Unprotected anal intercourse and substance use among men who have sex with men with recent HIV infection

Objectives: To examine within-subjects and combined between-and within-subjects associations between substance use and unprotected anal intercourse (UAI) among men who have sex with men (NISM) with recent HIV infection. Methods: One hundred ninety-four MSM who were recently infected with HIV completed a computer-assisted questionnaire regarding sexual behaviors and substance use with their last 3 partners. Associations between UAI and substance use were assessed using conditional logistic regression (CLR) to assess associations among the 116 MSM reporting UAI with some but not all partners and generalized linear mixed effects models (GLMMs) to examine a combination of within- and between-subjects associations in the entire sample (N = 194). Results: In multivariate CLR models and GLMMs, UAI was associated with the use of methamphetamine (odds ratio [OR] 4.9 and OR = 3.5, respectively), marijuana (OR = 4.0 and OR 2.2, respectively) and erectile dysfunction medications (EDMs) when used with a main partner (OR 13.8 and OR = 10.1, respectively). Conclusions: Results indicate that a direct association may exist between specific substances and UAI and provide evidence that the use of methamphetamine and EDMs may contribute to HIV transmission.