Sociodemographic Characteristics of HIV Pre-Exposure Prophylaxis Use and Reasons for Nonuse Among Gay, Bisexual, and Other Men Who Have Sex with Men from Three US Cities.

HIV pre-exposure prophylaxis (PrEP) is a preventive medication that could reduce new infections among men who have sex with men (MSM). There are limited data on differing reasons for PrEP nonuse by condomless anal sex (CAS). We examined demographic and behavioral variables associated with PrEP use and reasons for PrEP nonuse by CAS. Data are from the M-cubed Study, collected in a 2018 baseline assessment of MSM ( n  = 798) in Atlanta, Detroit, and New York City. Participants reported current PrEP use (31%), previous use (8%), and never use (61%). MSM reporting CAS [adjusted odds ratio (aOR) = 2.60, confidence interval (95% CI) = 1.73-3.91], age 18-29 (aOR = 2.11, 95% CI = 1.26-3.52), 30-39 (aOR = 2.12, 95% CI = 1.25-3.59), with a college degree (aOR = 1.96, 95% CI = 1.20-3.21), or postgraduate education (aOR = 2.58, 95% CI = 1.51-4.40) had greater odds of current (vs. never) use; uninsured (aOR = 0.30, 95% CI = 0.16-0.57) men had lower odds of current (vs. never) use. For never use, more MSM who reported CAS (vs. did not) endorsed the following reasons ( p' s < 0.05): Insurance wouldn't cover PrEP (20% vs. 12%) , Didn't know where to get it (33% vs. 24%) and fewer reported Didn't need PrEP (23% vs. 39%) and Started a committed relationship (7% vs. 25%) . For discontinuation, more MSM who reported CAS (vs. did not) endorsed Worry about the safety of PrEP (19% vs. 3%). Efforts are needed to enhance PrEP as an option among older, less educated, and uninsured MSM. These findings may inform how providers can facilitate PrEP use by messaging on access and safety for MSM who reported CAS.