Search

It is important not only to collect epidemiologic data on HIV but to also fully utilize such information to understand the epidemic over time and to help inform and monitor the impact of policies and interventions. We describe and apply a novel method to estimate the size and characteristics of HIV-positive populations. The method was applied to data on men who have sex with men living in the UK and to a pseudo dataset to assess performance for different data availability. The individual-based simulation model was calibrated using an approximate Bayesian computation-based approach. In 2013, 48,310 (90% plausibility range: 39,900-45,560) men who have sex with men were estimated to be living with HIV in the UK, of whom 10,400 (6,160-17,350) were undiagnosed. There were an estimated 3,210 (1,730-5,350) infections per year on average between 2010 and 2013. Sixty-two percent of the total HIV-positive population are thought to have viral load <500 copies/ml. In the pseudo-epidemic example, HIV estimates have narrower plausibility ranges and are closer to the true number, the greater the data availability to calibrate the model. We demonstrate that our method can be applied to settings with less data, however plausibility ranges for estimates will be wider to reflect greater uncertainty of the data used to fit the model. [ABSTRACT FROM AUTHOR]

It is important not only to collect epidemiologic data on HIV but to also fully utilize such information to understand the epidemic over time and to help inform and monitor the impact of policies and interventions. We describe and apply a novel method to estimate the size and characteristics of HIV-positive populations. The method was applied to data on men who have sex with men living in the UK and to a pseudo dataset to assess performance for different data availability. The individual-based simulation model was calibrated using an approximate Bayesian computation-based approach. In 2013, 48,310 (90% plausibility range: 39,900-45,560) men who have sex with men were estimated to be living with HIV in the UK, of whom 10,400 (6,160-17,350) were undiagnosed. There were an estimated 3,210 (1,730-5,350) infections per year on average between 2010 and 2013. Sixty-two percent of the total HIV-positive population are thought to have viral load <500 copies/ml. In the pseudo-epidemic example, HIV estimates have narrower plausibility ranges and are closer to the true number, the greater the data availability to calibrate the model. We demonstrate that our method can be applied to settings with less data, however plausibility ranges for estimates will be wider to reflect greater uncertainty of the data used to fit the model.

Objective: To investigate any emerging trends in causes of death amongst HIV-positive individuals in the current cART era, and to investigate the factors associated with each specific cause of death., Design: An observational multicentre cohort study., Methods: All HIV-positive individuals included in one of the cohorts in the Data Collection on Adverse Events of Anti-HIV drugs (D:A:D) Study were included. The association between HIV-specific and non HIV-specific risk factors and death were studied using multivariable Poisson regression., Results: We observed 2482 deaths in 180,176 person-years (PY) on 33,308 individuals [rate/1000 PY = 13.8 (95% CI 13.2-14.3)]. Primary causes of death were: AIDS (n = 743; rate/1000 PY = 4.12), liver-related (341; 1.89), CVD-related (289; 1.60), non-AIDS malignancy (286; 1.59). The overall rate of death fell from 16.9 in 1999/2000 to 9.6/ 1000 PY in 2007/2008. Smoking was associated with CVD and non-AIDS cancers, HBV and HCV co-infection with liver-related deaths, and hypertension with liver-related and CVD deaths. Diabetes was a risk factor for all specific causes of death except non-AIDS cancers, and higher current HIV RNA for AIDS-related deaths. Lower CD4 cell counts were associated with a higher risk of death from all specific causes of death., Conclusion: Multiple potentially modifiable traditional and HIV-specific risk factors for death of HIV-infected persons were identified. The maximum reduction in mortality in HIV-infected populations will require that each of these factors be appropriately addressed. No trends in terms of emerging causes of unexpected deaths were observed, although monitoring will continue.

Background: Pregnancy outcomes in women receiving highly active antiretroviral treatment (HAART) in Africa are not well described., Methods: HIV-1-infected pregnant women in the ANRS Ditrame Plus and the MTCT-Plus projects were included. Between March 2001 and July 2003, when HAART was not yet available, women eligible for HAART received a short-course antiretroviral regimen, zidovudine (ZDV) or (ZDV + lamivudine) and single dose of nevirapine for preventing mother-to-child transmission (PMTCT group). Between August 2003 and August 2007, eligible women for HAART received it (HAART group). The frequencies of low birth weight (LBW) (<2500 g), stillbirth and infant mortality are reported. Risk factors associated with LBW were investigated using a logistic regression model., Results: Of the 326 HIV-infected pregnant women, 175 women received short-course antiretroviral (median CD4 cell count 177 cells/microl) and 151 received HAART (median CD4 cell count 182 cells/microl). At 12 months, three paediatric infections (2.3%) occurred in the HAART group vs. 25 (16.1%) in the PMTCT group (P < 0.001). The rate of LBW was 22.3% in the HAART group and 12.4% in the PMTCT group (P = 0.02). In multivariable analysis (n = 309), after adjustment on maternal CD4 cell count, WHO stage, age and maternal BMI, HAART initiated before pregnancy [adjusted odds ratio (OR) 2.88, 95% confidence interval (CI) 1.10-7.51] and during pregnancy (adjusted OR 2.12, 95% CI 1.15-4.65) and maternal BMI at delivery (adjusted OR 2.43, 95% CI 1.20-4.91) were associated with LBW., Conclusion: HAART in pregnant African women with advanced HIV disease substantially reduced mother-to-child transmission, but was associated with LBW.