PrEP Choice: Supporting Shared Decision Making in Pre-Exposure Prophylaxis against HIV

Harrison Fillmore, VP&S Class of 2025

Name: Harrison Fillmore
School: Vagelos College of Physicians and Surgeons, Class of 2025
Mentor: Kathrine Meyers, DrPH, MS, MPP

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With approval of long-acting injectable (LAI ) PrEP and the increased acceptability of event-driven (ED) PrEP, decision-making around PrEP initiation, switching, and persistent use has become more complex. While studies of modality preference have often focused on evaluating factors such as cost, efficacy, and logistics, a dual process model suggests that both intuitive (System 1) and deliberative (System 2) processes play a role in such decision-making. Understanding how potential and current PrEP users make decisions is essential to build clinician capacity to support their patients to choose an HIV prevention method that works for them.  We conducted 60-minute semi-structured interviews with 25 men seeking sexual healthcare at NYP’s Comprehensive HIV Program between August 2021 and May 2022. Transcribed interviews were analyzed in Dedoose using thematic analysis to identify System 1 and System 2 thought processes that influence PrEP decision-making. Participants’ mean age was 29.5, and racial/ethnic background varied, with 68% White and 32% people of color. Participants varied in both PrEP usage history (6 initiating, 5 restarting, 14 ongoing) and modality (18 daily oral; 5 ED; 2 LAI). We found evidence of both System 1 and System 2 thinking in PrEP decision-making. Common System 1 thought processes included reducing fear and anxiety, feelings of altruism and responsibility for the community, feelings of protection, peace of mind, and empowerment; System 1 thought processes that helped patients to differentiate preferences between different modalities included fear of needles, feelings around a foreign body inside of the body, feelings around spontaneity, skepticism over new technology, and the reassurance that comes with more frequent testing, medication administration, and clinic visits. Common System 2 factors regarding initiation included cost, efficacy, concerns over time spent in clinic or picking up medications, and evidence base, whereas System 2 factors influencing choice between PrEP modalities included dosing convenience, potential side effects, and ease of integration into daily routine. Different respondents evaluated these attributes differently, and respondents valued each of these factors differently.nThis research found evidence of both System 1 and System 2 thought processes that influenced decision-making in HIV pre-exposure prophylaxis; it begins to characterize both the emotional and rational responses that patients may have to different PrEP modalities. Eliciting, responding to, and leveraging System 1 factors has implications for health messaging, building provider capacity to discuss different PrEP modalities, and designing patient-facing tools to support decision-making.