Diabetes mellitus and extrapulmonary tuberculosis: site distribution and risk of mortality

Scarce data exist on the relationship between diabetes and extrapulmonary tuberculosis (EPTB). We evaluated whether diabetes impacts site of TB and risk of death in patients with EPTB. We evaluated a cohort of TB cases from the state of Georgia between 2009 and 2012. Patients aged ⩾16 years were classified by diabetes status according to medical records. Site of EPTB was determined by culture and/or state TB classification. Death was defined by all-cause mortality. Of 1325 eligible reported TB cases, 369 (27·8%) had any EPTB including 258 (19·5%) with only EPTB and 111 (8·4%) with pulmonary TB and EPTB. Of all TB cases, 158 had diabetes (11·9%). In multivariable analysis, the odds of any EPTB was similar in patients with and without diabetes [adjusted odds ratio 1·04, 95% confidence interval (CI) 0·70-1·56]. The risk of death was 23·8% in patients with EPTB and diabetes vs. 9·8% in those with no diabetes (P < 0·01); after adjusting for covariates the difference was not significant (aRR 1·19, 95% CI 0·54-2·63). Diabetes was common in patients with EPTB and risk of death was high. Improved understanding of the relationship between diabetes and EPTB is critical to determine the extent that diabetes affects TB diagnosis and clinical management.