The Impact of Churn on HIV Outcomes in a Southern United States Clinical Cohort

Background. Persons with human immunodeficiency virus (PWH) may experience a cycle of engaging and disengaging in care referred to as "churn." While human immunodeficiency virus (HIV) churn is predicted to be more prevalent in the southern United States (US), it has not been well characterized in this region. Methods. We conducted a retrospective cohort study involving PWH newly establishing care at a large urban clinic in Atlanta, Georgia, from 2012 to 2017, with follow-up data collected through 2019. The primary exposure was churn, defined as a >= 12-month gap between routine clinic visits or viral load (VL) measurements. We compared HIV metrics before and after churn and assessed the risk of future churn or loss to follow-up. Results. Of 1303 PWH newly establishing care, 81.7% were male and 84.9% were Black; 200 (15.3%) experienced churn in 3.3 years of median follow-up time. The transmissible viremia (TV) rate increased from 28.6% prechurn to 66.2% postchurn (P < .0001). The 122 PWH having TV on reengagement had delayed time to subsequent viral suppression (adjusted hazard ratio, 0.59 [95% confidence interval {CI},.48-.73]), and PWH returning to care contributed disproportionately to the community viral load (CVL) (proportion of CVL/proportion of patients, 1.96). Churn was not associated with an increased risk of subsequent churn (adjusted odds ratio [aOR], 1.53 [95% CI,.79-2.97]) or loss to follow-up (aOR, 1.04 [95% CI,.60-1.79]). Conclusions. The rate of churn in a southern US clinic was high, and those who experienced churn had increased TV at reentry and disproportionately contributed to the CVL and likely contributing to ongoing HIV transmission.