICS alone or ICS–LABA combination therapy. In the only trial to have compared the addition of tiotropium with doubling the dose of ICS, tiotropium provided significantly superior results. In trials in which the addition of tiotropium was compared with salmeterol, the beneficial effects of these two bronchodilators were similar. No safety concerns were found with use of tiotropium as add-on therapy.
Tiotropium may have a beneficial role in moderate to severe persistent asthma despite use of an ICS or ICS and LABA. Use of tiotropium as add-on therapy poses no safety concerns.
PMCID: PMC3942115  PMID: 24600237
tiotropium; asthma; lung; inflammation; inhaled corticosteroid; LABA; LAMA
10.  Using GPS Technology to Quantify Human Mobility, Dynamic Contacts and Infectious Disease Dynamics in a Resource-Poor Urban Environment 
PLoS ONE  2013;8(4):e58802.
Empiric quantification of human mobility patterns is paramount for better urban planning, understanding social network structure and responding to infectious disease threats, especially in light of rapid growth in urbanization and globalization. This need is of particular relevance for developing countries, since they host the majority of the global urban population and are disproportionally affected by the burden of disease. We used Global Positioning System (GPS) data-loggers to track the fine-scale (within city) mobility patterns of 582 residents from two neighborhoods from the city of Iquitos, Peru. We used ∼2.3 million GPS data-points to quantify age-specific mobility parameters and dynamic co-location networks among all tracked individuals. Geographic space significantly affected human mobility, giving rise to highly local mobility kernels. Most (∼80%) movements occurred within 1 km of an individual’s home. Potential hourly contacts among individuals were highly irregular and temporally unstructured. Only up to 38% of the tracked participants showed a regular and predictable mobility routine, a sharp contrast to the situation in the developed world. As a case study, we quantified the impact of spatially and temporally unstructured routines on the dynamics of transmission of an influenza-like pathogen within an Iquitos neighborhood. Temporally unstructured daily routines (e.g., not dominated by a single location, such as a workplace, where an individual repeatedly spent significant amount of time) increased an epidemic’s final size and effective reproduction number by 20% in comparison to scenarios modeling temporally structured contacts. Our findings provide a mechanistic description of the basic rules that shape human mobility within a resource-poor urban center, and contribute to the understanding of the role of fine-scale patterns of individual movement and co-location in infectious disease dynamics. More generally, this study emphasizes the need for careful consideration of human social interactions when designing infectious disease mitigation strategies, particularly within resource-poor urban environments.
PMCID: PMC3620113  PMID: 23577059
11.  The Relationship between Asthma and Obesity in Urban Early Adolescents 
Asthma and obesity, which have reached epidemic proportions, impact urban youth to a great extent. Findings are inconsistent regarding their relationship; no studies have considered asthma management. We explored the association of obesity and asthma-related morbidity, asthma-related health care utilization, and asthma management in urban adolescents with uncontrolled asthma. We classified 373 early adolescents (mean age=12.8 years; 82% Hispanic or Black) from New York City public middle schools into 4 weight categories: normal (body mass index [BMI]<85th percentile); overweight (85th percentile≤BMI<95th percentile); obese (95th percentile≤BMI<97th percentile); and very obese (BMI≥97th percentile). We compared sample obesity prevalence to national estimates, and tested whether weight categories predicted caregiver reported asthma outcomes, adjusting for age and race/ethnicity. Obesity prevalence was 37%, with 28% of the sample being very obese; both rates were significantly higher than national estimates. We found no significant differences in asthma-related health care utilization or asthma management between weight categories, and a few differences in asthma-related morbidity. Relative to normal weight and obese youth, overweight youth had higher odds of never having any days with asthma-related activity limitations. They also had higher odds of never having asthma-related school absences compared with obese youth. Overweight youth with asthma-related activity limitations had more days with limitations compared with normal weight youth. Overweight, but not obese youth, missed more school due to asthma than normal weight youth. Overweight and obesity prevalence was very high in urban, Hispanic, and Black adolescents with uncontrolled asthma, but not strongly associated with asthma-related morbidity, asthma-related health care utilization, or asthma management practices.
PMCID: PMC3429276  PMID: 22970423
12.  Assessing Optimal Target Populations for Influenza Vaccination Programmes: An Evidence Synthesis and Modelling Study 
PLoS Medicine  2013;10(10):e1001527.
Marc Baguelin and colleagues use virological, clinical, epidemiological, and behavioral data to estimate how policies for influenza vaccination programs may be optimized in England and Wales.
Please see later in the article for the Editors' Summary
Influenza vaccine policies that maximise health benefit through efficient use of limited resources are needed. Generally, influenza vaccination programmes have targeted individuals 65 y and over and those at risk, according to World Health Organization recommendations. We developed methods to synthesise the multiplicity of surveillance datasets in order to evaluate how changing target populations in the seasonal vaccination programme would affect infection rate and mortality.
Methods and Findings
Using a contemporary evidence-synthesis approach, we use virological, clinical, epidemiological, and behavioural data to develop an age- and risk-stratified transmission model that reproduces the strain-specific behaviour of influenza over 14 seasons in England and Wales, having accounted for the vaccination uptake over this period. We estimate the reduction in infections and deaths achieved by the historical programme compared with no vaccination, and the reduction had different policies been in place over the period. We find that the current programme has averted 0.39 (95% credible interval 0.34–0.45) infections per dose of vaccine and 1.74 (1.16–3.02) deaths per 1,000 doses. Targeting transmitters by extending the current programme to 5–16-y-old children would increase the efficiency of the total programme, resulting in an overall reduction of 0.70 (0.52–0.81) infections per dose and 1.95 (1.28–3.39) deaths per 1,000 doses. In comparison, choosing the next group most at risk (50–64-y-olds) would prevent only 0.43 (0.35–0.52) infections per dose and 1.77 (1.15–3.14) deaths per 1,000 doses.
