Exploring definitions of retention in care for people living with HIV in the United States in the modern treatment era

Objective: To describe retention in HIV care based on various definitions of retention in the modern treatment era. Design: A cohort study of people enrolled in care at seven mostly urban HIV clinics across the United States, 2010 - 2018. Methods: We estimated retention based on missed visits, kept visits, kept encounters (clinical visits, CD4^þ cell counts, and viral loads), and HIV labs. We contrasted risk factors for retention by different definitions and estimated odds ratios for viral suppression and hazard ratios for mortality in 2 years immediately following the year in which retention was defined (the study year). Results: Across 108 171 person-years (N ¼ 21 481 people), in 71% of years, people kept ≥75% of scheduled visits; in 78%, people kept ≥2 visits >90 days apart; in 74%, people had ≥2 HIV labs >90 days apart; and in 47%, people had no gaps >6 months in clinic visits. Missing >25% of scheduled visits despite attending ≥2 visits >90 days apart was associated with nonwhite non-Hispanic race/ethnicity, history of injection drug use, and prior AIDS diagnosis. In contrast, attending ≥75% of scheduled visits while not attending ≥2 visits >90 days apart was associated with male sex, white race, no injection drug use history, and no prior AIDS diagnosis. Subsequent viral nonsuppression was more strongly associated with missed- than kept-visit measures of retention; 2-year mortality was only associated with failure to be retained by missed-visit measures. Discussion: Missed and kept-visit definitions of retention capture different constructs. Missed-visit measures are more strongly associated with poor HIV outcomes.