Functional Knowledge of Pre-Exposure Prophylaxis for HIV Prevention Among Participants in a Web-Based Survey of Sexually Active Gay, Bisexual, and Other Men Who Have Sex With Men: Cross-Sectional Study

Abstract

Background: Awareness of pre-exposure prophylaxis (PrEP) for HIV prevention is increasing, but little is known about the functional knowledge of PrEP and its impact on willingness to use PrEP.

Objective: The objective of this study was to assess the functional knowledge of PrEP among a sample of gay, bisexual, and other men who have sex with men (MSM) participating in a Web-based survey of sexually active MSM.

Methods: Men at least 18 years old, residing in the United States, and reporting sex with a man in the previous 6 months were recruited through social networking websites. PrEP functional knowledge included the following 4 questions (1) efficacy of consistent PrEP use, (2) inconsistent PrEP use and effectiveness, (3) PrEP and condom use, and (4) effectiveness at reducing sexually transmitted infections (STIs). Ordinal logistic regression was used to identify respondent characteristics associated with PrEP functional knowledge. In a subsample of participants responding to HIV prevention questions, we compared willingness to use PrEP by response to PrEP functional knowledge using logistic regression analysis adjusted for age, race and ethnicity, and education level.

Results: Among 573 respondents, PrEP knowledge was high regarding adherence (488/573, 85.2%), condom use (532/573, 92.8%), and STIs (480/573, 83.8%), but only 252/573 (44.0%) identified the correct efficacy. Lower functional PrEP knowledge was associated with minority race/ethnicity (P=.005), lower education (P=.01), and not having an HIV test in the past year (P=.02). Higher PrEP knowledge was associated with willingness to use PrEP (P=.009). Younger age was not associated with higher PrEP functional knowledge or willingness to use PrEP.

Conclusions: PrEP knowledge was generally high in our study, including condom use and consistent use but may be lacking in higher risk MSM. The majority of respondents did not correctly identify PrEP efficacy with consistent use, which could impact motivation to seek out PrEP for HIV prevention. Targeted messaging to increase PrEP knowledge may increase PrEP use.

Keywords: human immunodeficiency virus; men who have sex with men; pre-exposure prophylaxis (PrEP).

Figure 1

Pre-exposure prophylaxis (PrEP) functional knowledge questions, Prioritizing U, 2015.

Figure 2

The percentage distribution of correct responses to pre-exposure prophylaxis (PrEP) functional knowledge questions by all respondents and respondents reporting current PrEP use, Prioritizing U, 2015. The percentage distribution of correct responses by full sample of respondents (orange) and by respondents reporting current PrEP use (blue), and percentage of correct responses for the four PrEP knowledge questions, percentage with any of the four PrEP knowledge questions, and percentage of respondents with correct responses for all four PrEP knowledge questions.