Relationships among Substance Use, Sociodemographics, Pre-Exposure Prophylaxis (PrEP) Awareness and Related Attitudes among Young Adult Men Who Have Sex with Men.

Men who have sex with men (MSM) account for two-thirds of new HIV diagnoses. Pre-exposure prophylaxis (PrEP), a highly efficacious HIV preventive medication, is underutilized. Identifying correlates of PrEP awareness and attitudes may help increase PrEP use. Thus, we evaluated (1) PrEP awareness; (2) differences in awareness related to substance use and sociodemographics; (3) initial PrEP information sources; and (4) possible associations between information sources and PrEP-related attitudes. Young adult (ages 18-30) HIV-negative MSM from Southern U.S. undertook a web survey including questions about substance use, sexual behaviors, perceived HIV risk, and PrEP. Participants were recruited using in-person and online approaches between January 2018-January 2020. Of 506 participants, 89% were aware of PrEP. Participants with high alcohol consumption and greater perceived HIV risk had higher odds of PrEP unawareness with a trend for minority race/ethnicity. PrEP-aware participants reported high overall perceived safety, confidence in PrEP's efficacy, and low perceived difficulties with adherence though those with higher perceived HIV risk and individuals who used tobacco had less favorable attitudes. Most participants first heard about PrEP from the internet. There were no statistically significant differences in PrEP-related attitudes across initial information sources. Associations between substance use and racial/ethnic minority status and lack of PrEP awareness suggest priority subgroups for educational campaigns. Future campaigns may tailor outreach materials to the respective audience (e.g., Spanish materials for Hispanic people) and disseminate where individuals who use substances may be more likely to see them (e.g., liquor and convenience stores). Supplemental data for this article is available online at https://doi.org/10.1080/10826084.2022.2040030 .