A retrospective cohort analysis of treatment outcomes of patients with tuberculosis who used substances in Tel Aviv, Israel

Aims: To outline the demographic, clinical, laboratory characteristics, and treatment outcomes of tuberculosis (TB) patients who used substances. Methods: This retrospective cohort study compared 50 TB patients who used substances with a matched random sample of 100 TB patients who did not use substances between 2007 and 2017. Treatment failure was defined as a sputum smear or culture that tested positive after 5 months of treatment, loss to follow-up, unevaluated patients, or death. Results: TB patients who used substances were typically younger, experienced homelessness, smokers, and had fewer chronic diseases than those who did not use substances. They also were hospitalized for longer periods, their treatment durations were longer, had higher rates of multidrug resistant strains, increased rates of treatment failure, and higher mortality. Individuals whose treatment failed predominantly originated from the former Soviet Union, experienced homelessness, and had chronic diseases compared with those whose treatment was successful. In the multivariate analysis, homelessness [odds ratios (OR) = 6.7], chronic diseases (OR = 12.4), and substance use (OR = 4.0) were predictors of treatment failures. Conclusions: TB patients who used substances were more likely to have treatment failure. Targeted interventions, including early diagnosis and enhanced support during treatment, are essential to achieve treatment success in this vulnerable population, in addition to TB-alcohol/drug collaborative activities.