ABSTRACT
We have carried out the mass survey for diabetes mellitus by a 50 g GTT as the first screening since 1971. Average incidences of diabetic pattern, IGT pattern, borderline pattern and normal pattern in a Glucose Tolerance Test (GTT) were 2.3±1.8%, 6.6±1.7%, 19.8±6.6% and 71.4 ±7.8%, respectively. 21 males and 6 females were found to be diabetic by this survey for 11 years. Insulinogenic indices (I. Is.) of diabetic, IGT, borderline and normal patterns were 0.13±0.07, 0.70±0.37, 0.58±0.40 and 1.05±0.30, respectively, and the values of I. I. in diabetics and borderline diabetics were significantly lower than that in the normal pattern. A I. I. in the subjects who have revealed the normal glucose tolerance every year for 11 year, 2.62±1.28, was high in the normal range. On the other hand, a I. I. in the subjects who became overtly diabetic from the IGT, borderline or normal pattern, 0.36±0.31, was significantly lower. Therefore, taking into consideration that one of the characteristics of NIDDM is low insulin response to glucose, the mass survey for diabetes mellitus should be carried out by a Glucose Tolerance Test (GTT) as the first screening with the measurement of plasma insulin concentrations. A follow-up study for the low insulin responder is considered to be one of the most preferable investigations for the detection of the early stage of diabetes mellitus.