Articles tagged as "Singapore"

How do we know which activities make a difference to HIV prevention?

Editor’s notes: In order to be fairly certain that an intervention is responsible for changes in HIV or HIV-related behaviours, the gold standard is randomization. This allows for fair comparisons between groups, since factors that might alter the outcomes will be more or less equally balanced between the study groups.  This is true whether such confounding factors are expected, but also importantly, even those factors that are unknown, unexpected and unmeasured will also be balanced between the arms. 

A second key determinant of high quality research is to use an approach that maximizes full engagement and follow-up of participants in the study.  One such approach that is widely recognized is to use Good Participatory Practice.  

Rhodes and colleagues study condom promotion and HIV testing among the Hispanic/Latino community of gay men and other men who have sex with men in North Carolina, USA.  Although gay men and other men who have sex with men represent approximately 4% of the adult male population in the United States of America, they account for more than 80% of new HIV infections among men.  Around one quarter of gay men and other men who have sex with men are Hispanic or Latino.  The authors therefore wanted to use research to make a difference to the HIV burden of the Hispanic/Latino gay men and other men who have sex with men community in North Carolina, USA.  They found that despite the impact of HIV on Hispanic/ Latino gay men and other men who have sex with men, they were only able to identify one evidence-based behavioural HIV prevention programme focussed on this population.

The authors used an extensive community based participatory research partnership, whose members represented the Hispanic/ Latino gay men and other men who have sex with men community, AIDS service organizations, Hispanic/Latino-serving community organizations, and universities to develop, implement, and evaluate a Spanish-language, small group intervention designed to increase condom use and HIV testing among Hispanic/Latino gay men and other men who have sex with men (HOLA en Grupos).

304 participants were randomly allocated to the HOLA en Grupos intervention, or to a general health education comparison intervention having the same number of sessions (4) and duration (16 hours in total) that focussed on prostate, lung, and colorectal cancers; diabetes; high cholesterol; cardiovascular disease; and alcohol misuse. These topics for the control group were identified on the basis of identified needs and priorities of Hispanic/Latino gay men and other men who have sex with men.

HOLA en Grupos is grounded on social cognitive theory, empowerment education, and traditional Hispanic/Latino cultural values and includes four interactive modules of four hours each delivered in groups.  Participants in both intervention and control arms received reimbursement for their time, certificates of completion and meals and a celebration at the completion of the course.  In other words this was an intensive intervention that might be hard to replicate in most settings, but it follows very high standards both for developing and conducting the research and also for determining the impact of the intervention.

The intervention was associated with a large effect on both condom usage (four-fold higher in the intervention arm than the control) and HIV test uptake (an astonishing 14-fold higher, reflecting the relatively low testing rate in the control group).

A major limitation in many HIV prevention studies, including this one, is that the outcome is based on reported behaviour.  The challenge is that the real outcome of interest, which is new HIV infections, is relatively rare in almost all communities so that studies have to be huge and expensive, and the large majority of participants in both intervention and control arms do not in fact acquire HIV.  This is in contrast to most studies of treatment, where there are clearly defined biological, standardized measures which many or all participants are likely to reach.  Nonetheless, there are many examples of studies that find changes in reported behaviour that are not associated with biological markers of such change (such as incidence of HIV or other sexually transmitted infections, or pregnancy). 

There are also many observational or ecological studies that report changes in new HIV infections but that cannot truly say why the number of infections fell and whether the interventions used in the study were responsible for the changes.  For example Nwokolo and colleagues report in a short research letter on the dramatic decline in new HIV diagnoses in the large London clinic where they work.  New infections in that clinic, and in fact in other large clinics in London, have dropped by a remarkable 40% from 2015 to 2016, as originally reported in the popular science press before any scientific publication or presentation. The authors of the research letter are suitably cautious about how to account for the impressive decline.  Various systems have been improved over the past few years in this clinic to make it easier to have an HIV test and start treatment immediately.  However, most of the clinic team (and many other commentators) assume that it is also due to the rapid rise in the use of PrEP.  Although it is still not available through the UK National Health Service, the clinic has been at the forefront of encouraging gay men and other men who have sex with men who might benefit from PrEP to purchase it from on-line pharmacies.  The clinic then provides the appropriate monitoring and follow up to ensure that their clients get the best possible PrEP service given the current constraints.  Whatever the cause, we should be celebrating the rapid fall in new HIV infections across London, which is home to a substantial proportion of the new HIV infections in the UK.

The challenges of demonstrating evidence of effectiveness for HIV prevention is also felt among black women in the USA.  Although they have the highest burden of HIV among women in the USA, the incidence rates are such that a traditional randomized trial design would need to be huge, and consequently hugely expensive.  Adimora and colleagues consider whether an alternative trial design might be to use data from high HIV incidence settings and then to develop proxies of protection, such as the concentration of a PrEP medicine to infer whether black women are protected.  An alternative that has been proposed for men who have sex with men would be to look for other markers of high risk, such as sexually transmitted infections, reported partners, age, and substance use and estimate the likely risk of HIV acquisition in the absence of PrEP from these parameters.  Then the observed incidence could be compared to this modelled counterfactual, much as was done in the open label extension of the Partners PrEP study in Kenyan and Ugandan sero-different couples.  However, translating risk factors for infection across populations, and even continents when there is such heterogeneity in risk of infection is not at all straightforward.  So there is still plenty to think about and no clear answers yet!