This study proposes a framework to integrate influenza surveillance data into transmission models. Application to data from England and Wales confirms the role of children as key infection spreaders. The most efficient use of vaccine to reduce overall influenza morbidity and mortality is thus to target children in addition to older adults.
Please see later in the article for the Editors' Summary
Editors' Summary
Every winter, millions of people catch influenza, a viral infection of the airways. Most infected individuals recover quickly, but seasonal influenza outbreaks (epidemics) kill about half a million people annually. In countries with advanced health systems, these deaths occur mainly among elderly people and among individuals with long-term illnesses such as asthma and heart disease that increase the risk of complications occurring after influenza virus infection. Epidemics of influenza occur because small but frequent changes in the influenza virus mean that an immune response produced one year through infection provides only partial protection against influenza the following year. Annual immunization with a vaccine that contains killed influenza viruses of the major circulating strains can greatly reduce a person's risk of catching influenza by preparing the immune system to respond quickly when challenged by a live influenza virus. Consequently, many countries run seasonal influenza vaccination programs that, in line with World Health Organization recommendations, target individuals 65 years old and older and people in high-risk groups.
Why Was This Study Done?
Is this approach the best use of available resources? Might, for example, vaccination of children—the main transmitters of influenza—provide more benefit to the whole population than vaccination of elderly people? Vaccination of children would not directly prevent as many influenza-related deaths as vaccination of elderly people, but it might indirectly prevent deaths in elderly adults by inducing herd immunity—vaccination of a large part of a population can protect unvaccinated members of the population by reducing the chances of an infection spreading. Policy makers need to know whether a change to an influenza vaccination program is likely to provide additional population benefits before altering the program. In this evidence synthesis and modeling study, the researchers combine (synthesize) longitudinal influenza surveillance datasets (data collected over time) from England and Wales, develop a mathematical model for influenza transmission based on these data using a Bayesian statistical approach, and use the model to evaluate the impact on influenza infections and deaths of changes to the seasonal influenza vaccination program in England and Wales.
What Did the Researchers Do and Find?
The researchers developed an influenza transmission model using clinical data on influenza-like illness consultations collected in a primary care surveillance scheme for each week of 14 influenza seasons in England and Wales, virological information on respiratory viruses detected in a subset of patients presenting with clinically suspected influenza, and data on vaccination coverage in the whole population (epidemiological data). They also incorporated data on social contacts (behavioral data) and on immunity to influenza viruses in the population (seroepidemiological data) into their model. To estimate the impact of potential changes to the current vaccination strategy in England and Wales, the researchers used their model, which replicated the patterns of disease observed in the surveillance data, to run simulated epidemics for each influenza season and for three strains of influenza virus under various vaccination scenarios. Compared to no vaccination, the current program (vaccination of people 65 years old and older and people in high-risk groups) averted 0.39 infections per dose of vaccine and 1.74 deaths per 1,000 doses. Notably, the model predicted that extension of the program to target 5–16-year-old children would increase the efficiency of the program and would avert 0.70 infections per dose and 1.95 deaths per 1,000 doses.
What Do These Findings Mean?
The finding that the transmission model developed by the researchers closely fit the available surveillance data suggests that the model should be able to predict what would have happened in England and Wales over the study period if an alternative vaccination regimen had been in place. The accuracy of such predictions may be limited, however, because the vaccination model is based on a series of simplifying assumptions. Importantly, given that influenza vaccination for children is being rolled out in England and Wales from September 2013, the model confirms that children are key spreaders of influenza and suggests that a vaccination program targeting children will reduce influenza infections and potentially influenza deaths in the whole population. More generally, the findings of this study support wider adoption of national vaccination strategies designed to block influenza transmission and to target those individuals most at risk from the complications of influenza infection.
Additional Information
Please access these websites via the online version of this summary at
The UK National Health Service Choices website provides information for patients about seasonal influenza and about vaccination; Public Health England (formerly the Health Protection Agency) provides information on influenza surveillance in the UK, including information about the primary care surveillance database used in this study
The World Health Organization provides information on seasonal influenza (in several languages)
The European Influenzanet is a system to monitor the activity of influenza-like illness with the aid of volunteers via the Internet
The US Centers for Disease Control and Prevention also provides information for patients and health professionals on all aspects of seasonal influenza, including information about vaccination and about the US influenza surveillance system; its website contains a short video about personal experiences of influenza, a US government website, provides access to information on seasonal influenza and vaccination
MedlinePlus has links to further information about influenza and about immunization (in English and Spanish)
PMCID: PMC3793005  PMID: 24115913
13.  Inferring Epidemic Contact Structure from Phylogenetic Trees 
PLoS Computational Biology  2012;8(3):e1002413.
Contact structure is believed to have a large impact on epidemic spreading and consequently using networks to model such contact structure continues to gain interest in epidemiology. However, detailed knowledge of the exact contact structure underlying real epidemics is limited. Here we address the question whether the structure of the contact network leaves a detectable genetic fingerprint in the pathogen population. To this end we compare phylogenies generated by disease outbreaks in simulated populations with different types of contact networks. We find that the shape of these phylogenies strongly depends on contact structure. In particular, measures of tree imbalance allow us to quantify to what extent the contact structure underlying an epidemic deviates from a null model contact network and illustrate this in the case of random mixing. Using a phylogeny from the Swiss HIV epidemic, we show that this epidemic has a significantly more unbalanced tree than would be expected from random mixing.
