Subclinical stales of glucose intolerance and risk of death in the US

OBJECTIVE - Although clinically evident type 2 diabetes is a it ell-establi shed cause of mortality, less is known about subclinical states of glucose intolerance. RESEARCH DESIGN AND METHODS - Data from the Second National Health and Nutrition Exa mination Survey Mortality Study, a prospective study of adults, were analyz ed. This analysis focused on a nationally representative sample of 3,174 ad ults aged 30-75 years who underwent an oral glucose tolerance rest at basel ine (1976-1980) and who were followed up for death through 1992. RESULTS - Using 1985 World Health Organization criteria, adults were classi fied as having previously diagnosed diabetes (n = 248), undiagnosed diabete s (n = 183), impaired glucose tolerance (IGT) (n = 480), or normal glucose tolerance (n = 2,263). For these groups, cumulative all-cause mortality thr ough age 70 was 41, 34, 27, and 20%, respectively (P < 0.001). Compared wit h those with normal glucose tolerance, the multivariate adjusted RR of all- cause mortality was greatest for adults with diagnosed diabetes (RR2.11, 95 % CI 1.56-2.84), followed by those with undiagnosed diabetes (1.77, 1.13-2. 75) and those with IGT(1.42, 1.08-1.87; P < 0.001). A similar pattern of ri sk was observed For cardiovascular disease mortality. CONCLUSIONS - In the U.S., there was a gradient of mortality associated wit h abnormal glucose tolerance ranging from a 40% greater risk in adults with IGT to a 110% greater risk in adults with clinically evident diabetes. The se associations were independent of established cardiovascular disease risk factors.