(P299) Association of provider type with sexually transmitted infection (STI) occurrence and pre-exposure prophylaxis (PrEP) non-adherence among key adolescent populations in Brazil

Background: Key adolescent populations (KAP), including sexual minority men and transgender women aged 15-19 years, account for an increasing share of new HIV diagnoses globally. The PrEP1519 study in Brazil is one of the first and largest prospective, multicenter PrEP demonstration cohort studies among KAP. In Brazil, both nurses and physicians prescribe PrEP, but it is unclear if provider differences impact PrEP care. We leveraged the PrEP1519 cohort to examine the association of provider type with STI occurrence and PrEP non-adherence.

Methods: We included KAP prescribed oral PrEP from 2019-2021 in three Brazilian cities: São Paulo, Salvador, and Belo Horizonte. Visits occurred at baseline, 30, 60 days and then quarterly. At each visit, we conducted STI laboratory tests (chlamydia, gonorrhea, syphilis, and M. genitalium) and assessed adherence by medication possession ratios (MPR). We defined three provider type groups for PrEP visits: majority (≥66%) physicians, majority nurses, and mixed (no dominant provider type). We described the proportions of KAP with ≥1 bacterial STI and with mean MPR < 0.53 (non-adherence) and used generalized estimating equations logistic regression to compare the odds of these outcomes by provider type, adjusting for sociodemographic and behavioral confounders.



Results: Of 1216 adolescents, 298, 755, and 163 were prescribed PrEP from nurses, physicians, and mixed providers, respectively. Most were aged 18-19 (72.0%), male (85.3%), and black/brown race (66.9%). STIs occurred for 12.8%, 13.4%, and 20.9% of adolescents in nurse, physician, and mixed groups, respectively, and mean MPR < 0.53 occurred for 49.0%, 36.2%, and 31.3%. In adjusted analyses, adolescents prescribed PrEP from nurses vs physicians were more likely to have ≥1 STI (aOR 1.66 [95% CI: 1.03-2.67]) but had similar odds of MPR< 0.53 (aOR 1.17 [95% CI: 0.79-1.75]). Adolescents prescribed PrEP from mixed providers vs nurses or physicians were also more likely to have ≥1 STI, but they were less likely to have MPR< 0.53 (Figure).

Conclusion: Provider type was not associated with PrEP non-adherence among KAP in Brazil, supporting provision of PrEP by both nurses and physicians. However, STI prevalence was high, and adolescents may benefit from additional interventions to prevent STIs, especially when a physician is not available.