Abnormal glucose tolerance and the risk of cancer death in the United States

Although abnormal glucose tolerance is a well-established risk factor for cardiovascular disease, its relation to cancer risk is less certain. Therefore, the authors performed a prospective cohort study using data from the Second National Health and Nutrition Examination Survey and the Second National Health and Nutrition Examination Survey Mortality Study to determine this relation. This analysis focused upon a nationally representative sample of 3,054 adults aged 30-74 years who underwent an oral glucose tolerance test at baseline (1976-1980). Deaths were identified by searching national mortality files through 1992. Adults were classified as having either previously diagnosed diabetes (n = 247), undiagnosed diabetes (n = 180), impaired glucose tolerance (n = 477), or normal glucose tolerance (n = 2250). There were 195 cancer deaths during 40,024 person-years of follow-up. Compared with those having normal glucose tolerance, adults with impaired glucose tolerance had the greatest adjusted relative hazard of cancer mortality (relative hazard = 1.87, 95% confidence interval (CI): 1.06, 3.31), followed by those with undiagnosed diabetes (relative hazard = 1.31, 95% CI: 0.48, 3.56) and diabetes (relative hazard = 1.13, 95% CI: 0.49, 2.62). These data suggest that, in the United States, impaired glucose tolerance is an independent predictor for cancer mortality.