Abstract
This study compares pre-exposure prophylaxis (PrEP) use among men who have sex with men (MSM) with a recent history of incarceration across various factors known to contribute to HIV transmission risk, including sexual identity, race/ethnicity, sexual activity, incarceration history, injection drug use, and internalized homophobia. We analyzed baseline lifetime PrEP use (yes or no) of 170 male-identifying participants enrolled in a randomized-controlled trial in Los Angeles County between 2019 and 2022. Using logistic regression, we assessed the association of PrEP with sexual identity, socio-demographics, and potential confounders. Compared to gay/same-gender loving-identified participants, straight/heterosexual-identified (aOR = 0.10, CI = 0.02-0.49) and bi-pansexual-identified (0.39, 0.16-0.95) participants had reduced odds of PrEP use. Black/African American-identified participants had lower odds (0.15, 0.03-0.78) of PrEP use than White-identified participants. Participants reporting 3+ years cumulative lifetime incarceration had lower odds (0.28, 0.09-0.87) of PrEP use than participants reporting <6 months. Controlling for internalized homophobia rendered differences among sexual identity groups non-significant. A similar effect was not observed for race/ethnicity and lifetime incarceration. Internalized homophobia was an important driver of PrEP use differences among MSM along the lines of sexual identity but not along the lines of race/ethnicity or cumulative incarceration.