Day Level Associations between Sexual Risk and Drug Use Among Emerging Adult Gay and Bisexual Men

Background: Although studies have found significant relationships between substance use and unprotected sex, few have examined day-level relationships which are better suited to telling whether sexual risk behavior occurs in the context of substance use. Methods: We examined day-level substance use, mental health (anxiety and depression) and perceived benefits of unprotected sex predict unprotected anal sex acts with main and casual partners in 188 HIV-negative emerging adult (ages 18-29) gay and bisexual men (EAGBM). Results: Any individual drug used increased the odds of not using a condom on a sex day (OR = 2.15). Perceived benefits of unprotected sex were significantly associated with not using a condom on a sex day (OR = 1.08). The interaction between having a main partner sex day and depression/anxiety predicted not using a condom (OR = 0.15), such that for those having sex with their main partner on a given day, the odds of not using a condom decreased, as general depression/anxiety increased. Perceived benefits of unprotected sex did not significantly interact with having sex with a main partner (OR = 2.01), but maintained a constant independent effect on the odds of not using a condom (OR = 1.93). Conclusions: Substance use predicted high risk sex at all levels of participants' depression, anxiety or type of sex partner. Perceived benefits of unprotected sex was predictive of unprotected sex, above and beyond substance use. Increased anxiety/depression was predictive of condom use with main partners. These factors need continued attention in developing HIV interventions for EAGBM.