Predictors of day-level sexual risk for young gay and bisexual men.

As HIV infection rates remain high among young gay and bisexual men, investigations into determinants of sexual risk are paramount. This study examined independent and interactive effects of substance use, mental health, perceived benefits of unprotected sex, and type of sex partner on odds of not using condoms. Analyses included 188 high-risk substance using HIV-negative and unknown status young gay and bisexual men (ages 18-29). Substance use and endorsing favorable attitudes towards unprotected sex strongly predicted sexual risk. Mental health moderated the relationship between partner type (main vs. casual) and condom use such that increased anxiety and depression were associated with increased odds of using condoms with main partners and not using condoms with casual partners. Understanding how these determinants of HIV risk converge to predict unprotected anal sex can identify essential risk relationships for prevention, obtain effects sizes of greater magnitude and prolonged sustainability, and build robust couples-based interventions.