A useful addition to the tool box for designing studies and assessing the effectiveness of interventions, would be better tools for measuring recent infection.  There are several assays all with differing characteristics but increasingly these differences and how they interact with different clades of HIV are becoming clear.  Key determinants for each assay are the mean duration of recent infection (MDRI) estimate (which does seem to vary by clade) and the false recency rate (FRR) which needs to be less than 2% to be considered useful.  Hargrove and colleagues used three different assays to test samples from 101 women who seroconverted during the ZVITAMBO trial.  The MDRI measured using standard cut-off points, were considerably shorter than those published for the general population.  The authors point out that changes in antibody properties among women who have recently given birth or other unspecified physiological states, mean that incidence assays may give different results from those published and expected.  Yet more caution when comparing incidence estimates between studies.  As an endpoint in a comparison between two groups in the same population, the assays are still attractive. Although, given typical MDRIs of around six to nine months, these assays will still need to be embedded in very large samples to give reliable estimates of incidence and statistically significant differences between groups.

This month saw the production of a useful supplement on many aspects of how data from different sources, including incidence assays are used to inform the sophisticated models on which so much HIV planning, programming and financing is based.  An example is Mahiane and colleagues’ paper on the development of a new tool to fit existing programme data into the spectrum suite of models in order to estimate incidence.

Finally in this section, for those who are keen on laboratory studies, Richardson-Harman and colleagues describe the current state of ex-vivo challenge models for assessing potential candidates as microbicides.  In these models, biopsies of rectal, cervical or vaginal tissue, taken during other procedures, or from volunteers, are kept alive in the laboratory.  The tissues can then be challenged with HIV in the presence or absence of potential microbicide products.  The current model works best for rectal tissues, in which infection occurs promptly and consistently, so that the effect of a microbicide can clearly be seen by a reduction in the production of HIV p24 antigen.  However, for cervical and vaginal tissues, the infection (in the absence of any microbicide) was less consistent, slower and lasted longer making it less easy to determine statistical differences between those tissues with microbicide and those without.  Further work of this sort may help to streamline the choice of microbicide or PrEP products that can most sensibly be taken out of the laboratory and into the (almost) real world of clinical trials.

Small-group randomized controlled trial to increase condom use and HIV testing among Hispanic/Latino gay, bisexual, and other men who have sex with men.

Rhodes SD, Alonzo J, Mann L, Song EY, Tanner AE, Arellano JE, Rodriguez-Celedon R, Garcia M, Freeman A, Reboussin BA, Painter TM. Am J Public Health. 2017 Jun;107(6):969-976. doi: 10.2105/AJPH.2017.303814. Epub 2017 Apr 20.

Objectives: To evaluate the HOLA en Grupos intervention, a Spanish-language small-group behavioral HIV prevention intervention designed to increase condom use and HIV testing among Hispanic/Latino gay, bisexual, and other men who have sex with men.

Methods: In 2012 to 2015, we recruited and randomized 304 Hispanic/Latino men who have sex with men, aged 18 to 55 years in North Carolina, to the 4-session HOLA en Grupos intervention or an attention-equivalent general health education comparison intervention. Participants completed structured assessments at baseline and 6-month follow-up. Follow-up retention was 100%.

Results: At follow-up, relative to comparison participants, HOLA en Grupos participants reported increased consistent condom use during the past 3 months (adjusted odds ratio [AOR] = 4.1; 95% confidence interval [CI] = 2.2, 7.9; P < .001) and HIV testing during the past 6 months (AOR = 13.8; 95% CI = 7.6, 25.3; P < .001). HOLA en Grupos participants also reported increased knowledge of HIV (P < .001) and sexually transmitted infections (P < .001); condom use skills (P < .001), self-efficacy (P < .001), expectancies (P < .001), and intentions (P < .001); sexual communication skills (P < .01); and decreased fatalism (P < .001).

Conclusions: The HOLA en Grupos intervention is efficacious for reducing HIV risk behaviors among Hispanic/Latino men who have sex with men.

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Not just PrEP: other reasons for London's HIV decline.

Nwokolo N, Whitlock G, McOwan A. Lancet HIV. 2017 Apr;4(4):e153. doi: 10.1016/S2352-3018(17)30044-9.

The reduction in HIV diagnoses in London in 2016 is attributed to pre-exposure prophylaxis (PrEP). We believe that the causes of the 42% decline seen at our clinic are likely to be multifactorial. 56 Dean Street diagnoses one in four of London's HIV cases, 50% of whom have incident infection (ie, within 4 months of infection). Because of this, and following the results of the START study, we actively recommend treatment at, or close to, diagnosis, reducing the risk of transmission in people who would otherwise be highly infectious.

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US black women and HIV prevention: time for new approaches to clinical trials.

Adimora AA, Cole SR, Eron JJ Clin Infect Dis. 2017 Apr 5. doi: 10.1093/cid/cix313. [Epub ahead of print]. 

