Diabetes Mellitus as a Risk Factor for Tuberculosis: A Community Based Case Control Study

Prevention of diabetes in the general population can help reduce the incidence of tuberculosis. Hence it is necessary to document that diabetes is strongly associated with tuberculosis as a risk factor. To study if diabetes is associated with tuberculosis compared to controls. A community based case-control study was carried out. 215 newly diagnosed cases of tuberculosis on treatment for not more than three months were selected randomly from the randomly selected tuberculosis unit. 215 neighbourhood controls were selected. They were matched for the age group of ± 10 years and sex. Fasting blood sugar (FBS) was estimated using a glucometer. Tobacco chewing, residence and family history of TB were significantly more in cases (P < 0.05). Mean BMI was significantly lower in cases compared to controls. The proportion of TB cases among the known cases of diabetes was 67% compared to 33% in controls, which was statistically significant. Mean FBS was significantly higher in cases compared to controls (P < 0.05). The odds of cases being diabetic was 2.456 times more than those of controls. On binary logistic regression, diabetes was an independent risk factor for tuberculosis. Other independent risk factors were tobacco chewing, and family history of TB. Family history of tuberculosis, and tobacco chewing were positively associated with tuberculosis whereas body mass index was negatively associated with tuberculosis. Diabetes was significantly associated with tuberculosis.