Predictors of loss to follow-up among patients receiving antiretroviral therapy in Njombe Region, Tanzania, 2017–2021

Abstract Background Loss to follow-up (LTFU) undermines the success of antiretroviral therapy (ART) programs, especially in high HIV prevalence regions like Njombe, Tanzania. Understanding factors influencing LTFU is critical to enhance patient retention. Aim To assess the prevalence and predictors of LTFU among people living with HIV (PLHIV) receiving ART in Njombe, Tanzania, from 2017 to 2021 Methods We conducted a retrospective cohort study using the National Care and Treatment Clinic (CTC2) database, defining LTFU as absence from care for 180 days or more. Logistic regression identified factors associated with LTFU. Data were cleaned using Microsoft Excel and analyzed using IBM SPSS Statistics version 26. Descriptive statistics were used to summarize demographic and clinical characteristics, and logistic regression was used to identify independent predictors of LTFU Results Of the 37,642 PLHIV initiated on ART, 13,411 (35.6%) were LTFU during the five-year study period. The highest annual incidence of LTFU occurred in 2020 (n = 4,069), coinciding with the onset of the COVID-19 pandemic. District-level disparities were substantial: Wanging’ombe recorded the highest disengagement prevalence (46.7%), while Makete recorded the lowest (23.7%). Multivariable analysis revealed that gender and age were not independent predictors of attrition (p > 0.05). However, significant associations with LTFU were observed for lower pharmacy refill adherence, marital status (single and divorced), and district of residence. Notably, patients in Wanging’ombe had more than double the odds of LTFU compared to those in Njombe (AOR 2.09; 95% CI: 1.95–2.24), whereas the 2021 initiation cohort demonstrated a significantly lower risk of disengagement (AOR 0.25; 95% CI: 0.22–0.28). Conclusion LTFU remains a critical challenge in the Njombe Region. Targeted interventions, including strengthened pharmacy refill monitoring, district-specific strategies, and psychosocial support for PLHIV, are essential to improve retention and sustain progress toward national HIV treatment goals.