HIV Preexposure Prophylaxis Uptake Among US Youth in a National Claims Database

Importance: Youths aged 13 to 24 years remain significantly underrepresented among users of HIV preexposure prophylaxis (PrEP). Understanding factors associated with PrEP initiation in this population is essential to inform strategies to reduce HIV transmission. Objective: To identify demographic, geographic, and clinician-related factors associated with PrEP initiation among youths aged 13 to 21 years who could benefit from PrEP. Design, Setting, and Participants: This retrospective cohort study used administrative claims data from the Merative MarketScan Commercial Claims and Encounters Database from January 1, 2018, to December 31, 2022. This national, population-based sample included commercially insured youths aged 13 to 21 years in the US who may benefit from PrEP, defined by ICD-10 codes for high-risk sexual behavior or bacterial sexually transmitted infections, including gonorrhea, chlamydia, and syphilis. Participants were followed up from the date of PrEP indication until PrEP prescription fill, insurance disenrollment, or HIV diagnosis. Data were analyzed between April 2024 and February 2025. Exposures: Demographic and clinical characteristics (age, sex, mental health, and substance use diagnoses), geographic region, and state-level variables (privacy laws, LGBTQ+ protections). Main Outcomes and Measures: Cox proportional hazards models were used to estimate adjusted hazard ratios (aHRs) for PrEP initiation, and Kaplan-Meier curves were generated to assess time to PrEP receipt. Results: Among 100 536 youths (71.2% female; mean [SD] age, 18.8 [1.9] years), 1598 filled a PrEP prescription during the follow-up period, corresponding to an incidence rate of 6.9 per 1000 person-years (95% CI, 6.5-7.2 person-years). PrEP receipt was more likely among males (aHR, 15.6; 95% CI, 13.5-18.1) and older youths (aHR, 3.38; 95% CI, 2.83-4.03 for ages 20-21 vs <18 years). Youths in the South (aHR, 0.69; 95% CI, 0.60-0.80) and Midwest (aHR, 0.74; 95% CI, 0.63-0.87) had a lower likelihood of PrEP initiation compared with those in the Northeast. Presence of state-level LGBTQ+ protective laws was associated with higher PrEP uptake (aHR, 1.36; 95% CI, 1.23-1.52). Pediatricians documented conditions suggesting a potential benefit from PrEP in 141 of the 1598 youths who filled a prescription (8.8%) but accounted for only 76 of the documented filled PrEP prescriptions (4.8%). Conclusions and Relevance: In this cohort study, PrEP uptake among adolescents and young adults remained strikingly low, particularly among minors, females, and youths residing in the South. Efforts to expand PrEP use among youths should address geographic disparities, legal and policy barriers, and clinician engagement to improve equitable access to HIV prevention.