The role of diabetes mellitus in the higher prevalence of tuberculosis among Hispanics

Objectives. This research studied the relative contribution of diabetes mellitus to the increased prevalence of tuberculosis in Hispanics. Methods. A case-control study was conducted involving all 5290 discharges from civilian hospitals in California during 1991 who had a diagnosis of tuberculosis, and 37 366 control subjects who had a primary discharge diagnosis of deep venous thrombosis, pulmonary embolism, or acute appendicitis. Risk of tuberculosis was estimated as the odds ratio (OR) across race/ethnicity, with adjustment for other factors. Results. Diabetes mellitus was found to be an independent risk factor for tuberculosis. The association of diabetes and tuberculosis was higher among Hispanics (adjusted OR [OR(adj)] = 2.95; 95% confidence interval [CI] = 2.61, 3.33) than among non-Hispanic Whites (OR(adj) = 1.31; 95% CI = 1.19, 1.45); among non-Hispanic Blacks, diabetes was not found to be associated with tuberculosis (OR(adj) = 0.93; 95% CI = 0.78, 1.09). Among Hispanics aged 25 to 54, the estimated risk of tuberculosis attributable to diabetes (25.2%) was equivalent to that attributable to HIV infection (25.5%). Conclusions. Diabetes mellitus remains a significant risk factor for tuberculosis in the United States. The association is especially notable in middle-aged Hispanics.