[Epidemiology of connective tissue diseases of the skin (scleroderma, dermatomyositis and polymyositis) in Japan].

An epidemiologic study of connective tissue diseases (scleroderma, dermatomyositis, and polymyositis) performed from 1973 to 1976 in Japanese university hospitals is reported. Data from 32 of 48 university hospitals revealed that a total of 659 cases were collected. There were 396 cases of progressive systemic sclerosis, 178 cases of dermatomyositis, and 85 cases of polymyositis. The following points were analyzed: relationship of regional incidence, sex, initial symptoms, laboratory findings, and statistical analysis of autopsies.