Author Summary
One of the recent key innovations in the epidemiology of infectious diseases was the incorporation of explicit contact structure (i.e. who can infect whom) into epidemiological models. Theoretical studies have generated a broad consensus in the field that knowledge of the contact network may help to greatly improve the control of the spread of epidemics. The key problem in the field, however, is that we lack knowledge regarding the actual contact structure underlying real epidemics. Much research is focused on trying to reconstruct actual contact networks in various ways (mobile phone usage data, electronic devices that measure physical proximity, patient interviews, etc). All of these approaches are highly labour intensive and are fraught with many difficulties. Here, we present a new approach which is based on readily available sequence data. Using the Swiss HIV epidemic as an example, we show that it displays strong indications of a underlying contact structure that strongly differs from random interactions, thus undercutting the assumption of random mixing which is commonly made in epidemiological models.
PMCID: PMC3297558  PMID: 22412361
14.  A Randomized trial of an Asthma Internet Self-management Intervention (RAISIN): study protocol for a randomized controlled trial 
Trials  2014;15:185.
The financial costs associated with asthma care continue to increase while care remains suboptimal. Promoting optimal self-management, including the use of asthma action plans, along with regular health professional review has been shown to be an effective strategy and is recommended in asthma guidelines internationally. Despite evidence of benefit, guided self-management remains underused, however the potential for online resources to promote self-management behaviors is gaining increasing recognition. The aim of this paper is to describe the protocol for a pilot evaluation of a website ‘Living well with asthma’ which has been developed with the aim of promoting self-management behaviors shown to improve outcomes.
The study is a parallel randomized controlled trial, where adults with asthma are randomly assigned to either access to the website for 12 weeks, or usual asthma care for 12 weeks (followed by access to the website if desired). Individuals are included if they are over 16-years-old, have a diagnosis of asthma with an Asthma Control Questionnaire (ACQ) score of greater than, or equal to 1, and have access to the internet. Primary outcomes for this evaluation include recruitment and retention rates, changes at 12 weeks from baseline for both ACQ and Asthma Quality of Life Questionnaire (AQLQ) scores, and quantitative data describing website usage (number of times logged on, length of time logged on, number of times individual pages looked at, and for how long). Secondary outcomes include clinical outcomes (medication use, health services use, lung function) and patient reported outcomes (including adherence, patient activation measures, and health status).
Piloting of complex interventions is considered best practice and will maximise the potential of any future large-scale randomized controlled trial to successfully recruit and be able to report on necessary outcomes. Here we will provide results across a range of outcomes which will provide estimates of efficacy to inform the design of a future full-scale randomized controlled trial of the ‘Living well with asthma’ website.
Trial registration
This trial is registered with Current Controlled Trials ISRCTN78556552 on 18/06/13.
PMCID: PMC4055289  PMID: 24884722
Asthma; Self-management; Adherence; E-health; Randomized controlled trial; Complex intervention; Inhaled corticosteroids; Behaviour change
15.  Multidisciplinary approach to management of maternal asthma (MAMMA [copyright]): the PROTOCOL for a randomized controlled trial 
BMC Public Health  2012;12:1094.
Uncontrolled asthma during pregnancy is associated with the maternal hazards of disease exacerbation, and perinatal hazards including intrauterine growth restriction and preterm birth. Interventions directed at achieving better asthma control during pregnancy should be considered a high priority in order to optimise both maternal and perinatal outcomes. Poor compliance with prescribed asthma medications during pregnancy and suboptimal prescribing patterns to pregnant women have both been shown to be contributing factors that jeopardise asthma control. The aim is to design and evaluate an intervention involving multidisciplinary care for women experiencing asthma in pregnancy.
A pilot single-blinded parallel-group randomized controlled trial testing a Multidisciplinary Approach to Management of Maternal Asthma (MAMMA©) which involves education and regular monitoring. Pregnant women with asthma will be recruited from antenatal clinics in Victoria, Australia. Recruited participants, stratified by disease severity, will be allocated to the intervention or the usual care group in a 1:1 ratio. Both groups will be followed prospectively throughout pregnancy and outcomes will be compared between groups at three and six months after recruitment to evaluate the effectiveness of this intervention. Outcome measures include Asthma Control Questionnaire (ACQ) scores, oral corticosteroid use, asthma exacerbations and asthma related hospital admissions, and days off work, preventer to reliever ratio, along with pregnancy and neonatal adverse events at delivery. The use of FEV1/FEV6 will be also investigated during this trial as a marker for asthma control.
If successful, this model of care could be widely implemented in clinical practice and justify more funding for support services and resources for these women. This intervention will also promote awareness of the risks of poorly controlled asthma and the need for a collaborative, multidisciplinary approach to asthma management during pregnancy. This is also the first study to investigate the use of FEV1/FEV6 as a marker for asthma control during pregnancy.
Trial registration
Australian New Zealand Clinical Trials Registry (ACTRN12612000681853)
PMCID: PMC3536559  PMID: 23253481
Asthma; Pregnancy; Inhaled corticosteroids; Randomized controlled trial; Antenatal care; Intervention; Lung function tests; Multidisciplinary care
16.  Preventing and lessening exacerbations of asthma in school-age children associated with a new term (PLEASANT): study protocol for a cluster randomised control trial 
Trials  2013;14:297.
Within the UK, during September, there is a pronounced increase in the number of unscheduled medical contacts by school-aged children (4–16 years) with asthma. It is thought that that this might be caused by the return back to school after the summer holidays, suddenly mixing with other children again and picking up viruses which could affect their asthma. There is also a drop in the number of prescriptions administered in August. It is possible therefore that children might not be taking their medication as they should during the summer contributing to them becoming ill when they return to school.
It is hoped that a simple intervention from the GP to parents of children with asthma at the start of the summer holiday period, highlighting the importance of maintaining asthma medication can help prevent increased asthma exacerbation, and unscheduled NHS appointments, following return to school in September.
PLEASANT is a cluster randomised trial. A total of 140 General Practices (GPs) will be recruited into the trial; 70 GPs randomised to the intervention and 70 control practices of “usual care”. An average practice is expected to have approximately 100 children (aged 4–16 with a diagnosis of asthma) hence observational data will be collected on around 14000 children over a 24-month period. The Clinical Practice Research Datalink will collect all data required for the study which includes diagnostic, prescription and referral data.