Black women bear the highest burden of HIV infection among US women. Tenofovir/ emtricitabine HIV prevention trials among women in Africa have yielded varying results. Ideally, a randomized controlled trial (RCT) among US women would provide data for guidelines for US women's HIV pre-exposure prophylaxis use. However, even among US black women at high risk for HIV infection, sample size requirements for an RCT with HIV incidence as its outcome are prohibitively high. We propose to circumvent this large sample size requirement by evaluating relationships between HIV incidence and drug concentrations measured among participants in traditional phase 3 trials in high incidence settings - and then applying these observations to drug concentrations measured among at risk individuals in lower incidence settings, such as US black women. This strategy could strengthen the evidence base to enable black women to fully benefit from prevention research advances and decrease racial disparities in HIV rates.

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Heightened HIV antibody responses in postpartum women as exemplified by recent infection assays: implications for incidence estimates.

Hargrove JW, van Schalkwyk C, Humphrey JH, Mutasa K, Ntozini R, Owen SM, Masciotra S, Parekh BS, Duong YT, Dobbs T, Kilmarx PH, Gonese E. AIDS Res Hum Retroviruses. 2017 May 24. doi: 10.1089/AID.2016.0319. [Epub ahead of print].

Laboratory assays that identify recent HIV infections are important for assessing impacts of interventions aimed at reducing HIV incidence. Kinetics of HIV humoral responses can vary with inherent assay properties, and between HIV subtypes, populations, and physiological states. They are important in determining mean duration of recent infection (MDRI) for antibody-based assays for detecting recent HIV infections. We determined MDRIs for multi-subtype peptide representing subtypes B, E and D (BED)-capture enzyme immunoassay, limiting antigen (LAg), and Bio-Rad Avidity Incidence (BRAI) assays for 101 seroconverting postpartum women, recruited in Harare from 1997 to 2000 during the Zimbabwe Vitamin A for Mothers and Babies trial, comparing them against published MDRIs estimated from seroconverting cases in the general population. We also compared MDRIs for women who seroconverted either during the first 9 months, or at later stages, postpartum. At cutoffs (C) of 0.8 for BED, 1.5 for LAg, and 40% for BRAI, estimated MDRIs for postpartum mothers were 192, 104, and 144 days, 33%, 32%, and 52% lower than published estimates of 287, 152 and 298 days, respectively, for clade C samples from general populations. Point estimates of MDRI values were 7%-19% shorter for women who seroconverted in the first 9 months postpartum than for those seroconverting later. MDRI values for three HIV incidence biomarkers are longer in the general population than among postpartum women, particularly those who recently gave birth, consistent with heightened immunological activation soon after birth. Our results provide a caution that MDRI may vary significantly between subjects in different physiological states.

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Improvements in Spectrum's fit to program data tool.

Mahiane SG, Marsh K, Grantham K, Crichlow S, Caceres K, Stover J.  AIDS. 2017 Apr;31 Suppl 1:S23-S30. doi: 10.1097/QAD.0000000000001359.

Objective: The Joint United Nations Program on HIV/AIDS-supported Spectrum software package (Glastonbury, Connecticut, USA) is used by most countries worldwide to monitor the HIV epidemic. In Spectrum, HIV incidence trends among adults (aged 15-49 years) are derived by either fitting to seroprevalence surveillance and survey data or generating curves consistent with program and vital registration data, such as historical trends in the number of newly diagnosed infections or people living with HIV and AIDS related deaths. This article describes development and application of the fit to program data (FPD) tool in Joint United Nations Program on HIV/AIDS' 2016 estimates round.

Methods: In the FPD tool, HIV incidence trends are described as a simple or double logistic function. Function parameters are estimated from historical program data on newly reported HIV cases, people living with HIV or AIDS-related deaths. Inputs can be adjusted for proportions undiagnosed or misclassified deaths. Maximum likelihood estimation or minimum chi-squared distance methods are used to identify the best fitting curve. Asymptotic properties of the estimators from these fits are used to estimate uncertainty.

Results: The FPD tool was used to fit incidence for 62 countries in 2016. Maximum likelihood and minimum chi-squared distance methods gave similar results. A double logistic curve adequately described observed trends in all but four countries where a simple logistic curve performed better.

Conclusion: Robust HIV-related program and vital registration data are routinely available in many middle-income and high-income countries, whereas HIV seroprevalence surveillance and survey data may be scarce. In these countries, the FPD tool offers a simpler, improved approach to estimating HIV incidence trends.

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Analytical advances in the ex vivo challenge efficacy assay.

Richardson-Harman N, Parody R, Anton P, McGowan I, Doncel G, Thurman AR, Herrera C, Kordy K, Fox J, Tanner K, Swartz G, Dezzutti CS. AIDS Res Hum Retroviruses. 2017 Apr;33(4):395-403. doi: 10.1089/AID.2016.0073. Epub 2016 Dec 16.

