Factors associated with deaths among pulmonary tuberculosis patients: a case-control study with secondary data

Background: Tuberculosis remains an important public health problem in Brazil where over 100 000 new cases and 6000 deaths are reported every year. Current drug efficacy and wide availability should have curbed this toll. The goal was to study the factors associated with death in incident cases of pulmonary tuberculosis (PT) during treatment. Methods: This is a case-control study including all new cases of PT reported between 2000 and 2004; cases were patients who died of any cause and controls were those cured after initial PT treatment. Data analyses included unconditional multiple hierarchical logistic regression. Results: A total of 313 502 new cases of tuberculosis were reported between 2000 and 2004; 224 355 (71.6%) were cured after initial treatment and 20 721 (6.6%) died during the surveillance follow-up. Over 82% of all cases were diagnosed with PT. After controlling for significant variables, the factors associated with a higher risk of death included gender (males: odds ratio (OR) 1.4; 95% confidence interval (CI) 1.33 to 1.47), age (, 5 years of age: OR 1.90; 95% CI 1.51 to 2.38; 30-59 years: OR 2.78; 95% CI 2.61 to 2.97; over 60 years: OR 10.92; 95% CI 10.09 to 11.81), positive HIV serology (OR 10.59; 95% CI 9.76 to 11.48), alcoholism (OR 1.49; 95% CI 1.36 to 1.65), mental disorder (OR 1.80; 95% CI 1.43 to 2.27) and presence of additional lung pathology on chest x ray (OR 2.22; 95% CI 1.83 to 2.70). Protective variables included education (highest level: OR 0.67; 95% CI 0.63 to 0.70). Conclusions: Preventive interventions should target the most vulnerable patients, in particular the very young and the elderly, those infected with HIV and those presenting with a mental disorder or additional lung pathology.