ABSTRACT
Objective: The increased risk of pulmonary tuberculosis [PTB] in patients with diabetes mellitus [DM] remains to be clarified with cohort study. The present study further examined whether the anti-diabetic drug treatment associates with developing PTB. Design: Nation wide cohort study Setting: China Medical University Hospital
Subjects: From the Taiwan National Health Insurance database, we identified 22,256 adult patients newly diagnosed with DM in 2000-2006 as DM cohort and 89,024 persons without DM frequency matched with sex, age and DM diagnosed year as non-DM comparison cohort. Intervention: None Main outcome measures: Both cohorts were followed till the end of 2009 to document PTB incidence. Medications were analyzed for the DM cohort to examine the hazard of developing PTB
Results: The incidence of PTB was 1.64-fold higher in DM cohort than in comparison cohort [52.1 Vs 31.8 per 10,000 person-years] with an adjusted hazard ratio of 1.53 [95% CI = 1.40 - 1.67], measured using multivariable Cox proportional hazards regression analysis. Men were at higher risk than women to have PTB. The age-specific incidence rates showed that DM cohort to comparison cohort incidence rate ratio was higher in younger group. However, the Cox model measured HR increased with age. Alcoholism, chronic obstructive pulmonary disease, alcoholic liver damage and chronic kidney diseases were comorbidities independently associated with PTB. In the DM cohort, anti-DM medications significantly reduced the risk of PTB with a HR of 0.52 for those who had taken metformin, followed by alpha-glucosidase inhibitors, thiazolidinediones, insulins and sulfonylureas [HR = 0.76]. The effects of all anti-diabetic drugs were statistically significant
Conclusions: These findings show patients with DM are associated with an elevated risk of developing PTB, but treatment with anti-diabetic drugs may mediate the risk significantly