Epidemiological study of diabetes mellitus in the Hiroshima area-prevalence of diabetes mellitus and follow-up studies using the glucose tolerance test 5-19 years after initial testing.

Tests for diabetes mellitus have been performed annually since 1963 on about 100,000 A-bomb survivors living in Hiroshima. We report here on the trends over the 19 years leading up to 1981 for the glycosuria positive rate, the 75 g GTT results of positive cases and the findings of the 5-19 year follow-up. The glycosuria positive rate was 3-4 times higher in males. During the period of 1963-1979, the positive rate increased annually in both sexes, reaching 2.6 and 3.0 times the male-female values for 1963, but subsequently levelling off. When Body Mass Index (BMI) less than 25, 24.9% of the sample was diabetic (including those under treatment), 26.0% had Impaired Glucose Tolerance (IGT) and 49.1% were normal, whereas when BMI greater than or equal to 25, the rates were significantly higher being 45.0%, 27.4% and 27.6% respectively (p less than 0.001). Frequency increased with BMI, reaching 75.0% at BMI 33.3). Results of the 5-19 year follow-up showed the annual diabetes onset rate by the person year method in those with BMI less than 25 at initial GTT to be 1.72% among 848 normals, while it was a significantly higher 4.82% in those suffering from IGT. For those with BMI greater than or equal to 25, the rates were 3.77% among 161 normals and 7.93% among 132 IGT cases.