Addison's disease in Japan: characteristics and changes revealed in a nationwide survey.

Patients with Addison's disease, newly diagnosed in the last five years were surveyed nationwide in conjunction with two past surveys. The decreasing incidence, i.e., 168 patients from 1977 to 1981 (survey 1), 108 from 1982 to 1986 (survey 2), and 74 from 1987 to 1991 (the present survey), reflects a decrease in the incidence (n = 28) of tuberculous Addison's disease, but not that (n = 36) of idiopathic Addison's, making the idiopathic form predominant for the first time in the history of the disease in Japan. Because the interval between the preceding tuberculosis and the onset of Addison's averages 32 +/- 15 years, tuberculous Addison's has a relatively late onset. Pigmentation is the most frequent symptom (90%). Other symptoms, abnormal laboratory data, and positive adrenal antibodies are observed less frequently in Japan than in North America or Europe. The types of associated disorders are also distributed differently. Adrenal CT and MRI scans have been the most useful means in differentiating between the two major types of the disease. This report focuses on features distinguishing Japanese sufferers from their western counterparts.