The trial will assess whether the intervention can reduce exacerbation of asthma and unscheduled medical contacts in school-aged children associated with the return to school after the summer holidays. It has the potential to benefit the health and quality of life of children with asthma while also improving the effectiveness of NHS services by reducing NHS use in one of the busiest months of the year.
An exploratory health economic analysis will gauge any cost saving associated with the intervention and subsequent impacts on quality of life. If results for the intervention are positive it is hoped that this could be adopted as part of routine care management of childhood asthma in general practice.
Trial registration
Current controlled trials: ISRCTN03000938 (assigned 19/10/12)
UKCRN ID: 13572
PMCID: PMC4016495  PMID: 24041259
Asthma; Childhood asthma; Asthma exacerbation; Cluster randomised controlled trial; Primary care; Public health intervention; Unscheduled medical appointments
17.  Assessing Adolescent Asthma Symptoms and Adherence Using Mobile Phones 
Self-report is the most common method of measuring medication adherence but is influenced by recall error and response bias, and it typically does not provide insight into the causes of poor adherence. Ecological momentary assessment (EMA) of health behaviors using mobile phones offers a promising alternative to assessing adherence and collecting related data that can be clinically useful for adherence problem solving.
To determine the feasibility of using EMA via mobile phones to assess adolescent asthma medication adherence and identify contextual characteristics of adherence decision making.
We utilized a descriptive and correlational study design to explore a mobile method of symptom and adherence assessment using an interactive voice response system. Adolescents aged 12-18 years with a diagnosis of asthma and prescribed inhalers were recruited from an academic medical center. A survey including barriers to mobile phone use, the Illness Management Survey, and the Pediatric Asthma Quality of Life Questionnaire were administered at baseline. Quantitative and qualitative assessment of asthma symptoms and adherence were conducted with daily calls to mobile phones for 1 month. The Asthma Control Test (ACT) was administered at 2 study time points: baseline and 1 month after baseline.
The sample consisted of 53 adolescents who were primarily African American (34/53, 64%) and female (31/53, 58%) with incomes US$40K/year or lower (29/53, 55%). The majority of adolescents (37/53, 70%) reported that they carried their phones with them everywhere, but only 47% (25/53) were able to use their mobile phone at school. Adolescents responded to an average of 20.1 (SD 8.1) of the 30 daily calls received (67%). Response frequency declined during the last week of the month (b=-0.29, P<.001) and was related to EMA-reported levels of rescue inhaler adherence (r= 0.33, P=.035). Using EMA, adolescents reported an average of 0.63 (SD 1.2) asthma symptoms per day and used a rescue inhaler an average of 70% of the time (SD 35%) when they experienced symptoms. About half (26/49, 53%) of the instances of nonadherence took place in the presence of friends. The EMA-measured adherence to rescue inhaler use correlated appropriately with asthma control as measured by the ACT (r=-0.33, P=.034).
Mobile phones provided a feasible method to assess asthma symptoms and adherence in adolescents. The EMA method was consistent with the ACT, a widely established measure of asthma control, and results provided valuable insights regarding the context of adherence decision making that could be used clinically for problem solving or as feedback to adolescents in a mobile or Web-based support system.
PMCID: PMC3785951  PMID: 23864345
asthma; adherence; mobile technology; adolescent; assessment
18.  527 Evaluation of the September Epidemic of Asthma Exacerbation in Children in Our Practice 
Know that the rate of asthma exacerbations are increased in September after summer vacation with the beginning of school year. Investigators have been studied this problem and it was supposed that the main cause could be the stress associated with school return what can worsen asthma symptoms. Beside this children returning to school after summer vacation are reexposed to respiratory viral infections, sensitizing allergens in the school enviroment, and can be connected with poor compliance in the medication in the summer period.
We stared to investigate that what could be the causative factors in children who suffered dyspnoe and other signs of asthmatic exacerbation from September 2008, could we present the increasing number of these patients in hospitalization rate, and could we confirm the changing compliance of the regular medication during the summer period? A short questionaire was constructed and was given the patients who were admitted to hospital (162) with asthma exacerbation symptoms. Then 45 patients were selected for a longer follow up to investigate their compliance in medication. We investigate from the database of our Hospital the asthmatic patient's admission rate from 2006.
We could present from 2006 the increasing number of patients admitted because of asthma exacerbation in September in every year. We could present the increased number of schoolage patient among all of the admitted patients in the fall season. We compared the genders which were similar. We found that the symptom of asthma was worse in the fall season. We confirmed the higher number of patients suffering from viral infections. But the changing rate among patient who stopped the medication during summer was low as 13%.
We could confirm the September epidemic of asthma exacerbation among our patients as well. Compare the international investigations the main cause of the September epidemic of asthma connecting with the beginning of the school year and the increasing number of viral infections at this period of the year. Fortunately our patient compliance was good but we have to continue our patients’ education from time to time.
PMCID: PMC3512688
19.  Towards Universal Voluntary HIV Testing and Counselling: A Systematic Review and Meta-Analysis of Community-Based Approaches 
PLoS Medicine  2013;10(8):e1001496.
In a systematic review and meta-analysis, Amitabh Suthar and colleagues describe the evidence base for different HIV testing and counseling services provided outside of health facilities.
Please see later in the article for the Editors' Summary
Effective national and global HIV responses require a significant expansion of HIV testing and counselling (HTC) to expand access to prevention and care. Facility-based HTC, while essential, is unlikely to meet national and global targets on its own. This article systematically reviews the evidence for community-based HTC.