The ex vivo challenge assay is being increasingly used as an efficacy endpoint during early human clinical trials of HIV prevention treatments. There is no standard methodology for the ex vivo challenge assay, although the use of different data collection methods and analytical parameters may impact results and reduce the comparability of findings between trials. In this analysis, we describe the impact of data imputation methods, kit type, testing schedule and tissue type on variability, statistical power, and ex vivo HIV growth kinetics. Data were p24 antigen (pg/ml) measurements collected from clinical trials of candidate microbicides where rectal (n = 502), cervical (n = 88), and vaginal (n = 110) tissues were challenged with HIV-1BaL ex vivo. Imputation of missing data using a nonlinear mixed effect model was found to provide an improved fit compared to imputation using half the limit of detection. The rectal virus growth period was found to be earlier and of a relatively shorter duration than the growth period for cervical and vaginal tissue types. On average, only four rectal tissue challenge assays in each treatment and control group would be needed to find a one log difference in p24 to be significant (alpha = 0.05), but a larger sample size was predicted to be needed for either cervical (n = 21) or vaginal (n = 10) tissue comparisons. Overall, the results indicated that improvements could be made in the design and analysis of the ex vivo challenge assay to provide a more standardized and powerful assay to compare efficacy of microbicide products.

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Tenofovir resistance – need for caution but not panic

Global epidemiology of drug resistance after failure of WHO recommended first-line regimens for adult HIV-1 infection: a multicentre retrospective cohort study.

TenoRes Study Group. Lancet Infect Dis. 2016 Jan 28. pii: S1473-3099(15)00536-8. doi: 10.1016/S1473-3099(15)00536-8. [Epub ahead of print]

Background: Antiretroviral therapy (ART) is crucial for controlling HIV-1 infection through wide-scale treatment as prevention and pre-exposure prophylaxis (PrEP). Potent tenofovir disoproxil fumarate-containing regimens are increasingly used to treat and prevent HIV, although few data exist for frequency and risk factors of acquired drug resistance in regions hardest hit by the HIV pandemic. We aimed to do a global assessment of drug resistance after virological failure with first-line tenofovir-containing ART.

Methods: The TenoRes collaboration comprises adult HIV treatment cohorts and clinical trials of HIV drug resistance testing in Europe, Latin and North America, sub-Saharan Africa, and Asia. We extracted and harmonised data for patients undergoing genotypic resistance testing after virological failure with a first-line regimen containing tenofovir plus a cytosine analogue (lamivudine or emtricitabine) plus a non-nucleotide reverse-transcriptase inhibitor (NNRTI; efavirenz or nevirapine). We used an individual participant-level meta-analysis and multiple logistic regression to identify covariates associated with drug resistance. Our primary outcome was tenofovir resistance, defined as presence of K65R/N or K70E/G/Q mutations in the reverse transcriptase (RT) gene.

Findings: We included 1926 patients from 36 countries with treatment failure between 1998 and 2015. Prevalence of tenofovir resistance was highest in sub-Saharan Africa (370/654 [57%]). Pre-ART CD4 cell count was the covariate most strongly associated with the development of tenofovir resistance (odds ratio [OR] 1.50, 95% CI 1.27-1.77 for CD4 cell count <100 cells per µL). Use of lamivudine versus emtricitabine increased the risk of tenofovir resistance across regions (OR 1.48, 95% CI 1.20-1.82). Of 700 individuals with tenofovir resistance, 578 (83%) had cytosine analogue resistance (M184V/I mutation), 543 (78%) had major NNRTI resistance, and 457 (65%) had both. The mean plasma viral load at virological failure was similar in individuals with and without tenofovir resistance (145 700 copies per mL [SE 12 480] versus 133 900 copies per mL [SE 16 650; p=0.626]).

Interpretation: We recorded drug resistance in a high proportion of patients after virological failure on a tenofovir-containing first-line regimen across low-income and middle-income regions. Effective surveillance for transmission of drug resistance is crucial.

Abstract  Full-text [free] access 

Editor’s notes: Global surveillance for tenofovir (TDF) resistance is important at a time of expanding use of TDF-containing regimens for treatment and prevention. This collaborative analysis used data collated from several small studies in different settings. Overall, around one in three people who had failed on TDF-containing treatment had evidence of TDF resistance, although this frequency varied between 20% in Europe to almost 60% in Africa. Mutations associated with NNRTIs and lamivudine/emtricitabine resistance were more common overall and were present in most people with TDF resistance.

The regional variation probably reflects differences in clinical practice and study inclusion criteria. All European studies involved cohorts with frequent viral load monitoring, whereas half of the African cohorts had no routine viral load monitoring. All European studies included people with virologic failure but with low-level viraemia (viral load <1000 copies/ml) whereas almost all African studies included only people with viral load >1000 copies/ml.

While these data provide useful estimates of the frequency of drug resistance mutations in people with virologic failure on first-line ART, there should be caution about extrapolating beyond this. Reports from cohort studies with an accurate denominator of all people starting TDF-containing first-line ART would be useful to give more reliable estimates of overall incidence of acquired TDF resistance. Moreover, there remains a need for representative population-based surveillance for acquired and transmitted drug resistance. So far, global surveillance has detected limited evidence of transmitted TDF-associated mutations, but this needs to be monitored closely, especially in high incidence settings.

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AIDS and bacterial disease remain leading causes of hospital admission

Causes of hospital admission among people living with HIV worldwide: a systematic review and meta-analysis.

