Predictors of Treatment Outcome and Drug Resistance in Tuberculosis Patients at Yirgalem General Hospital, Sidama Region, South Ethiopia: A Retrospective Cohort Study

Abstract The spread of drug-resistant tuberculosis (DR-TB) poses a significant challenge to TB control efforts. This study assessed the prevalence of drug resistance and identified predictors among patients undergoing treatment for MDR-TB in south Ethiopia. A retrospective study spanning ten years, 2014–2023, was conducted, analyzing the records of confirmed cases of pulmonary DR-TB admitted to Yirgalem General Hospital. Out of 276 patients with confirmed multidrug-resistant (MDR-TB), 4(1.4%) cases were diagnosed with resistance to second-line drugs (SLDs) upon enrollment. The treatment success rate was 70.4%, with 53.6% cured and 16.8% completing the treatment which varied significantly (p-value?), ranging from 90% in 2021 to 4% in 2020. The proportion of deaths, lost-to-follow-up, and treatment failures were 11.2%, 15.3%, and 3.1%, respectively. Unsuccessful treatment outcomes were significantly associated with HIV positivity (adjusted odds ratio AOR: 3.200; 95% confidence interval (CI): 1.206, 8.493; p = 0.018), the presence of comorbid diseases other than HIV (AOR: 2.062; 95% CI: 0.875, 4.858; p = 0.040) and baseline body-mass-index of patients below 18kg/m 2 (AOR: 2.353; 95% CI: 1.404, 3.942; p = 0.001). The study revealed a concerning 1.4% prevalence of additional resistance to SLDs. The 29.6% rate of unsuccessful treatment among MDR-TB cases exceeds the target set by the WHO. A significant number of patients (15.3%) were LTFU. Enhanced strategic interventions are needed to reduce such cases, and factors associated with poor treatment outcomes should receive greater attention. Future prospective studies can further explore the factors influencing improved treatment success.