THE ASSOCIATION OF THE INSULIN-RESISTANCE-SYNDROME WITH IMPAIRED GLUCOSE-TOLERANCE AND NIDDM IN THE JAPANESE GENERAL-POPULATION - THE HISAYAMA STUDY

To elucidate the risk factors for initiating glucose intolerance, the relevant factors were explored in a cross-sectional survey conducted i n a sample population aged 40-79 years old selected from a Japanese co mmunity, Hisayama, Japan in 1988. A 75-g oral glucose tolerance test w as used to classify 1,073 men (72.5 % of the entire population in the same age range) and 1,407 women (80.5 %) into normal, impaired glucose tolerance and diabetes mellitus groups. In all age and sex groups wit h normal glucose tolerance, the sum of fasting and 2-h post-load insul in values varied widely and demonstrated significant positive correlat ions with triglycerides, body mass index, waist-hip ratio, systolic an d diastolic blood pressure, while it negatively correlated to HDL chol esterol (p < 0.05). Insulin resistance was presumed to develop in norm al glucose tolerance subjects with hyperinsulinaemia. The sum of the i nsulin concentrations, triglycerides, body mass index, waist-hip ratio and blood pressure levels was significantly associated with impaired glucose tolerance in all age and sex groups after adjustment for age ( p < 0.05) and was also related to diabetes in either all or some age a nd sex groups, respectively (p < 0.05). It was shown that glucose into lerance in the general population was associated with the factors rela ted to insulin resistance. These cross-sectional data, therefore, supp ort the hypothesis that insulin resistance is the primary defect in th e development of glucose intolerance in the Japanese general populatio n. However, a further prospective study is still needed in order to co nfirm this hypothesis.