Ford N, Shubber Z, Meintjes G, Grinsztejn B, Eholie S, Mills EJ, Davies MA, Vitoria M, Penazzato M, Nsanzimana S, Frigati L, O'Brien D, Ellman T, Ajose O, Calmy A, Doherty M. Lancet HIV. 2015 Oct;2(10):e438-44. doi: 10.1016/S2352-3018(15)00137-X. Epub 2015 Aug 11.

Background: Morbidity associated with HIV infection is poorly characterised, so we aimed to investigate the contribution of different comorbidities to hospital admission and in-hospital mortality in adults and children living with HIV worldwide.

Methods: Using a broad search strategy combining terms for hospital admission and HIV infection, we searched MEDLINE via PubMed, Embase, Web of Science, LILACS, AIM, IMEMR and WPIMR from inception to Jan 31, 2015, to identify studies reporting cause of hospital admission in people living with HIV. We focused on data reported after 2007, the period in which access to antiretroviral therapy started to become widespread. We estimated pooled proportions of hospital admissions and deaths per disease category by use of random-effects models. We stratified data by geographical region and age.

Findings: We obtained data from 106 cohorts, with reported causes of hospital admission for  313 006 adults and 6182 children living with HIV. For adults, AIDS-related illnesses (25 119 patients, 46%, 95% CI 40-53) and bacterial infections (14 034 patients, 31%, 20-42) were the leading causes of hospital admission. These two categories were the most common causes of hospital admission for adults in all geographical regions and the most common causes of mortality. Common region-specific causes of hospital admission included malnutrition and wasting, parasitic infections, and haematological disorders in the Africa region; respiratory disease, psychiatric disorders, renal disorders, cardiovascular disorders, and liver disease in Europe; haematological disorders in North America; and respiratory, neurological, digestive and liver-related conditions, viral infections, and drug toxicity in South and Central America. For children, AIDS-related illnesses (783 patients, 27%, 95% CI 19-34) and bacterial infections (1190 patients, 41%, 26-56) were the leading causes of hospital admission, followed by malnutrition and wasting, haematological disorders, and, in the African region, malaria. Mortality in individuals admitted to hospital was 20% (95% CI 18-23, 12 902 deaths) for adults and 14% (10-19, 643 deaths) for children.

Interpretation: This review shows the importance of prompt HIV diagnosis and treatment, and the need to reinforce existing recommendations to provide chemoprophylaxis and vaccination against major preventable infectious diseases to people living with HIV to reduce serious AIDS and non-AIDS morbidity.

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Editor’s notes: Despite the widening availability of antiretroviral therapy (ART), HIV-associated disease remains an important cause of illness and death. In this systematic review the authors summarise published data concerning causes of hospital admission among HIV-positive people since 2007. This date was selected on the basis that access to ART was limited prior to 2007.

Overall the most common causes of admission among adults, across all geographical regions, were AIDS-associated illness and bacterial infections. Tuberculosis was the most common cause among adults, accounting for 18% of all admissions, followed by bacterial pneumonia (15%). Among children, similarly AIDS-associated illnesses (particularly tuberculosis and Pneumocystis pneumonia) and bacterial infections were the most common causes of admission. Among the 20% of adults who died during their admission, the most common causes of death were tuberculosis, bacterial infections, cerebral toxoplasmosis and cryptococcal meningitis. Among children the most common causes of death were tuberculosis, bacterial infections and Pneumocystis pneumonia. Tuberculosis is likely to have been underestimated in these studies. Autopsy studies consistently illustrate that around half of HIV-positive people who have tuberculosis identified at autopsy had not been diagnosed prior to death.

The review highlights that the majority of severe HIV-associated disease remains attributable to advanced immunosuppression. This is reflected by a median CD4 count at admission among adults of 168 cells per µl. Some 30% of people first tested HIV positive at the time of the admission. The review underlines the need to promote HIV testing so that HIV-positive people can access ART, and prevent the complications of advanced HIV disease. It also underscores the need for better coverage of screening for tuberculosis and preventive therapy for people without active disease.  

Avoid TB deaths
Comorbidity, Epidemiology
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Can a simple risk score predict chronic kidney disease among people living with HIV?

Development and validation of a risk score for chronic kidney disease in HIV infection using prospective cohort data from the D:A:D study.

Mocroft A, Lundgren JD, Ross M, Law M, Reiss P, Kirk O, Smith C, Wentworth D, Neuhaus J, Fux CA, Moranne O, Morlat P, Johnson MA, Ryom L, D:A:D study group, the Royal Free Hospital Clinic Cohort, and the INSIGHT, SMART, and ESPRIT study groups. PLoS Med. 2015 Mar 31;12(3):e1001809. doi: 10.1371/journal.pmed.1001809. eCollection 2015.

Background: Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice.

Methods and findings: A total of 17 954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with ≥3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR >60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR ≤60 ml/min/1.73 m2. Poisson regression was used to develop a risk score, externally validated on two independent cohorts. In the D:A:D study, 641 individuals developed CKD during 103 185 person-years of follow-up (PYFU; incidence 6.2/1000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1:393 chance of developing CKD in the next 5 y in the low risk group (risk score <0, 33 events), rising to 1:47 and 1:6 in the medium (risk score 0-4, 103 events) and high risk groups (risk score ≥5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1702 (95% CI 1166-3367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2548 individuals, of whom 94 individuals developed CKD (3.7%) during 18 376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria.

