P3.124Risk Factors For HIV Infection Among Men Who Have Sex with Men in Seven Cities in Colombia Using Respondent-Driven Sampling

BackgroundMen who have sex with men (MSM) are increasingly recognised as the principal core group for HIV transmission in Latin America. In Colombia, factors associated with HIV infection have not previously been assessed.MethodsA secondary analysis was conducted using data from a bio-behavioural surveillance study among 2567 MSM ages 18 and older, recruited using respondent-driven sampling from seven cities in Colombia in 2010 (N = 333 to 488 across cities). The study used a face-to-face survey and biological testing to assess risk behaviours and HIV infection. Factors with a bivariate association with infection were estimated from the pooled sample using a multilevel logistic regression framework, including random effects for recruitment tree and immediate recruiter, fixed effects to control for unobserved differences across cities, recruiter-level controls to account for recruitment patterns, and probability weights to account for differential personal and city-level estimated network size.ResultsEstimated HIV prevalence ranged from 5.8% in Pereira (95% confidence interval [CI] 2.7%-9.5%) to 23.7% in Cali (CI 17.6%-29.9%). Recruiter's HIV infection was moderately related to participant's HIV infection (OR = 1.5, CI = 0.9-2.5, P = 0.091). Clustering by recruiter, recruitment tree, and city explained 10%,10% and 2% of variance in the HIV outcome, respectively. Factors associated with HIV (P less than or equal to 5%) included age greater than or equal to 40 (OR = 2.9) and 25-39 years (OR = 2.5) compared to 18-24 years, meeting casual sex partners at saunas (OR = 2.6), previous sexually transmitted infection (STI) (OR = 2.1), current employment (OR = 1.9) and age of sexual debut < 18 years (OR = 1.4).ConclusionThe distribution of HIV infection among MSM in Colombia's largest cities suggests an ageing epidemic. HIV testing and prevention interventions should be intensified, target MSM at highest risk as well as younger age groups and STI infection to stem transmission early. Future analysis of this sample should also control for the hierarchical sampling structure and recruitment patterns.