Initial Presentations Predict Mortality in Pulmonary Tuberculosis Patients - A Prospective Observational Study

BACKGROUND Despite effective anti-TB treatments, tuberculosis remains a serious threat to public health and is associated with high mortality. Old age and multiple co-morbidities are known risk factors for death. The association of clinical presentations with mortality in pulmonary tuberculosis patients remains an issue of controversy. METHODS This prospective observational study enrolled newly diagnosed, culture-proven pulmonary tuberculosis patients from five medical centers and one regional hospital, which were referral hospitals of TB patients. Radiographic findings and clinical symptoms were determined at the time of diagnosis. Patients who died for any reason during the course of anti-TB treatment were defined as mortality cases and death that occurred within 30 days of initiating treatment was defined as early mortality. Clinical factors associated with overall mortality and early mortality were investigated. RESULTS A total of 992 patients were enrolled and 195 (19.7%) died. Nearly one-third (62/195, 31.8%) of the deaths occurred before or within 30 days of treatment initiation. Older age (RR = 1.04, 95%CI: 1.03-1.05), malignancy (RR = 2.42, 95%CI: 1.77-3.31), renal insufficiency (RR = 1.77, 95%CI: 1.12-2.80), presence of chronic cough (RR = 0.63, 95%CI: 0.47-0.84), fever (RR = 1.45, 95%CI: 1.09-1.94), and anorexia (RR = 1.49, 95%CI: 1.07-2.06) were independently associated with overall mortality. Kaplan-Meier survival analysis demonstrated significantly higher mortality in patients present with fever (p<0.001), anorexia (p = 0.005), and without chronic cough (p<0.001). Among patients of mortality, those with respiratory symptoms of chronic cough (RR = 0.56, 95%CI: 0.33-0.98) and dyspnea (HR = 0.51, 95%CI: 0.27-0.98) were less likely to experience early mortality. The radiological features were comparable between survivors and non-survivors. CONCLUSIONS In addition to demographic characteristics, clinical presentations including the presence of fever, anorexia, and the absence of chronic cough, were also independent predictors for on-treatment mortality in pulmonary tuberculosis patients.