Methods and Findings
PubMed was searched on 4 March 2013, clinical trial registries were searched on 3 September 2012, and Embase and the World Health Organization Global Index Medicus were searched on 10 April 2012 for studies including community-based HTC (i.e., HTC outside of health facilities). Randomised controlled trials, and observational studies were eligible if they included a community-based testing approach and reported one or more of the following outcomes: uptake, proportion receiving their first HIV test, CD4 value at diagnosis, linkage to care, HIV positivity rate, HTC coverage, HIV incidence, or cost per person tested (outcomes are defined fully in the text). The following community-based HTC approaches were reviewed: (1) door-to-door testing (systematically offering HTC to homes in a catchment area), (2) mobile testing for the general population (offering HTC via a mobile HTC service), (3) index testing (offering HTC to household members of people with HIV and persons who may have been exposed to HIV), (4) mobile testing for men who have sex with men, (5) mobile testing for people who inject drugs, (6) mobile testing for female sex workers, (7) mobile testing for adolescents, (8) self-testing, (9) workplace HTC, (10) church-based HTC, and (11) school-based HTC. The Newcastle-Ottawa Quality Assessment Scale and the Cochrane Collaboration's “risk of bias” tool were used to assess the risk of bias in studies with a comparator arm included in pooled estimates.
 117 studies, including 864,651 participants completing HTC, met the inclusion criteria. The percentage of people offered community-based HTC who accepted HTC was as follows: index testing, 88% of 12,052 participants; self-testing, 87% of 1,839 participants; mobile testing, 87% of 79,475 participants; door-to-door testing, 80% of 555,267 participants; workplace testing, 67% of 62,406 participants; and school-based testing, 62% of 2,593 participants. Mobile HTC uptake among key populations (men who have sex with men, people who inject drugs, female sex workers, and adolescents) ranged from 9% to 100% (among 41,110 participants across studies), with heterogeneity related to how testing was offered. Community-based approaches increased HTC uptake (relative risk [RR] 10.65, 95% confidence interval [CI] 6.27–18.08), the proportion of first-time testers (RR 1.23, 95% CI 1.06–1.42), and the proportion of participants with CD4 counts above 350 cells/µl (RR 1.42, 95% CI 1.16–1.74), and obtained a lower positivity rate (RR 0.59, 95% CI 0.37–0.96), relative to facility-based approaches. 80% (95% CI 75%–85%) of 5,832 community-based HTC participants obtained a CD4 measurement following HIV diagnosis, and 73% (95% CI 61%–85%) of 527 community-based HTC participants initiated antiretroviral therapy following a CD4 measurement indicating eligibility. The data on linking participants without HIV to prevention services were limited. In low- and middle-income countries, the cost per person tested ranged from US$2–US$126. At the population level, community-based HTC increased HTC coverage (RR 7.07, 95% CI 3.52–14.22) and reduced HIV incidence (RR 0.86, 95% CI 0.73–1.02), although the incidence reduction lacked statistical significance. No studies reported any harm arising as a result of having been tested.
Community-based HTC achieved high rates of HTC uptake, reached people with high CD4 counts, and linked people to care. It also obtained a lower HIV positivity rate relative to facility-based approaches. Further research is needed to further improve acceptability of community-based HTC for key populations. HIV programmes should offer community-based HTC linked to prevention and care, in addition to facility-based HTC, to support increased access to HIV prevention, care, and treatment.
Review Registration
International Prospective Register of Systematic Reviews CRD42012002554
Please see later in the article for the Editors' Summary
Editors' Summary
Three decades into the AIDS epidemic, about 34 million people (most living in resource-limited countries) are infected with HIV, the virus that causes AIDS. Every year another 2.2 million people become infected with HIV, usually through unprotected sex with an infected partner, and about 1.7 million people die. Infection with HIV, which gradually destroys the CD4 lymphocytes and other immune system cells that provide protection from life-threatening infections, is usually diagnosed by looking for antibodies to HIV in the blood or saliva. Disease progression is subsequently monitored in HIV-positive individuals by counting the CD4 cells in their blood. Initiation of antiretroviral drug therapy—a combination of drugs that keeps HIV replication in check but that does not cure the infection—is recommended when an individual's CD4 count falls below 500 cells/µl of blood or when he or she develops signs of severe or advanced disease, such as unusual infections.
Why Was This Study Done?
As part of intensified efforts to eliminate HIV/AIDS, United Nations member states recently set several HIV-related targets to be achieved by 2015, including reduced transmission of HIV and increased delivery of antiretroviral therapy. These targets can only be achieved if there is a large expansion in HIV testing and counseling (HTC) and increased access to HIV prevention and care services. The World Health Organization currently recommends that everyone attending a healthcare facility in regions where there is a generalized HIV epidemic (defined as when 1% or more of the general population is HIV-positive) should be offered HTC. However, many people rarely visit healthcare facilities, and others refuse “facility-based” HTC because they fear stigmatization and discrimination. Thus, facility-based HTC alone is unlikely to be sufficient to enable national and global HIV targets to be reached. In this systematic review and meta-analysis, the researchers evaluate the performance of community-based HTC approaches such as index testing (offering HTC to the sexual and injecting partners and household members of people with HIV), mobile testing (offering HTC through a service that visits shopping centers and other public facilities), and door-to-door testing (systematically offering HTC to homes in a catchment area). A systematic review uses predefined criteria to identify all the research on a given topic; meta-analysis combines the results of several studies.
What Did the Researchers Do and Find?
The researchers identified 117 studies (most undertaken in Africa and North America) involving 864,651 participants that evaluated community-based HTC approaches. Among these studies, the percentage of people offered community-based HTC who accepted it (HTC uptake) was 88% for index testing, 87% for self-testing, 80% for door-to-door testing, 67% for workplace testing, and 62% for school-based testing. Compared to facility-based approaches, community-based approaches increased the chances of an individual's CD4 count being above 350 cells/µl at diagnosis (an important observation because early diagnosis improves subsequent outcomes) but had a lower positivity rate, possibly because people with symptoms of HIV are more likely to visit healthcare facilities than healthy individuals. Importantly, 80% of participants in the community-based HTC studies had their CD4 count measured after HIV diagnosis, and 73% of the participants initiated antiretroviral therapy after their CD4 count fell below national eligibility criteria; both these observations suggest that community-based HTC successfully linked people to care. Finally, offering community-based HTC approaches in addition to facility-based approaches increased HTC coverage seven-fold at the population level.
