Incidence of pulmonary tuberculosis among diabetics.

SETTING

Longitudinal epidemiological study based on diabetic and non-diabetic civil servants in Korea.

OBJECTIVE

To determine a comparative incidence of pulmonary tuberculosis (PTB) between diabetic and non-diabetic subjects.

DESIGN

Investigation of newly developed PTB among diabetics and non-diabetics between 1988 and 1990, on the basis of biennial medical examination and the medical records of those who claimed health insurance for tuberculosis.

RESULTS

The 1990 medical examination and investigation of medical records of the health insurance claimants revealed that PTB had developed in 170 patients (including 37 smear and eight culture positives) among 8015 diabetics, and in 4935 patients (including 538 smear and 342 culture positives) among 806,698 control subjects. Estimated annual incidence rates of PTB of (1) all types, (2) smear and/or culture positive versus (3) smear positive cases were 1061, 281 and 231 per 10(5) respectively among diabetics and 306, 55 and 33 per 10(5) among non-diabetic controls. PTB developed in 167 of 7695 male diabetics and in 3 of 320 female diabetics. The greater the age, the more diabetics were found.

CONCLUSION

Relative risks (RR) of developing PTB of all types and bacteriologically confirmed cases were 3.47 times and 5.15 times higher in the diabetics than in the matched controls. A greater RR was observed on those at the age of 30-49 than in those of 50 years or more.