Directly observed therapy of tuberculosis in Brazil: associated determinants and impact on treatment outcome

SETTING: All Brazilian states. OBJECTIVES: To assess the determinants of tuberculosis (TB) in patients undergoing directly observed therapy (DOT) and the impact of DOT on treatment outcomes. DESIGN: This is a cross-sectional study among TB patients aged 18 years conducted in 2011. The primary outcome was the status of DOT received, while the secondary was the outcome of anti-tuberculosis treatment. RESULTS: In 2011, 35 775 (38.3%) subjects received DOT. The odds of receiving DOT were higher in patients with the following characteristics: brown/mestizo patients (OR 1.18, 95%CI 1.14-1.22) and those of other ethnic groups (OR 2.01, 95%CI 1.79-2.27) compared to Whites, alcohol users (OR 1.37, 95%CI 1.28-1.47) and those with mental disorders (OR 1.88, 95%CI 1.54-2.29). The odds of receiving DOT were lower in human immunodeficiency virus positive patients (OR 0.64, 95%CI 0.60-0.68). Patients who did not receive DOT were more likely to default from anti-tuberculosis treatment (OR 0.62, 95%CI 0.57-0.66), die due to TB (OR 0.68, 95%CI 0.61-0.77) and to have unknown treatment outcomes (OR 0.71, 95%CI 0.66-0.76). The adjusted preventable fraction of DOT in the reduction of unfavorable outcomes was 25%. CONCLUSION: Sociodemographic and clinical characteristics are determinants of anti-tuberculosis treatment outcomes in patients undergoing DOT; DOT use led to a 25% reduction in unfavorable outcomes.