Concurrent sexual partnerships and associated factors: a cross-sectional population-based survey in a rural community in Africa with a generalised HIV epidemic.

BACKGROUND: Although concurrent sexual partnerships may play an important role in HIV transmission in Africa, the lack of an agreed definition of concurrency and of standard methodological approaches has hindered studies. In a long-standing general population cohort in rural Uganda we assessed the prevalence of concurrency and investigated its association with sociodemographic and behavioural factors and with HIV prevalence, using the new recommended standard definition and methodological approaches. METHODS: As part of the 2010 annual cohort HIV serosurvey among adults, we used a structured questionnaire to collect information on sociodemographic and behavioural factors and to measure standard indicators of concurrency using the recommended method of obtaining sexual-partner histories. We used logistic regression to build a multivariable model of factors independently associated with concurrency. RESULTS: Among those eligible, 3,291 (66%) males and 4,052 (72%) females participated in the survey. Among currently married participants, 11% of men and 25% of women reported being in a polygynous union. Among those with a sexual partner in the past year, the proportion reporting at least one concurrent partnership was 17% in males and 0.5% in females. Polygyny accounted for a third of concurrency in men and was not associated with increased HIV risk. Among men there was no evidence of an association between concurrency and HIV prevalence (but too few women reported concurrency to assess this after adjusting for confounding). Regarding sociodemographic factors associated with concurrency, females were significantly more likely to be younger, unmarried, and of lower socioeconomic status than males. Behavioural factors associated with concurrency were young age at first sex, increasing lifetime partners, and a casual partner in the past year (among men and women) and problem drinking (only men). CONCLUSIONS: Our findings based on the new standard definition and methodological approaches provide a baseline for measuring changes in concurrency and HIV incidence in future surveys, and a benchmark for other studies. As campaigns are now widely conducted against concurrency, such surveys and studies are important in evaluating their effectiveness in decreasing HIV transmission