Pre-exposure prophylaxis adherence and risks of HIV and sexually transmitted infection among adult men before vs during the COVID-19 pandemic

BACKGROUND: The COVID-19 pandemic disrupted HIV prevention services, including reductions in pre-exposure prophylaxis (PrEP) prescription and HIV testing. However, evidence on the association between the pandemic with PrEP use, as well as HIV and sexually transmitted infection (STI) rates among PrEP users remained limited. OBJECTIVE: To compare patterns of PrEP adherence, HIV incidence, and STI rates among adult men newly initiating PrEP before vs during the COVID-19 pandemic. METHODS: We conducted a new-user retrospective cohort analysis of commercially insured PrEP users using the 2018-2021 MarketScan administrative claims database. Adult men aged 18-49 years in the MarketScan administrative claims database prescribed tenofovir disoproxil fumarate with emtricitabine or tenofovir alafenamide with emtricitabine for PrEP were included. Group-based trajectory modeling was used to identify PrEP adherence patterns. After balancing group demographic and clinical characteristics with inverse probability treatment weighting, time-varying Cox proportional hazards models were used to evaluate HIV risk and Poisson regression was used to assess STI rates. RESULTS: Of 8,683 adult men (43% aged 25 to 34 years), 5,957 initiated PrEP before the pandemic and 2,726 during the pandemic. Prepandemic adherence trajectories included nonadherence (11.8% of the cohort) and rapidly declining (20.8%), gradually declining (21.1%), and consistently high (46.3%) adherence. Pandemic adherence trajectories included early discontinuation (35.7%) and rapidly declining (19.5%), gradually declining (14.8%), and consistently high (29.9%) adherence. Initiating PrEP during the pandemic was associated with higher risk of HIV acquisition (adjusted hazard ratio = 2.20 [95% CI = 1.08-4.47]). STI rates did not differ between groups (adjusted incidence rate ratio = 1.04 [95% CI = 0.88-1.23]). CONCLUSIONS: Individuals initiating PrEP during the pandemic were associated with reduced PrEP adherence and higher HIV incidence. Targeted strategies to maintain access and continuity of HIV prevention services during public health emergencies are needed.