American Journal of Epidemiology Advance Access originally published online on April 8, 2008
American Journal of Epidemiology 2008 167(12):1486-1494; doi:10.1093/aje/kwn075
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ORIGINAL CONTRIBUTIONS |
Diabetic Control and Risk of Tuberculosis: A Cohort Study
1 Tuberculosis and Chest Service, Department of Health, Hong Kong, People's Republic of China
2 Department of Community Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
3 Elderly Health Service, Department of Health, Hong Kong, People's Republic of China
4 Tuberculosis and Chest Unit, Grantham Hospital, Hong Kong, People's Republic of China
Correspondence to Dr. Chi Chiu Leung, Wanchai Chest Clinic, 99 Kennedy Road, Wanchai, Hong Kong, People's Republic of China (e-mail: cc_leung{at}dh.gov.hk).
Received for publication September 6, 2007. Accepted for publication March 6, 2008.
Diabetes mellitus is associated with tuberculosis. A cohort of 42,116 clients aged 65 years or more, enrolled at 18 Elderly Health Service centers in Hong Kong in 2000, were followed up prospectively through the territory-wide tuberculosis registry for development of tuberculosis from 3 months after enrollment to December 31, 2005, by use of their identity card numbers as unique identifier. The effects of diabetes mellitus and diabetic control on tuberculosis risk were assessed with adjustment for sociodemographic and other background variables. Diabetes mellitus was associated with a modest increase in the risk of active, culture-confirmed, and pulmonary (with or without extrapulmonary involvement) but not extrapulmonary (with or without pulmonary involvement) tuberculosis, with adjusted hazard ratios of 1.77 (95% confidence interval: 1.41, 2.24), 1.91 (95% confidence interval: 1.45, 2.52), 1.89 (95% confidence interval: 1.48, 2.42), and 1.00 (95% confidence interval: 0.54, 1.86), respectively. Diabetic subjects with hemoglobin A1c <7% at enrollment were not at increased risk. Among diabetic subjects, higher risks of active, culture-confirmed, and pulmonary but not extrapulmonary tuberculosis were observed with baseline hemoglobin A1c
7% (vs. <7%), with adjusted hazard ratios of 3.11 (95% confidence interval: 1.63, 5.92), 3.08 (95% confidence interval: 1.44, 6.57), 3.63 (95% confidence interval: 1.79, 7.33), and 0.77 (95% confidence interval: 0.18, 3.35), respectively.
aged; diabetes mellitus; tuberculosis