What Do These Findings Mean?
These findings show that community-based HTC can achieve high HTC uptake rates and can reach HIV-positive individuals earlier, when they still have high CD4 counts. Importantly, they also suggest that the level of linkage to care of community-based HTC is similar to that of facility-based HTC. Although the lower positivity rate of community-based HTC approaches means that more people need to be tested with these approaches than with facility-based HTC to identify the same number of HIV-positive individuals, this downside of community-based HTC is likely to be offset by the earlier identification of HIV-positive individuals, which should improve life expectancy and reduce HIV transmission at the population level. Although further studies are needed to evaluate community-based HTC in other regions of the world, these findings suggest that offering community-based HTC in HIV programs in addition to facility-based testing should support the increased access to HIV prevention and care that is required for the intensification of HIV/AIDS elimination efforts.
Additional Information
Please access these websites via the online version of this summary at
The World Health Organization provides information on all aspects of HIV/AIDS, including information on counseling and testing (in several languages)
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 the global HIV/AIDS epidemic, on HIV testing, and on HIV transmission and testing (in English and Spanish)
The UK National Health Service Choices website provides information (including personal stories) about HIV and AIDS
The World AIDS Day Report 2012 provides up-to-date information about the AIDS epidemic and efforts to halt it
Patient stories about living with HIV/AIDS are available through Avert; the nonprofit website Healthtalkonline also provides personal stories about living with HIV, including stories about getting a diagnosis
PMCID: PMC3742447  PMID: 23966838
20.  Elimination of HIV in South Africa through Expanded Access to Antiretroviral Therapy: A Model Comparison Study 
PLoS Medicine  2013;10(10):e1001534.
Using nine structurally different models, Jan Hontelez and colleagues investigate timeframes for HIV elimination in South Africa using a universal test and treat strategy.
Please see later in the article for the Editors' Summary
Expanded access to antiretroviral therapy (ART) using universal test and treat (UTT) has been suggested as a strategy to eliminate HIV in South Africa within 7 y based on an influential mathematical modeling study. However, the underlying deterministic model was criticized widely, and other modeling studies did not always confirm the study's finding. The objective of our study is to better understand the implications of different model structures and assumptions, so as to arrive at the best possible predictions of the long-term impact of UTT and the possibility of elimination of HIV.
Methods and Findings
We developed nine structurally different mathematical models of the South African HIV epidemic in a stepwise approach of increasing complexity and realism. The simplest model resembles the initial deterministic model, while the most comprehensive model is the stochastic microsimulation model STDSIM, which includes sexual networks and HIV stages with different degrees of infectiousness. We defined UTT as annual screening and immediate ART for all HIV-infected adults, starting at 13% in January 2012 and scaled up to 90% coverage by January 2019. All models predict elimination, yet those that capture more processes underlying the HIV transmission dynamics predict elimination at a later point in time, after 20 to 25 y. Importantly, the most comprehensive model predicts that the current strategy of ART at CD4 count ≤350 cells/µl will also lead to elimination, albeit 10 y later compared to UTT. Still, UTT remains cost-effective, as many additional life-years would be saved. The study's major limitations are that elimination was defined as incidence below 1/1,000 person-years rather than 0% prevalence, and drug resistance was not modeled.
Our results confirm previous predictions that the HIV epidemic in South Africa can be eliminated through universal testing and immediate treatment at 90% coverage. However, more realistic models show that elimination is likely to occur at a much later point in time than the initial model suggested. Also, UTT is a cost-effective intervention, but less cost-effective than previously predicted because the current South African ART treatment policy alone could already drive HIV into elimination.
Please see later in the article for the Editors' Summary
Editors' Summary
About 34 million people (mostly in low- and middle-income countries) are currently infected with HIV, the virus that causes AIDS, and every year another 2.5 million people become infected. HIV, which is usually transmitted through unprotected sex with an infected partner, gradually destroys CD4 lymphocytes and other immune system cells, leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, people infected with HIV often died within ten years of infection. Then, in 1996, antiretroviral therapy (ART) became available, and, for people living in affluent countries, HIV/AIDS became a chronic condition. However, ART was expensive, so HIV/AIDS remained a fatal condition for people living in resource-limited countries. In 2006, the international community set a target of achieving universal ART coverage by 2010, and ART programs were initiated in many resource-limited countries. Although universal ART coverage has still not been achieved in South Africa, where nearly 6 million people are HIV-positive, 80% of people in need of ART were receiving a World Health Organization–recommended ART regimen by October 2012.
Why Was This Study Done?
ART is usually started when a person's CD4 count falls below 350 cells/µl blood, but it is thought that treatment of all HIV-positive individuals, regardless of their CD4 count, could reduce HIV transmission by reducing the infectiousness of HIV-positive individuals (“treatment as prevention”). Might it be possible, therefore, to eliminate HIV by screening everyone annually for infection and treating all HIV-positive individuals immediately? In 2009, a mathematical modeling study suggested that seven years of universal test and treat (UTT) could eliminate HIV in South Africa. The deterministic (nonrandom) model used in that study has been widely criticized, however, and some subsequent modeling studies have reached different conclusions, probably because of differences in the models' structures and in the assumptions built into them. A better understanding of the reasons for the discrepancies between models would help policy-makers decide whether to introduce UTT, so, here, the researchers developed several increasingly complex and realistic models of the South African HIV epidemic and used these models to predict the long-term impact of UTT in South Africa.
What Did the Researchers Do and Find?
