Dataset Information

The dual impact of antiretroviral therapy and sexual behaviour changes on HIV epidemiologic trends in Uganda: a modelling study.

ABSTRACT:

Objectives

Antiretroviral therapy (ART) availability in a population may influence risky sexual behaviour. We examine the potential impact of ART on the HIV epidemic, incorporating evidence for the impact that ART may have on risky sexual behaviour.

Methods

A mathematical model, parameterised using site-specific data from Uganda and worldwide literature review, was used to examine the likely impact of ART on HIV epidemiologic trends. We varied assumptions about rates of initiating ART, and changes in sexual partner turnover rates.

Results

Modelling suggests that ART will reduce HIV incidence over 20 years, and increase prevalence. Even in the optimistic scenario of ART enrollment beginning after just five months of infection (in HIV stage 2), prevalence is estimated to rise from a baseline of 10.5% and 8.3% among women and men, respectively, to at least 12.1% and 10.2%, respectively. It will rise further if sexual disinhibition occurs or infectiousness while on ART is slightly higher (2% female to male, rather than 0.5%). The conditions required for ART to reduce prevalence over this period are likely too extreme to be achievable. For example, if ART enrolment begins in HIV stage 1 (within the first 5 months of infection), and if risky sexual behaviour does not increase, then 3 of our 11 top fitting results estimate a potential drop in HIV prevalence by 2025. If sexual risk taking rises, it will have a large additional impact on expected HIV prevalence. Prevalence will rise despite incidence falling, because ART extends life expectancy.

Conclusions

HIV prevalence will rise. Even small increases in partner turnover rates will lead to an additional substantial increase in HIV prevalence. Policy makers are urged to continue HIV prevention activities, including promoting sex education, and to be prepared for a higher than previously suggested number of HIV infected people in need of treatment.

SUBMITTER: Shafer LA

PROVIDER: S-EPMC4112492 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The dual impact of antiretroviral therapy and sexual behaviour changes on HIV epidemiologic trends in Uganda: a modelling study.

Shafer Leigh Anne LA Nsubuga Rebecca N RN Chapman Ruth R O'Brien Katie K Mayanja Billy N BN White Richard G RG

Sexually transmitted infections 20140224 5

<h4>Objectives</h4>Antiretroviral therapy (ART) availability in a population may influence risky sexual behaviour. We examine the potential impact of ART on the HIV epidemic, incorporating evidence for the impact that ART may have on risky sexual behaviour.<h4>Methods</h4>A mathematical model, parameterised using site-specific data from Uganda and worldwide literature review, was used to examine the likely impact of ART on HIV epidemiologic trends. We varied assumptions about rates of initiating ...[more]

PMID: 24567521

Similar Datasets

Project description:BackgroundA decline in mortality rates during the first 12 months of antiretroviral therapy (ART) has been mainly linked to increased ART initiation at higher CD4 counts and at less advanced World Health Organization (WHO) clinical stages of HIV infection; however, the role of improved patient care has not been well studied. We estimated improvements in early mortality due to improved patient care.MethodsWe conducted a retrospective cohort study of HIV-infected individuals ages 18 and older who initiated ART at the Mengo HIV Counseling and Home Care Clinic between 2006 and 2016. We conducted a mediation analysis using generalized structural equation models with inverse odds ratio weighting to estimate the natural direct and indirect effects of ART initiation time on early mortality.FindingsAmong 6,847 patients, most were female (69%), with a median age of 32 (interquartile range [IQR] = 28-38), versus a median age of 38 (IQR = 32-45) for males. The median CD4 count at ART initiation increased from 142 cells/ul (95% confidence interval [CI] = 135-150) in 2006-2010 to 302 cells/ul (95% CI = 283-323) in 2015-2016 (p < 0·001). The number of patients at WHO clinical stages I/II increased from 52% in 2006-2010 to 78% in 2015-2016 (p < 0·001). Annual early mortality decreased from 8·8 deaths/100 person years (PYS) in 2006 to 2.5 deaths/100 pys in 2016 (p < 0·001). Mediation by CD4 counts and WHO clinical stages accounted for 54% of the total effect of ART initiation timing on early mortality. In comparison, 46% remained as the direct effect, reflecting the contribution of improved patient care.InterpretationImproved patient care practices should be promoted as a strategy for reducing early mortality after ART initiation, above and beyond the effects from ART initiation at higher CD4 counts and less advanced WHO clinical stage alone.FundingThis research was supported by the President's Emergency Plan for AIDS Relief (PEPFAR), the National Institute of Allergy and Infectious Diseases Division of Intramural Research, and the National Cancer Institute.