Conclusions: Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.

Abstract  Full-text [free] access

Editor’s notes: The nephrotoxicity of antiretroviral drugs, particularly tenofovir, is of concern, particularly where there is limited access to laboratory monitoring of kidney function. The development of kidney impairment among people with HIV is associated with poor outcomes, and in low resource settings where dialysis is not available this can be catastrophic.

This study, like previous work, attempts to address this problem by developing a risk score for the development of chronic kidney disease (CKD). The strength of this study is the availability of data for over 17 000 men and women living with HIV enrolled in cohort studies for many years, and in over 40 countries globally. The resulting risk score uses nine simple clinical variables which predict CKD both overall, and after starting potentially nephrotoxic antiretrovirals. A short risk score, not including cardiovascular risk factors, which may be more suitable for low resource settings, shows almost as good a prediction of CKD.

So will this risk score become widely used in clinical decision making? For high income countries this tool may be useful to identify people where strategies to prevent cardiovascular and renal disease are best focussed. It may also be useful to identify people at high risk of developing CKD for whom use of tenofovir may be unacceptable, especially when monitoring of kidney function is limited. However, few of the enrolled people were from low and middle income countries, and there was limited information on the race of participants. Therefore, the risk score may need to be validated in low resource settings before it can be widely used. Whether the use of the tool would help to improve clinical outcomes where kidney function is frequently monitored is unclear.

Meanwhile, a new drug formulation, tenofovir alafenamide (TAF), is currently in clinical trials. This appears to be associated with less renal toxicity, and to be safe and well tolerated among adults with decreased kidney function. If future trial results support this evidence, and tenofovir alafenamide becomes widely available, concern about drug nephrotoxicity may become a less pressing clinical issue.

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Improved delivery of isoniazid preventive therapy with integrated HIV and TB services

Interventions to improve delivery of isoniazid preventive therapy: an overview of systematic reviews

Adams LV, Talbot EA, Odato K, Blunt H, Steingart KR. BMC Infect Dis. 2014 May 21;14(1):281. doi: 10.1186/1471-2334-14-281.

Background: Uptake of isoniazid preventive therapy (IPT) to prevent tuberculosis has been poor, particularly in the highest risk populations. Interventions to improve IPT delivery could promote implementation. The large number of existing systematic reviews on treatment adherence has made drawing conclusions a challenge. To provide decision makers with the evidence they need, we performed an overview of systematic reviews to compare different organizational interventions to improve IPT delivery as measured by treatment completion among those at highest risk for the development of TB disease, namely child contacts or HIV-infected individuals.

Methods: We searched the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects (DARE), and MEDLINE up to August 15, 2012. Two authors used a standardized data extraction form and the AMSTAR instrument to independently assess each review.

Results: Six reviews met inclusion criteria. Interventions included changes in the setting/site of IPT delivery, use of quality monitoring mechanisms (e.g., directly observed therapy), IPT delivery integration into other healthcare services, and use of lay health workers. Most reviews reported a combination of outcomes related to IPT adherence and treatment completion rate but without a baseline or comparison rate. Generally, we found limited evidence to demonstrate that the studied interventions improved treatment completion.

Conclusions: While most of the interventions were not shown to improve IPT completion, integration of tuberculosis and HIV services yielded high treatment completion rates in some settings. The lack of data from high burden TB settings limits applicability. Further research to assess different IPT delivery interventions, including those that address barriers to care in at-risk populations, is urgently needed to identify the most effective practices for IPT delivery and TB control in high TB burden settings.

Abstract  Full-text [free] access

Editor’s notes: Isoniazid preventive therapy (IPT) is a key component of the “3 Is” strategy to reduce tuberculosis among people living with HIV. Despite evidence of efficacy, initiation of IPT among eligible people in HIV care programmes has been disappointing. When IPT has been delivered as a stand-alone activity, treatment completion has often been poor. This overview of systematic reviews brings together evidence concerning organisational programmes to improve IPT delivery, using treatment completion as the main outcome. Three of the six included reviews, specifically included HIV-positive people.

When IPT delivery was integrated into other services, such as HIV care, good IPT completion rates were reported. A common weakness in the studies reviewed, was the lack of a suitable comparison group. This made it difficult to be sure that the good outcomes were due to the service integration. HIV This Month reported in June 2014 a trial from South Africa, showing that IPT reduces TB incidence among people taking antiretroviral therapy. Viewed together, these studies provide additional evidence supporting IPT delivery as part of the package of care for people in HIV care. More research is needed to guide implementers on how to deliver TB preventive therapy most effectively for people living with HIV.

Avoid TB deaths
Africa, Asia, Europe, Northern America
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Efavirenz dose reduction could help scale up antiretroviral therapy access

Efficacy of 400 mg efavirenz versus standard 600 mg dose in HIV-infected, antiretroviral-naive adults (ENCORE1): a randomised, double-blind, placebo-controlled, non-inferiority trial.