The researchers developed nine structurally different mathematical models of the South African HIV epidemic based on the STDSIM framework, a stochastic microsimulation model that simulates the life course of individuals in a dynamic network of sexual contacts and in which events such as HIV infection are random processes. The simplest model, which resembled the original deterministic model, was extended by sequentially adding in factors such as different HIV transmission rates at different stages of HIV infection and up-to-date assumptions regarding the ability of ART to reduce HIV infectiousness. All the models replicated the prevalence of HIV in South Africa (the proportion of the population that was HIV-positive) between 1990 and 2010, and all predicted that UTT (defined as annual screening of individuals age 15+ years and immediate ART for all HIV-infected adults starting in 2012 and scaled up to 90% coverage by 2019) would result in HIV elimination (less than one new infection per 1,000 person-years). However, whereas the simplest model predicted that UTT would eliminate HIV after seven years, the more complex, realistic models predicted elimination at much later time points. Importantly, the most comprehensive model predicted that, although elimination would be reached after about 17 years of UTT, the current strategy of ART initiation for HIV-positive individuals at a CD4 cell count at or below 350 cells/µl would also lead to HIV elimination, albeit ten years later than UTT.
What Do These Findings Mean?
These findings confirm previous predictions that UTT could eliminate HIV in South Africa, but the development of more realistic models than those used in the past suggests that HIV elimination would occur substantially later than originally predicted. Importantly, the most comprehensive model suggests that HIV could be eliminated in South Africa using the current strategy for ART treatment alone. As with all modeling studies, the accuracy of these findings depends on the assumptions built into the models and on the structure of the models. Thus, although these findings support the use of UTT as an intervention to eliminate HIV, more research with comprehensive models that incorporate factors such as data from ongoing trials of treatment as prevention is needed to determine the population-level impact and overall cost-effectiveness of UTT.
Additional Information
Please access these websites via the online version of this summary at
This study is further discussed in a PLOS Medicine Perspective by Ford and Hirnschall
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV and AIDS in South Africa, on HIV treatment as prevention and the possibility of HIV elimination (in English and Spanish)
The 2012 UNAIDS World AIDS Day Report provides up-to-date information about the AIDS epidemic and efforts to halt it
The World Health Organization provides information about universal access to AIDS treatment (in several languages); its 2010 ART guidelines can be downloaded
The PLOS Medicine Collection Investigating the Impact of Treatment on New HIV Infections provides more information about HIV treatment as prevention
Personal stories about living with HIV/AIDS are available through Avert, through NAM/aidsmap, and through the charity website Healthtalkonline
PMCID: PMC3805487  PMID: 24167449
21.  Effect of a web-based chronic disease management system on asthma control and health-related quality of life: study protocol for a randomized controlled trial 
Trials  2011;12:260.
Asthma is a prevalent and costly disease resulting in reduced quality of life for a large proportion of individuals. Effective patient self-management is critical for improving health outcomes. However, key aspects of self-management such as self-monitoring of behaviours and symptoms, coupled with regular feedback from the health care team, are rarely addressed or integrated into ongoing care. Health information technology (HIT) provides unique opportunities to facilitate this by providing a means for two way communication and exchange of information between the patient and care team, and access to their health information, presented in personalized ways that can alert them when there is a need for action. The objective of this study is to evaluate the acceptability and efficacy of using a web-based self-management system, My Asthma Portal (MAP), linked to a case-management system on asthma control, and asthma health-related quality of life.
The trial is a parallel multi-centered 2-arm pilot randomized controlled trial. Participants are randomly assigned to one of two conditions: a) MAP and usual care; or b) usual care alone. Individuals will be included if they are between 18 and 70, have a confirmed asthma diagnosis, and their asthma is classified as not well controlled by their physician. Asthma control will be evaluated by calculating the amount of fast acting beta agonists recorded as dispensed in the provincial drug database, and asthma quality of life using the Mini Asthma Related Quality of Life Questionnaire. Power calculations indicated a needed total sample size of 80 subjects. Data are collected at baseline, 3, 6, and 9 months post randomization. Recruitment started in March 2010 and the inclusion of patients in the trial in June 2010.
Self-management support from the care team is critical for improving chronic disease outcomes. Given the high volume of patients and time constraints during clinical visits, primary care physicians have limited time to teach and reinforce use of proven self-management strategies. HIT has the potential to provide clinicians and a large number of patients with tools to support health behaviour change.
Trial Registration
Current Controlled Trials ISRCTN34326236.
PMCID: PMC3268749  PMID: 22168530
22.  Comparison of the seasonal patterns of asthma identified in general practitioner episodes, hospital admissions, and deaths 
Thorax  2000;55(8):662-665.
BACKGROUND—Seasonal variations in asthma are widely recognised. This study was undertaken to investigate the relative differences in seasonal patterns by age as they impact on episodes of care in general practice, hospital admissions, and deaths.
METHODS—General practice episode data from the Weekly Returns Service of the Royal College of General Practitioners, hospital admissions for asthma in England, and deaths registered as due to asthma in England and Wales over the years 1990-7 were examined. Age specific weekly rates of new episodes of asthma presenting to general practitioners, numbers of hospital admissions and deaths were analysed by the multiplicative decomposition method to separate secular from seasonal trends. The seasonal indices thereby obtained were plotted as three week moving averages.
RESULTS—In children aged 0-4 and 5-14 years general practice episodes and admissions to hospital were strikingly congruent in timing and in magnitude, except in September when particularly high rates of admission (absolute and relative to general practice episodes) occurred. In the 15-44 age group there were marked mid summer peaks of general practice episodes and deaths but admissions to hospital were at about the annual average; in September/October there were peaks of episodes and admissions whereas deaths peaked in November. In the 45-64 age group a peak in general practice episodes of asthma was evident in mid summer when admissions were about average and deaths were at a minimum; all three measures tended to increase gradually with the approach of winter. Finally, in those age over 65 years, general practice episodes of asthma, admissions to hospital, and deaths followed similar `U' shaped patterns with substantial peaks in mid winter.
