Understanding how peer relationships influence peerdelivered HIV prevention interventions among Ugandan female sex workers: a case study from HIV self-testing

International audience; Background: Access to PrEP for men who have sex with men (MSM) is a public health priority. PrEP rollout for MSM in West Africa is confronted by unknowns concerning the feasibility in this context, due to the highly vulnerable nature of MSM (stigma, precarity, high-risk sex). We aimed to estimate the attrition rate and identify the factors associated with loss to follow-up (LTFU) in a cohort of MSM on PrEP in West Africa.Methods: Since 2017, CohMSM-PrEP has offered a comprehensive prevention package for MSM in Mali, Cote d’Ivoire, Burkina Faso, and Togo. Quarterly follow-up includes PrEP (daily or event-driven) and socio-behavioral data collection. Participants from a previous MSM cohort and new participants were enrolled. LTFU was defined as not attending the last two scheduled follow-up visits. The Kaplan-Meier technique and log-rank test were used to estimate time to LTFU and to test for significance between groups. The Cox proportional hazards regression model was used to determine predictors of LTFU and adjusted by confounders.Results: 585 participants were recruited from November 2017-January 2020. The median follow-up time was 15.6 months. During this period, 119 participants were LTFU (20%). The median follow-up time for LTFU participants was 3 months. The attrition rate was 1.8/100 person-years. Newly enrolled participants left the cohort at a higher rate than former CohMSM participants (p-value