GLUCOSE-INTOLERANCE AND ADENOMAS OF THE SIGMOID COLON IN JAPANESE MEN(JAPAN)

Objectives: The purpose was to investigate the relation between glucos e tolerance and risk of sigmoid colon adenomas, a well-established pre cancerous lesion, in Japanese men. Methods: In the consecutive series of 7,637 men aged 48 to 59 years who received a preretirement health e xamination at four hospitals of the Self Defense Forces (SDF) in Japan from 1986 to 1994, we identified 821 cases of sigmoid colon adenomas and 4,372 controls with normal sigmoidoscopy or colonoscopy at 60 cm o r more from the anus. Glucose tolerance status was classified as norma l, impaired glucose tolerance (IGT), newly diagnosed non-insulin depen dent diabetes mellitus (NIDDM), or diabetes mellitus under treatment, based on a 75g oral glucose tolerance test and medical history. Statis tical adjustment was made for body mass index (wt/ht(2)), cigarette sm oking, alcohol use, rank of the SDF, and hospital. Results: Modest inc reases in adenoma risk were observed for newly diagnosed NIDDM and dia betes mellitus under treatment while there was no association between IGT and adenoma risk. When small (< 5 mm in diameter) and large (5+ mm ) adenomas were analyzed separately, increased risk associated with ne wly diagnosed NIDDM was more pronounced for small adenomas, and diabet es mellitus under treatment showed a slightly stronger association wit h large adenomas. Conclusions: The findings suggest that NIDDM is asso ciated with modestly increased risk of sigmoid colon adenomas, and add to evidence that hyperinsulinemia increases colon cancer risk.