The American Diabetes Association and World Health Organization Classifications for Diabetes

Abstract

OBJECTIVE—To compare the prevalence of diabetes according to the American Diabetes Association (ADA) and World Health Organization (WHO) classifications in a sample of elderly Japanese-American men; to examine the association with total and cardiovascular mortality by diabetes status using both classifications; and to determine whether the fasting or 2-h glucose measurement is a stronger predictor of adverse outcomes. RESEARCH DESIGN AND METHODS—Examinations given from 1991 to 1993 in the Honolulu Heart Program were used as baseline for these analyses. Subjects were 71–93 years of age at that time and were followed for total and cardiovascular disease mortality for up to 7 years. RESULTS—A total of ∼66% of individuals who had diabetes by WHO criteria were missed when the ADA definition was used. The relative risks of total and cardiovascular mortality for those with versus those without diabetes were similar for both definitions; however, when fasting and postload glucose measures were analyzed as continuous variables, the 2-h measurement was a superior predictor and was independent of fasting glucose. In contrast, fasting glucose was not an independent predictor of these outcomes in the presence of the 2-h measurement. CONCLUSIONS—The prevalence of glucose metabolism abnormalities was very high among elderly Japanese-American men. The WHO classification was superior to the ADA classification in identification of subjects at high risk for adverse outcomes. Therefore, we conclude that the 2-h glucose measurement is valuable and should be retained in epidemiologic studies.