Assessing the Competing Risks of Loss to Follow-up and Mortality Among Adults Receiving Antiretroviral Therapy in Northern Ghana: Application of the Fine-Gray Subdistribution Hazard Model

Retention in antiretroviral therapy (ART) programmes remains a major public health challenge in HIV care, with loss to follow-up (LTFU) and death threatening treatment success. Because these outcomes are competing events, conventional survival methods may yield biased estimates of their incidence and associated risk factors. To estimate the cumulative incidence of LTFU and mortality and identify factors associated with these outcomes among adults receiving ART in Northern Ghana using a competing-risks framework. We conducted a retrospective cohort study of 329 adults living with HIV who initiated ART at Nalerigu Baptist Medical Centre, Ghana, between January 2013 and December 2019. Fine--Gray subdistribution hazard models were used to evaluate predictors of LTFU and death while accounting for competing risks. Cause-specific Cox proportional hazards models were fitted as a sensitivity analysis. The incidence rates were 2.2 per 100 person-months (95% CI: 1.9--2.6) for LTFU and 0.74 per 100 person-months (95% CI: 0.57--0.98) for death. At 36 months, the cumulative incidence was 50.2% for LTFU and 16.0% for death. Patients residing closer to the clinic had a lower cumulative incidence of LTFU than those living farther away (SHR = 0.68, 95% CI: 0.49--0.93), whereas higher baseline weight was associated with increased LTFU (SHR = 1.02 per kg, 95% CI: 1.00--1.04). Mortality was lower among patients receiving efavirenz-based regimens (SHR = 0.27, 95% CI: 0.15--0.50), females (SHR = 0.39, 95% CI: 0.18--0.85), and those with higher baseline weight (SHR = 0.93 per kg, 95% CI: 0.90--0.96). Findings were broadly consistent in cause-specific Cox models. LTFU was substantially more frequent than mortality among adults receiving ART in Northern Ghana. Travel distance to the treatment facility was an important barrier to retention, while ART regimen, sex, and baseline weight were associated with mortality. Expanding access to ART services through decentralized and community-based models may improve retention and support efforts to achieve HIV control targets.