CONCLUSIONS—The seasonal pattern of asthma evolves with age. There are important differences in the seasonal pattern of general practice episodes, admissions to hospital, and deaths. Individual seasonal histories are important for the management of asthma. The combined analysis of these three data sets provides a new perspective on the epidemiology of asthma.

PMCID: PMC1745832  PMID: 10899242
23.  Development and pilot testing of a mobile health solution for asthma self-management: Asthma action plan smartphone application pilot study 
Collaborative self-management is a core recommendation of national asthma guidelines; the written action plan is the knowledge tool that supports this objective. Mobile health technologies have the potential to enhance the effectiveness of the action plan as a knowledge translation tool.
To design, develop and pilot a mobile health system to support asthma self-management.
The present study was a prospective, single-centre, nonrandomized, pilot preintervention-postintervention analysis. System design and development were guided by an expert steering committee. The network included an agnostic web browser-based asthma action plan smart-phone application (SPA). Subjects securely transmitted symptoms and peak flow data daily, and received automated control assessment, treatment advice and environmental alerts.
Twenty-two adult subjects (mean age 47 years, 82% women) completed the study. Biophysical data were received on 84% of subject days (subject day = 1 subject × 1 day). Subjects viewed their action plan current zone of control on 54% and current air quality on 61% of subject days, 86% followed self-management advice and 50% acted to reduce exposure risks. A large majority affirmed ease of use, clarity and timeliness, and 95% desired SPA use after the study. At baseline, 91% had at least one symptom criterion for uncontrolled asthma and 64% had ≥2, compared with 45% (P=0.006) and 27% (P=0.022) at study close. Mean Asthma Quality of Life Questionnaire score improved from 4.3 to 4.8 (P=0.047).
A dynamic, real-time, interactive, mobile health system with an integrated asthma action plan SPA can support knowledge translation at the patient and provider levels.
PMCID: PMC3956342  PMID: 23936890
Asthma; Cellular phone; Guideline adherence; Implementation; Knowledge translation; Patient education as topic; Primary care
24.  The Breathe Easier through Weight Loss Lifestyle (BE WELL) Intervention: A randomized controlled trial 
Obesity and asthma have reached epidemic proportions in the US. Their concurrent rise over the last 30 years suggests that they may be connected. Numerous observational studies support a temporally-correct, dose-response relationship between body mass index (BMI) and incident asthma. Weight loss, either induced by surgery or caloric restriction, has been reported to improve asthma symptoms and lung function. Due to methodological shortcomings of previous studies, however, well-controlled trials are needed to investigate the efficacy of weight loss strategies to improve asthma control in obese individuals.
BE WELL is a 2-arm parallel randomized clinical trial (RCT) of the efficacy of an evidence-based, comprehensive, behavioral weight loss intervention, focusing on diet, physical activity, and behavioral therapy, as adjunct therapy to usual care in the management of asthma in obese adults. Trial participants (n = 324) are patients aged 18 to 70 years who have suboptimally controlled, persistent asthma, BMI between 30.0 and 44.9 kg/m2, and who do not have serious comorbidities (e.g., diabetes, heart disease, stroke). The 12-month weight loss intervention to be studied is based on the principles of the highly successful Diabetes Prevention Program lifestyle intervention. Intervention participants will attend 13 weekly group sessions over a four-month period, followed by two monthly individual sessions, and will then receive individualized counseling primarily by phone, at least bi-monthly, for the remainder of the intervention. Follow-up assessment will occur at six and 12 months. The primary outcome variable is the overall score on the Juniper Asthma Control Questionnaire measured at 12 months. Secondary outcomes include lung function, asthma-specific and general quality of life, asthma medication use, asthma-related and total health care utilization. Potential mediators (e.g., weight loss and change in physical activity level and nutrient intake) and moderators (e.g., socio-demographic characteristics and comorbidities) of the intervention effects also will be examined.
This RCT holds considerable potential for illuminating the nature of the obesity-asthma relationship and advancing current guidelines for treating obese adults with asthma, which may lead to reduced morbidity and mortality related to the comorbidity of the two disorders.
Trial registration
PMCID: PMC2860346  PMID: 20334686
25.  Outdoor air pollution and emergency department visits for asthma among children and adults: A case-crossover study in northern Alberta, Canada 
Environmental Health  2007;6:40.
Recent studies have observed positive associations between outdoor air pollution and emergency department (ED) visits for asthma. However, few have examined the possible confounding influence of aeroallergens, or reported findings among very young children.
A time stratified case-crossover design was used to examine 57,912 ED asthma visits among individuals two years of age and older in the census metropolitan area of Edmonton, Canada between April 1, 1992 and March 31, 2002. Daily air pollution levels for the entire region were estimated from three fixed-site monitoring stations. Similarly, daily levels of aeroallergens were estimated using rotational impaction sampling methods for the period between 1996 and 2002. Odds ratios and their corresponding 95% confidence intervals were estimated using conditional logistic regression with adjustment for temperature, relative humidity and seasonal epidemics of viral related respiratory disease.
Positive associations for asthma visits with outdoor air pollution levels were observed between April and September, but were absent during the remainder of the year. Effects were strongest among young children. Namely, an increase in the interquartile range of the 5-day average for NO2 and CO levels between April and September was associated with a 50% and 48% increase, respectively, in the number of ED visits among children 2 – 4 years of age (p < 0.05). Strong associations were also observed with these pollutants among those 75 years of age and older. Ozone and particulate matter were also associated with asthma visits. Air pollution risk estimates were largely unchanged after adjustment for aeroallergen levels.
Our findings, taken together, suggest that exposure to ambient levels of air pollution is an important determinant of ED visits for asthma, particularly among young children and the elderly.
PMCID: PMC2254596  PMID: 18157917

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