Pre-exposure prophylaxis uptake among users of non-occupational post-exposure prophylaxis: a longitudinal analysis of attendees at a large sexual health clinic in Montréal

AbstractBackgroundReducing HIV transmission using pre-exposure prophylaxis (PrEP) requires targeting individuals at high acquisition risk, such as men who have sex with men (MSM) with a history of non-occupational post-exposure prophylaxis (nPEP). This study aims to characterize longitudinal trends in PrEP uptake and its determinants among nPEP users in Montréal.MethodsEligible attendees at Clinique médicale l’Actuel were recruited prospectively starting in October 2000 (nPEP) and January 2013 (PrEP). Linking these cohorts, we characterized the PEP-to-PrEP cascade, examined the determinants of PrEP uptake after nPEP consultation using a Cox proportional-hazard model, and assessed whether PrEP persistence differed by nPEP history using Kaplan-Meier curves.ResultsAs of August 2019, 31% of 2,682 MSM nPEP cohort participants had two or more nPEP consultations. Subsequent PrEP consultations occurred among 36% of nPEP users, of which 17% sought nPEP again afterwards. Among 2,718 PrEP cohort participants, 46% reported previous nPEP use. Among nPEP users, those aged 25-49 years (Hazard Ratio (HR)=1.3, 95% confidence interval (CI): 1.1-1.7), with more nPEP episodes (HR=1.4, 95%CI: 1.3-1.5), reported chemsex (HR=1.3, 95%CI: 1.1-1.7), with a STI history (HR=1.5; 95%CI: 1.3-1.7), and who returned for their first nPEP follow-up visit (HR=3.4, 95%CI: 2.7-4.2) had higher rates of PrEP linkage. There was no difference in PrEP persistence between PEP-to-PrEP and PrEP only participants.ConclusionOver one-third of nPEP users were subsequently prescribed PrEP. However, the large proportion of men who repeatedly use nPEP calls for more efficient PrEP-linkage services and, among those that use PrEP, improved persistence should be encouraged.