ENCORE1 Study Group. Lancet. 2014 Feb 7. pii: S0140-6736(13)62187-X. doi: 10.1016/S0140-6736(13)62187-X. [Epub ahead of print]

Background: The optimum dose of key antiretroviral drugs is often overlooked during product development. The ENCORE1 study compared the efficacy and safety of reduced dose efavirenz with standard dose efavirenz in combination with tenofovir and emtricitabine as first-line treatment for HIV infection. An effective and safe reduced dose could yield meaningful cost savings.

Methods: ENCORE1 is a continuing non-inferiority trial in HIV-1-infected antiretroviral-naive adults in 38 clinical sites in 13 countries. Participants (plasma HIV-RNA >1000 log10 copies per mL, CD4 T-cell count 50-500 cells per µL) were randomly assigned by a computer-generated sequence with a blocking factor of four (stratified by clinical site and by screening viral load) to receive tenofovir plus emtricitabine with either a reduced daily dose (400 mg) or a standard dose (600 mg) of efavirenz. Participants, physicians, and all other trial staff were masked to treatment group. The primary endpoint was the difference in proportions of participants with plasma HIV-RNA of less than 200 copies per mL at 48 weeks. Treatment groups were regarded as non-inferior if the lower limit of the 95% CI for the difference in viral load was less than -10% by modified intention-to-treat analysis. Adverse events were summarised by treatment.

Findings: The modified intention-to-treat analysis consisted of 630 patients (efavirenz 400=321; efavirenz 600=309). 32% were women; 37% were African, 33% were Asian, and 30% were white. The mean baseline CD4 cell count was 273 cells per µL (SD 99) and median plasma HIV-RNA was 4.75 log10 copies per mL (IQR 0.88). The proportion of participants with a viral load below 200 copies per mL at week 48 was 94.1% for efavirenz 400 mg and 92.2% for 600 mg (difference 1.85%, 95% CI -2.1 to 5.79). CD4 T-cell counts at week 48 were significantly higher for the 400 mg group than for the 600 mg group (mean difference 25 cells per µL, 95% CI 6-44; p=0.01). We recorded no difference in grade or number of patients reporting adverse events (efavirenz 400=89.1%, efavirenz 600=88.4%; difference 0.75%, 95% CI -4.19 to 5.69; p=0.77). Study drug-related adverse events were significantly more frequent in the 600 mg group than in the 400 mg group (146% [47] vs 118 [37]), difference -10.5%, 95% CI -18.2 to -2.8; p=0.01) and significantly fewer patients with these events stopped treatment (400 mg=6 [2%], 600 mg=18 [6%], difference -3.96%, 95% CI -6.96 to -0.95; p=0.01).

Interpretation: Our findings suggest that a reduced dose of 400 mg efavirenz is non-inferior to the standard dose of 600 mg, when combined with tenofovir and emtricitabine during 48 weeks in ART-naive adults with HIV-1 infection. Adverse events related to the study drug were more frequent with 600 mg efavirenz than with 400 mg. Lower dose efavirenz should be recommended as part of routine care.

Abstract access

Editor’s notes: Nearly 10 million people in low- and middle-income countries were receiving antiretroviral therapy (ART) by the end of 2012, with plans to expand coverage to 15 million by 2015. Several challenges must be overcome if this target is to be achieved. One of the most pertinent of these is how to fund this expansion in the current economic climate. Significant progress has already been made in reducing the cost of first-line drugs. The authors of this paper propose an alternative approach to lowering drug costs, namely dose reduction.

Evidence supporting the 600mg dose of efavirenz used in clinical practice is weak, with no difference found in the proportion of patients achieving viral suppression in the original dose finding trials of 200mg, 400mg and 600mg (unpublished). This trial in ART-naive individuals found that 400mg was non-inferior to 600mg of efavirenz in terms of viral suppression over 48 weeks of follow-up. Findings were similar when stratified by ethnic group (African, Asian, other) and body mass index, both factors which influence drug concentrations. Furthermore, fewer patients on 400mg reported adverse events which were related to efavirenz, and fewer patients with drug-related side effects on this dose stopped efavirenz. These promising results support a dose reduction strategy. However, longer term outcomes need to be evaluated and efficacy studies in patients with tuberculosis are needed before the 400mg dose is recommended for use in routine clinical practice. Certainly, if drug companies agree to manufacture this dose at scale, preferably in fixed-dose combination tablets, cost-savings could be considerable.  

Africa, Asia, Europe, Latin America
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CD4 counts at antiretroviral therapy start rising globally, but could do better!

Immunodeficiency at the start of combination antiretroviral therapy in low-,  middle-, and high-income countries.

The IeDEA and ART Cohort Collaborations. J Acquir Immune Defic Syndr 2014 Jan 1;65(1):e8-e16. doi: 10.1097/QAI.0b013e3182a39979.

Objective: To describe the CD4 cell count at the start of combination antiretroviral therapy (cART) in low-income (LIC), lower middle-income (LMIC), upper middle-income (UMIC), and high-income (HIC) countries.

Methods: Patients aged 16 years or older starting cART in a clinic participating in a multicohort collaboration spanning 6 continents (International epidemiological Databases to Evaluate AIDS and ART Cohort Collaboration) were eligible. Multilevel linear regression models were adjusted for age, gender, and calendar year; missing CD4 counts were imputed.

