Cotrimoxazole prophylaxis, poor drug adherence, nutritional and educational status are key predictors of first-line antiretroviral therapy (ART) treatment failure among adults in Southern Ethiopia

Background: The advent of antiretroviral therapy (ART) for HIV-infected patients has led to a significant decline in HIV-related morbidity and mortality conditions, globally. However, drug resistance with subsequent treatment failure becomes a great challenge. Objective: This study aimed to determine the incidence and key factors associated with treatment failure of first-line ART therapy among adults living with HIV in Gedeo Zone of the southern Ethiopia region. Methods: A facility-based retrospective follow-up study involving 509 patients who were 15 years and above old who started first-line ART between 2010 and 2017 was conducted at health facilities in Gedeo zone of southern Ethiopia. Data were collected from Dilla university referral hospital and Yirgachefe hospitals between March to April 2018. Systematic random sampling was used to select the study participants. Data were collected by five trained nurses. Survival analysis with a Cox proportional hazard model was fitted to determine factors associated with ART treatment failure. Variables with a p-value of ≤ 0.05 in multivariable cox regression were considered statistically significant determinant factors. Result: For a total of 3157 person-years follow-up or 509 adult HIV-infected patients on first-line ART at both hospitals, the cumulative treatment failure rate was found to be three per 100 person-years or nearly one in five 94 (18.5%). Using the cox hazard analysis at multivariate level, cotrimoxazole prophylaxis (AHR 2.96; 95% CI 1.35 to 6.47), poor adherence to ART (AHR 1.31; 95% CI 1.12 to 1.72), being malnourished (AHR 1.78; 95% CI 1.03 to 3.12), and lack of formal education (AHR 2.25; 95% CI 1.24 to 4.08) were independent predictors of treatment failure. Conclusion: The cumulative rate of treatment failure in the study area is high. Poor treatment adherence, cotrimoxazole prophylaxis, and educational and nutritional status were found to be key predictors of treatment failure. Therefore, health system strengthening and nutrition interventions are essential to improve the rate of treatment failure. Keywords: Adults, First-line Antiretroviral Therapy, HIV, Predictors, Treatment Failure