Social and Behavioral Correlates of Sexually Transmitted Infections among Men who Have Sex with Men who Use Alcohol in the San Francisco Bay Area.

The risk of acquiring sexually transmitted infections (STIs) among men who have sex with men (MSM) is driven by various socio-behavioral factors. From 2015-2017, 247 MSM ≥ 18 years-old who reported alcohol use in the past year, were recruited into a cross-sectional study in San Francisco. Participants completed a survey assessing socio-demographics, substance use and treatment, sexual behaviors, HIV status and self-reported STI diagnosis in the past 6 months. Multivariable logistic regression models stratified by HIV status were used to identify the correlates of STIs. Of 247 MSM, the prevalence of bacterial STIs were: gonorrhea (12.9%), chlamydia (9.3%) and syphilis (6.0%). Among 177 MSM living without HIV, factors significantly associated with recent STI diagnosis were: current pre-exposure prophylaxis (PrEP) use (aOR = 3.53, 95% CI: 1.42-8.75, ≤ .01), popper use during sex in the past 6 months (aOR = 3.16, 95% CI = 1.34-7.47, ≤ .01) and a history of alcohol treatment (aOR = 0.17, 95% CI = 0.04-0.68, = .01). Also, in a sensitivity analysis (removing PrEP), any receptive condomless anal sex was independently associated with recent STI diagnosis (aOR = 2.86, 95% CI = 1.15-7.08, = .02). Among 70 MSM living with HIV, factors significantly associated with recent STI diagnosis were: White race/ethnicity (adjusted odds ratio [aOR] = 7.36, 95% confidence interval [CI] = 1.48-36.62, = .01), younger age (aOR = 0.90, 95% CI: 0.84-0.97, < .01) and a higher number of male sexual partners in the past 6 months (aOR = 1.03, 95% CI = 1.00-1.06, = .02). Sexual health interventions that address the unique needs of MSM living with and without HIV who use alcohol in San Francisco are needed to reduce STI acquisition and transmission.