Treatment outcomes for drug-resistant tuberculosis: a retrospective longitudinal study

Background This study examined the treatment outcomes of multidrug-resistant tuberculosis (MDR-TB) in Kazakhstan, where its burden is notably high. Methods The authors conducted a retrospective longitudinal study using the National Tuberculosis Registry, this study analyzed treatment outcomes in MDR-TB patients from 2018 to 2021, and included adult patients (≥ 18 years) who completed a specific treatment. Outcomes were categorized into successful and unsuccessful treatments. Bivariate and multivariate Poisson regression models with modified errors were employed to obtain crude and adjusted risk ratios (aRR). Results The study cohort comprised 12,698 cases, of which 10, 306 (81.16%) completed treatment with a successful outcome, while 2,392 (18.84%) had unsuccessful outcomes. Male sex (aRR 1.35, 95% CI 1.24-1.45), urban residency (aRR 1.16, 95% 1.07-1.24), having both extrapulmonary and pulmonary tuberculosis (aRR 1.49, 95% 1.04-2.15), XDR-TB (aRR 1.31, 95% 1.08-1.59), excessive alcohol consumption (aRR 1.43, 95% 1.28-1.59), HIV-positive status (aRR 2.24, 95% 2.01-2.47), and drug abuse (aRR 1.37, 95% 1.10-1.71) significantly elevated the risk of the unsuccessful treatment. Conclusion Our findings underscore the need for focused strategies to reduce the MDR-TB burden, particularly among adults, male sex, relapsed cases, and XDR-TB. Despite the encouraging findings observed, further studies are necessary to update our estimates.