The prevalence of diabetes mellitus among the patients with tuberculosis in Qom, Iran, during 2004-2016

Several studies have indicated the increasing risk of active tuberculosis (TB) due to diabetes mellitus (DM). The increasing prevalence of DM in areas with endemic TB may adversely influence spreading of TB. The current study is undertaken aiming to assess the prevalence of DM in patients with pulmonary TB.

This case control study was conducted on 522 participants during a period of 12 years from 2004-2016 in Qom city, central Iran. The control group was symptomatic respiratory patients without preceding history of active pulmonary TB in the same clinic (n = 261). The case and control groups were compared using the Chi-square test. In addition, adjusted odds ratios (OR) and 95% confidence interval for comparison of the DM prevalence among patients with TB across different groups were calculated by multivariate logistic regression.

Mean age of the case and control patients were 51.0 ± 20.5 and 54.0 ± 14.9 years, respectively and 40.4% of all participants were males. The prevalence of DM was higher in patients with TB compared to the control patients and the rate was found to be 26.5% with adjusted OR of 3.54. The DM prevalence was significantly associated with TB in patients with older age (P < 0.001).

The prevalence of DM is significantly higher among patients with TB compared to the general population. Moreover, the mean age of patients with TB with DM is significantly higher than expected in patients with TB without DM.