Tobacco consumption is a reversible risk factor associated with reduced successful treatment outcomes of anti-tuberculosis therapy

Objective: The aim of this study was to evaluate the reversible factors that could possibly affect outcomes of anti-tuberculosis (anti-TB) treatment. Methods: A retrospective observational nested case-control study was performed to evaluate the association of patient and clinical factors with anti-TB therapy outcomes as defined by the World Health Organization (WHO). Results: To examine the impact of a variety of factors on the outcomes of anti-TB treatment, a total of 302 TB patients were included in the study. Univariate analysis revealed that age, gender, concurrent hypertension, asthma/chronic obstructive pulmonary disease, or liver disease, worsened baseline blood urea nitrogen or creatinine, ethambutol <800 mg/day, hepatitis or adverse skin reactions during therapy, smoking history, and current tobacco consumption were significant factors in decreasing both the cure rate and treatment completion rate. However, multivariate regression showed that only age, current daily tobacco consumption, baseline liver disease, and ethambutol dosage were independent factors. A high level of tobacco consumption (>20 cigarettes per day) was significantly associated with a decreased odds of cure or treatment completion (odds ratio 0.23, 95% confidence interval 0.05-0.98, p = 0.047). Conclusions: As smoking significantly inhibits the effectiveness of TB treatment, the integration of smoking cessation into TB treatment programs is strongly advocated to reduce the dual global burden of smoking and TB. Crown Copyright (C) 2011 Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. All rights reserved.