P13.11
Background: Risk factors for HIV acquisition among young men who have sex with men (YMSM, aged 18–24 years) in Bangkok have been described. We investigated behavior associated with unprotected anal intercourse (UAI) at baseline and during follow-up visits among YMSM enrolled in the Bangkok MSM Cohort Study (BMCS).
Methods: Thai men from the Bangkok metropolitan area, aged ≥18 years who had engaged in sex with another man in the past six months were enrolled and followed up every four months. At enrollment, participants received HIV testing, and were asked about HIV-risk behaviors during the preceding four months using audio computer-assisted self-interviews. We analyzed the factors associated with UAI at baseline and over time using logistic regression and Generalized Estimating Equations (GEE), respectively.
Results: We enrolled 712 YMSM during 2006–2010, 621 (87%) contributed at least one-follow-up visit through 2013. HIV prevalence was 21%. The overall UAI at baseline was 60% and declined to less than 20% at the 36-month visit, thereafter remaining stable. For each visit increase, we found a 2% decrease in odds for reported UAI regardless of HIV infection.
A significant association with UAI at baseline was found among YMSM living with a partner [Adjusted Odd Ratio (AOR) 3.1, 95% Confidence Interval (CI) 1.7-5.6] compared with YMSM living with family. Factors associated with UAI over time were: ≥2 sexual partners (AOR 3.6, 95% CI 3.0-4.4), current HIV infection (AOR 0.5, 95% CI 0.4-0.6), club drug use (AOR 1.5, 95% CI 1.1-1.9), erectile dysfunction drug use (AOR 1.6, 95% CI 1.1-2.1), participation in group sex (AOR 1.8, 95% CI 1.5-2.2).
Conclusions: YMSM who enrolled in the BMCS exhibited a high level of UAI. The trend over time suggests that intensive HIV-risk reduction counseling and HIV testing campaigns may be associated with a significant reduction in self-reported UAI in this population. However, a longitudinal effect may limit the generalizability.
