Misclassification of sexual health risks in a self-identified low risk cohort of men who have sex with men (MSM) enrolled in a community based PrEP program

BACKGROUND: The CDC recommends PrEP for MSM at substantial risk of HIV acquisition, leaving clinicians unsure whether to prescribe PrEP to MSM who do not disclose HIV risk factors. In a real-world setting we followed a cohort of MSM using PrEP who during their clinical visits stated they were low-risk for HIV to assess the accuracy of their HIV risk perception. METHODS: A longitudinal cohort of MSM requesting PrEP despite reporting either 100% condom use or participation in oral sex only was followed over 13 months at a community clinic in San Francisco. Participants completed a sexual and substance use behavior questionnaire at baseline, followed by quarterly HIV/STI testing and condom use change questionnaires. RESULTS: 81 clients self-identified as low-risk for HIV (age range 22-71, 83% non-Hispanic, 17% Hispanic). The mean number of partners in the previous 12 months was 10. 80% of MSM who perceived themselves as low-risk for HIV reported at least one HIV-related risk behavior including, sex while intoxicated (38%), sex with a person of unknown HIV status (28%), injecting drugs (1%), consuming 5 or more alcoholic drinks at one sitting (40%), ecstasy (11%), and poppers (16%). Condomless sex increased to 12% at month 1, peaked at 22% at month 7, and then decreased to 6% at month 10 before increasing slightly to 8% at month 13. Rates of pharyngeal GC/CT varied from 7% at baseline to 11% at month 13, while rectal GC/CT decreased from 6% at baseline to 0% at month 13. The rate of syphilis was 1% both at baseline and at month 13, however, 11% and 15% of clients tested positive for syphilis at months 1 and 7 respectively. CONCLUSIONS: 80% of participants who perceived themselves as low risk for HIV were actually high risk. Clients’ failure to report risk factors for HIV acquisition may lead to an increasingly unacceptable proportion of unidentified MSM at risk of HIV.