Prevalence and incidence of diabetes mellitus by WHO criteria.

The recent data on the prevalence and incidence of diabetes mellitus in Japan are presented. The data were obtained in 1989-1992 based on the 1985 WHO criteria. The prevalence and incidence for childhood IDDM (0-18 years) were chiefly derived from the records of patients who received free medical care for diabetes. The prevalence was 10-15 per 100,000 and incidence was 1.2-2.0 per 100,000 in most regions of Japan. There is no increasing tendency from south to north. The prevalence of diabetes (mostly NIDDM) in the population aged 40 years or older studied using the 75 g oral glucose tolerance test ranged from 4 to 12%. Men were affected more frequently than women in most areas. There are problems with the data on the incidence of NIDDM obtained so far. The nation-wide survey of HbA1c suggests about a 2-fold difference in abnormally high HbA1c in different regions of Japan.