Rate and predictors of loss to follow-up in HIV care in a low-resource setting: analyzing critical risk periods

BACKGROUND: Patient loss-to-follow-up (LTFU) in HIV care is a major challenge, especially in low-resource settings. Although the literature has focused on the total rate at which patients disengage from care, it has not sufficiently examined the specific risk periods during which patients are most likely to disengage from care. By addressing this gap, researchers and healthcare providers can develop more targeted interventions to improve patient engagement in HIV care. METHODS: We conducted a retrospective cohort study on newly enrolled adult HIV patients at seven randomly selected high-volume health facilities in Ethiopia from May 2022 to April 2024. Data analysis was performed using SPSS version 26, with a focus on the incidence rate of LTFU during the critical risk periods. Cumulative hazard analysis was used to compare event distributions, whereas a Poisson regression model was used to identify factors predicting LTFU, with statistical significance set at p < 0.05. RESULTS: The analysis included 737 individuals newly enrolled in HIV care; 165 participants (22.4%, 95% CI: 19.5-25.2) were LTFU by the end of two years, of which 50.1% occurred within the first 6 months, 29.7% within 7-12 months, and 19.4% from 13 to 24 months on ART. The overall incidence rate of LTFU was 18.3 per 1,000 PMO (95% CI: 15.9-20.6), with rates of 167.7 in the first 6 months, 55.4 in 7-12 months, and 18.1 in 13-24 months. Incomplete addresses lacking a phone number or location information (IRR: 1.61; 95% CI: 1.14, 2.27) and poor adherence (IRR: 1.78; 95% CI: 1.28, 2.48) were factors predicting the incidence rate of LTFU. CONCLUSION: LTFU peaked in the first 6 months, accounting for approximately half of total losses, remained elevated from months 7-12, and stabilized after the first year of HIV care and treatment. Address information and adherence were predictors of LTFU. To effectively minimize LTFU, efforts should focus on intensive support during the first six months of care, followed by sustained efforts and monitoring in the next six months. Our findings highlight a critical period for targeted interventions to reduce LTFU in HIV care.