Mortality and related risk factors in the co-presentation of tuberculosis and type 2 diabetes mellitus: a population-based study

Objective Patients with type 2 diabetes mellitus (T2DM) are often immunosuppressed and susceptible to infectious diseases. We investigated the mortality and related risk factors of active TB disease in patients with T2DM in Taiwan. Materials and Methods The data of 1258 patients diagnosed with both T2DM and active TB disease from January 1 to December 31, 2002 (T2DM-TB group) were retrieved from the Taiwan National Health Insurance Research Database. Patients in the T2DM-TB group were matched by age, sex, and comorbidities to a control group of 10,064 T2DM patients without TB disease (T2DM group). Patients were followed up since TB diagnosis until death or 31 December 2011. Cox proportional-hazards regression analysis was employed to compare the risk of death between the T2DM group and the T2DM-TB group. Results A total of 101,837 potentially eligible patients were included in the study. After 1:10 propensity score matching, 1,258 patients were classified in the T2DM-TB group and 10,064 patients in the T2DM group. After adjustment for age, sex and comorbidities, the T2DM-TB group showed a 2.16-fold higher mortality risk than the T2DM group (95% CI = 1.83-2.56, p < .001). The mortality risk remained higher after stratification by year. The log-rank test indicated that male sex, age >= 60 years, hypertension and heart failure were independent risk factors. Conclusions TB increases mortality risk in patients with T2DM on long-term follow-up. The independent risk factors for mortality in patients with concurrent T2DM and TB disease include male sex, age >= 60 years, hypertension and heart failure. KEY MESSAGES The co-presentation of T2DM and TB is an important emerging issue, especially in Asia. This study showed mortality risk was significantly higher in the T2DM-TB group compared with the T2DM group on long-term follow-up. Increased medical attention is necessary for patients with T2DM and a history of TB disease.