Impact of HIV-AIDS on tuberculosis treatment outcome in Southern Ethiopia – A retrospective cohort study

Background: Globally, the Tuberculosis treatment success rate was worse for HIV-positive TB patients compared with HIV- negative TB patients. This study aimed at determining the impact of HIV-AIDS and factors associated with TB treatment outcomes. Methods: This study was a retrospective cohort study of five years of tuberculosis data from four public health facilities in Hosanna Town. A total of 604 study participants were included using a systematic random sampling technique. Descriptive analysis of ratios, rates, and proportions was done and binary logistic regression, bivariable and multivariable, analysis was also done. Result: A total of 604 TB patients were enrolled in this study. 302 (50%) were HIV co-infected. The overall treatment success rate was 90.1% (544/604). Treatment success rates are 86.4% (261/302) for TB-HIV co-infected patients and 93.7% (283/302) for non-co-infected patients. TB-HIV co-infected patients had a higher risk of an unsuccessful treatment outcome (Adjusted Relative Risk [ARR]: 2.7; 95% Confidence Interval [CI]: 1.4 - 5.2). The risk of unsuccessful treatment outcome is also higher among rural residents (ARR: 3.3; CI: 1.4 - 5.0), patients on the re-treatment category (ARR: 2.7; CI: 1.4 - 5.1), and with chronic disease (ARR: 3.3; CI: 1.3 - 8.1). Conclusion: TB treatment success rate is good as compared to the WHO minimum requirement. Successful treatment outcome is lower among patients with HIV infection, rural residents, patients on re-treatment, and patients with chronic disease. Therefore, due emphasis should be given to these high-risk groups.