Tuberculosis-associated mortality and its risk factors in a district of Shanghai, China: a retrospective cohort study

Abstract

Setting: Pulmonary tuberculosis (PTB) causes a considerable number of deaths in China; however, the factors related to mortality are not well known.

Objective: To determine mortality among PTB patients and to explore its risk factors in Shanghai, China.

Design: This was a retrospective population-based study. A cohort of PTB patients who initiated treatment in a district of Shanghai from 2004 to 2015 was evaluated. Mortality in PTB patients was studied using the standardised mortality ratio (SMR) and Cox's proportional hazards model.

Results: Of 2741 PTB patients recruited in our study, 394 (14.4%) died during the 12-year follow-up. The summarised SMR was 2.8, and death was most likely to occur during the first months of anti-tuberculosis treatment. Age 60 years (adjusted hazard ratio [aHR] 4.039, P < 0.001), male sex (aHR 1.603, P < 0.001), sputum smear test positivity (aHR 1.945, P < 0.001), multidrug-resistant TB (MDR-TB; aHR 3.502, P = 0.001), diabetes mellitus (aHR 1.422, P = 0.012), chronic obstructive pulmonary disease (aHR 2.505, P < 0.001) and having cancer (aHR 4.319, P < 0.001) were risk factors for PTB mortality.

Conclusion: The overall mortality in PTB patients was higher than that in the general population. MDR-TB and comorbidity were the two leading risk factors for mortality in PTB patients. Early, accurate diagnosis, together with comprehensive management and treatment, can reduce the mortality rate in PTB patients.