Abstract
BACKGROUND: Pre-exposure prophylaxis (PrEP) is a highly effective HIV prevention strategy yet use and persistence among populations at high vulnerability to HIV in Brazil remains suboptimal. We sought to quantify internalized homonegativity and discrimination using multi-item validated instruments and to estimate their associations with PrEP use and discontinuation among gay, bisexual, and other men who have sex with men (MSM). METHODS: A cross-sectional, web-based survey was conducted from November 2021 to January 2022, recruiting a convenience sample of MSM through dating apps and social media. The survey assessed sociodemographic characteristics, sexual behavior, substance use, HIV transmission knowledge (using the HIV Knowledge Assessment tool), internalized homonegativity (using the Reactions to Homosexuality Scale), and experiences of discrimination (using the Explicit Discrimination Scale). PrEP use was assessed with response options "I have never used PrEP" (henceforth "never used"), "I am currently using PrEP" (henceforth "current use"), and "I used PrEP in the past but stopped" (henceforth "discontinuation"). Unadjusted and adjusted associations between internalized homonegativity and discrimination and the outcomes a) "current use" of PrEP compared to "never use", and b) "discontinuation" compared to "current use", were estimated using logistic regression models. RESULTS: The analytic sample consisted of 2,840 participants, with PrEP use patterns distributed as follows: 71.3% had never used PrEP, 22.8% were current users, and 5.9% had discontinued use. Unadjusted analyses indicated negative associations between internalized homonegativity and discrimination scores with current PrEP use (with higher scores leading to decreased odds of "current use"), and positive associations with PrEP discontinuation (higher scores leading to increased odds of "discontinuation"). After adjusting for potential confounders, higher internalized homonegativity was associated with decreased odds of "current use" (adjusted odds ratio [aOR] = 0.88, 95% confidence interval [CI] = 0.78-0.99) per 1 standard deviation [SD] increase in score) and more experiences of discrimination was associated with increased odds of "discontinuation" (aOR = 1.24, 95% CI: 1.03-1.50 per 1 SD increase in score). DISCUSSION: Our findings support the hypothesis that psychological distress from self-stigmatization and discrimination undermines PrEP use and persistence. Public health strategies need to integrate stigma-reduction and culturally competent, LGBTQIAPN+-affirming services to support PrEP as an effective prevention strategy.