Directly Observed Therapy Reduces Tuberculosis-Specific Mortality: A Population-Based Follow-Up Study in Taipei,Taiwan

Objectives

To determine the effect of directly observed therapy (DOT) on tuberculosis-specific mortality and non-TB-specific mortality and identify prognostic factors associated with mortality among adults with culture-positive pulmonary TB (PTB).

Methods

All adult Taiwanese with PTB in Taipei, Taiwan were included in a retrospective cohort study in 2006–2010. Backward stepwise multinomial logistic regression was used to identify risk factors associated with each mortality outcome.

Results

Mean age of the 3,487 patients was 64.2 years and 70.4% were male. Among 2471 patients on DOT, 4.2% (105) died of TB-specific causes and 15.4% (381) died of non-TB-specific causes. Among 1016 patients on SAT, 4.4% (45) died of TB-specific causes and 11.8% (120) died of non-TB-specific causes. , After adjustment for potential confounders, the odds ratio for TB-specific mortality was 0.45 (95% CI: 0.30–0.69) among patients treated with DOT as compared with those on self-administered treatment. Independent predictors of TB-specific and non-TB-specific mortality included older age (ie, 65–79 and ≥80 years vs. 18–49 years), being unemployed, a positive sputum smear for acid-fast bacilli, and TB notification from a general ward or intensive care unit (reference: outpatient services). Male sex, end-stage renal disease requiring dialysis, malignancy, and pleural effusion on chest radiography were associated with increased risk of non-TB-specific mortality, while presence of lung cavities on chest radiography was associated with lower risk.

Conclusions

DOT reduced TB-specific mortality by 55% among patients with PTB, after controlling for confounders. DOT should be given to all TB patients to further reduce TB-specific mortality.