Results: In total, 379 865 patients from 9 LIC, 4 LMIC, 4 UMIC, and 6 HIC were included. In LIC, the median CD4 cell count at cART initiation increased by 83% from 80 to 145 cells/µL between 2002 and 2009. Corresponding increases in LMIC, UMIC, and HIC were from 87 to 155 cells/µL (76% increase), 88 to 135 cells/µL (53%), and 209 to 274 cells/µL (31%). In 2009, compared with LIC, median counts were 13 cells/µL [95% confidence interval (CI): -56 to +30] lower in LMIC, 22 cells/µL (-62 to +18) lower in UMIC, and 112 cells/µL (+75 to +149) higher in HIC. They were 23 cells/µL (95% CI: +18 to +28 cells/µL) higher in women than men. Median counts were 88 cells/µL (95% CI: +35 to +141 cells/µL) higher in countries with an estimated national cART coverage >80%, compared with countries with <40% coverage.

Conclusions: Median CD4 cell counts at the start of cART increased 2000-2009 but remained below 200 cells/µL in LIC and MIC and below 300 cells/µL in HIC. Earlier start of cART will require substantial efforts and resources globally.

Abstract access 

Editor’s notes: In this multi-cohort analysis spanning six continents, median CD4 counts at initiation of combination antiretroviral therapy were substantially higher in high-income compared to low- or middle-income countries. Median CD4 counts at initiation increased between 2002 and 2009 in most countries studied, but these increases were greater in low- and middle-income than high-income countries and were greater among men than women. Baseline CD4 counts in low- and middle-income countries were higher among countries with national antiretroviral therapy coverage of 80% or above. Nevertheless, despite the massive scale-up of antiretroviral therapy in low-income countries since 2002, the increases in median CD4 count at the start of antiretroviral therapy have been modest. Substantial efforts and resources are needed to achieve earlier implementation of antiretroviral therapy globally.

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Systematic review of supervised and unsupervised self-testing for HIV

Supervised and Unsupervised Self-Testing for HIV in High- and Low-Risk Populations: A Systematic Review.

Pant Pai N, Sharma J, Shivkumar S, Pillay S, Vadnais C, Joseph L, Dheda K, Peeling RW. PLoS Med. 2013 Apr;10(4):e1001414.doi: 10.1371/journal.pmed.1001414. Epub 2013 Apr 2.

Background: Stigma, discrimination, lack of privacy, and long waiting times partly explain why six out of ten individuals living with HIV do not access facility-based testing. By circumventing these barriers, self-testing offers potential for more people to know their sero-status. Recent approval of an in-home HIV self test in the US has sparked self-testing initiatives, yet data on acceptability, feasibility, and linkages to care are limited. We systematically reviewed evidence on supervised (self-testing and counselling aided by a health care professional) and unsupervised (performed by self-tester with access to phone/internet counselling) self-testing strategies.

Methods and Findings: Seven databases (Medline [via PubMed], Biosis, PsycINFO, Cinahl, African Medicus, LILACS, and EMBASE) and conference abstracts of six major HIV/sexually transmitted infections conferences were searched from 1st January 2000-30th October 2012. 1,221 citations were identified and 21 studies included for review. Seven studies evaluated an unsupervised strategy and 14 evaluated a supervised strategy. For both strategies, data on acceptability (range: 74%-96%), preference (range: 61%-91%), and partner self-testing (range: 80%-97%) were high. A high specificity (range: 99.8%-100%) was observed for both strategies, while a lower sensitivity was reported in the unsupervised (range: 92.9%-100%; one study) versus supervised (range: 97.4%-97.9%; three studies) strategy. Regarding feasibility of linkage to counselling and care, 96% (n = 102/106) of individuals testing positive for HIV stated they would seek post-test counselling (unsupervised strategy, one study). No extreme adverse events were noted. The majority of data (n = 11,019/12,402 individuals, 89%) were from high-income settings and 71% (n = 15/21) of studies were cross-sectional in design, thus limiting our analysis.

Conclusions: Both supervised and unsupervised testing strategies were highly acceptable, preferred, and more likely to result in partner self-testing. However, no studies evaluated post-test linkage with counselling and treatment outcomes and reporting quality was poor. Thus, controlled trials of high quality from diverse settings are warranted to confirm and extend these findings.

Abstract  Full text [free] access

Editor’s notes: The HIV self-testing agenda is gaining prominence due to a number of changing issues: the US FDA approved an oral point-of-care HIV self-test (OraQuick) for over-the-counter sale last year; international policy no longer emphasises individualised, in-depth pre-test counselling; ART is increasingly available worldwide; and the goal of universal access to treatment (Millennium Development Goal 6). These issues have reduced many of the posited barriers to self-testing, but some remain, for example, the possible psychological trauma of a positive result without immediate post-test counselling and greater difficulties in ensuring linkage to appropriate care and treatment. In general, self-testing had high acceptability and accuracy. Only one study looked at intentions to link to care, with no studies reporting actual data on linkage to care. The preferred mode and medium of counselling varied between and within study populations, suggesting a need to tailor strategies. The current lack of high quality studies on self-testing suggests an urgent need for more research on this additional route for maximising HIV testing coverage.

Africa, Asia, Europe, Northern America
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