Loss to Follow-Up and Re-Engagement in HIV Pre-Exposure Prophylaxis Care in the United States, 2013-2019.

Retention in HIV pre-exposure prophylaxis (PrEP) care is critical for effective PrEP implementation. Few studies have reported long-term lost to follow-up (LTFU) and re-engagement in PrEP care in the United States. Medical record data for all cisgender patients presenting to the major Rhode Island PrEP clinic from 2013 to 2019 were included. LTFU was defined as no PrEP follow-up appointment within 98 days. Re-engagement in care was defined as individuals who were ever LTFU and later attended a follow-up appointment. Recurrent event survival analysis was performed to explore factors associated with PrEP retention over time. Of 654 PrEP patients, the median age was 31 years old [interquartile range (IQR): 25, 43]. The majority were male (96%), White (64%), non-Hispanic (82%), and insured (97%). Overall, 72% patients were ever LTFU and 27% of those ever LTFU re-engaged in care. Female patients were 1.37 times [crude hazard ratio (cHR): 1.37; 95% confidence interval (CI): 0.86-2.18] more likely to be LTFU than male patients, and a 1-year increase in age was associated with a 1% lower hazard of being LTFU (cHR: 0.99; CI: 0.98-0.99). Being either heterosexual (aHR: 2.25, 95% (CI): 1.70-2.99] or bisexual (aHR: 2.35, 95% CI: 1.15-4.82) was associated with a higher hazard of loss to follow-up compared with having same-sex partners only. The majority of PrEP users were LTFU, especially at the first 6 months of PrEP initiation. Although a significant number were re-engaged in care, targeted interventions are needed to improve retention in PrEP care. This study characterized the natural projection of loss to follow-up and re-engagement in HIV PrEP care using a longitudinal clinic cohort data and explored associated factors for guiding future interventions to improve retention in PrEP care.