[Epidemiology of Basedow disease and other thyroid diseases]

Basedow disease is one of several representative thyroid diseases. According to information from Japan's Ministry of Health, Labour and Welfare, it is estimated that there were a total of about 130,000 patients (32,000 male 98,000 female, sex ratio of 1 : 3) of thyrotoxicosis in Japan during 2002. This number accounts for about 0.1% of the entire population of Japan. Several reports based on data from medical examinations provide higher prevalence rates. A survey of subclinical thyroid diseases is now in progress. There are reports of cases of progression from subclinical status to overt status, which suggests that the number of affected individuals becomes higher. Epidemiological data are still insufficient. Disease registry systems and medical examination data should be further improved.