Project description:Scarce data are available to assess sexual behaviour of individuals using antiretroviral pre-exposure prophylaxis for HIV prevention. Increased sexual risk taking by individuals using effective HIV prevention strategies, like pre-exposure prophylaxis, could offset the benefits of HIV prevention. We studied whether the use of pre-exposure prophylaxis in HIV-uninfected men and women in HIV-serodiscordant couples was associated with increased sexual risk behaviour.We undertook a longitudinal analysis of data from the Partners PrEP Study, a double-blind, randomised, placebo-controlled trial of daily oral pre-exposure prophylaxis among HIV-uninfected partners of heterosexual HIV-serodiscordant couples (n=3163, ?18 years of age). Efficacy for HIV prevention was publicly reported in July 2011, and participants continued monthly follow-up thereafter. We used regression analyses to compare the frequency of sex-unprotected by a condom-during the 12 months after compared with the 12 months before July 2011, to assess whether knowledge of pre-exposure prophylaxis efficacy for HIV prevention caused increased sexual risk behaviour.We analysed 56?132 person-months from 3024 HIV-uninfected individuals (64% male). The average frequency of unprotected sex with the HIV-infected study partner was 59 per 100 person-months before unmasking versus 53 after unmasking; we recorded no immediate change (p=0·66) or change over time (p=0·25) after July, 2011. We identified a significant increase in unprotected sex with outside partners after July, 2011, but the effect was small (average of 6·8 unprotected sex acts per year vs 6·2 acts in a predicted counterfactual scenario had patients remained masked, p=0·04). Compared with before July, 2011, we noted no significant increase in incident sexually transmitted infections or pregnancy after July, 2011.Pre-exposure prophylaxis, provided as part of a comprehensive prevention package, might not result in substantial changes in risk-taking sexual behaviour by heterosexual couples.The Bill & Melinda Gates Foundation and the US National Institute of Mental Health.

Project description:INTRODUCTION:Risk reduction towards safer behaviour is promoted after enrolment in HIV prevention trials. We evaluated sexual behaviour, changes in sexual behaviour and factors associated with risky behaviour after one-year of follow-up among women enrolled in HIV prevention trials in Northern Tanzania. METHODS:Self-reported information from 1378 HIV-negative women aged 18-44 enrolled in microbicide and vaccine feasibility studies between 2008-2010,was used to assess changes in behaviour during a 12-month follow-up period. Logistic regression with random intercepts was used to estimate odds ratios for trends in each behaviour over time. A behavioural risk score was derived from coefficients of three behavioural variables in a Poisson regression model for HIV incidence and thereafter, dichotomized to risky vs less-risky behaviour. Logistic regression was then used to identify factors associated with risky behaviour at 12 months. RESULTS:At baseline, 22% reported multiple partners, 28% were involved in transactional sex and only 22% consistently used condoms with non-regular partners. The proportion of women reporting multiple partners, transactional sex and high-risk sex practices reduced at each 3-monthly visit (33%, 43% and 47% reduction in odds per visit respectively, p for linear trend <0.001 for all), however, there was no evidence of a change in the proportion of women consistently using condoms with non-regular partners (p = 0.22). Having riskier behaviours at baseline, being younger than 16 years at sexual debut, having multiple partners, selling sex and excessive alcohol intake at baseline were strongly associated with increased odds of risky sexual behaviour after 12 months (p<0.005 for all). CONCLUSION:An overall reduction in risky behaviours over time was observed in HIV prevention cohorts. Risk reduction counselling was associated with decreased risk behaviour but was insufficient to change behaviours of all those at highest risk. Biological HIV prevention interventions such as PrEP for individuals at highest risk, should complement risk reduction counselling so as to minimize HIV acquisition risk.

Dataset Information

The dual impact of antiretroviral therapy and sexual behaviour changes on HIV epidemiologic trends in Uganda: a modelling study.

Objectives

Methods

Results

Conclusions

Publications

The dual impact of antiretroviral therapy and sexual behaviour changes on HIV epidemiologic trends in Uganda: a modelling study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure