THE ASSOCIATION OF PERIODIC PARALYSIS AND HYPERTHYROIDISM IN JAPAN

ALTHOUGH periodic paralysis is a rare disorder, its association with hyperthyroidism has been reported by several investigators (1–15). In reviewing the literature, it was found that only about 30 such cases have been reported from the United States and Europe, whereas more than 70 cases have been reported from Japan. Possibly the association of these two disorders is less rare in Japan. As the Japanese reports were all concerned with relatively small numbers of patients with hyperthyroidism, the incidence of the association of these two disorders in Japan could not be estimated. In order to obtain a fairly good estimate, the incidence of periodic paralysis among 6,333 cases of hyperthyroidism operated upon in three thyroid hospitals in Japan was studied. These hospitals were located in different parts of country—Noguchi Hospital in Beppu, Kyushu (southern part of Japan), Kuma Hospital in Kobe (central part of Japan) and Ito Hospital in Tokyo (eastern part of Japan), so the study provided data on a cross section of Japanese patient populations.