Clinical and epidemiologic analysis of giant cell (temporal) arteritis from a nationwide survey in 1998 in Japan: The first government-supported nationwide survey

Objective. To elucidate epidemiologic and clinical manifestations of Japanese patients with giant cell arteritis (GCA), the first nationwide survey for GCA was conducted in 1998 in Japan. Methods. The first questionnaire on GCA for patients treated in 1997 was sent to 10,717 medical departments in Japan. A total of 177 patients were reported. Among the 177 patients, 66 GCA patients with detailed clinical and epidemiologic features on second survey were analyzed. Results. Prevalence in patients 50 years of age and older in 1997 was 1.47 per 100,000 population in Japan. The average age at onset was 71.5 years old. The male:female ratio was 1:1.7. The association with permanent and complete visual loss (6.5%), jaw claudication (15.2%), and polymyalgia rheumatica (PMR) (30.3%) were low in frequency compared with those reported from other countries. All patients were treated with corticosteroids. Only 3 (4.5%) patients were reported as deceased due to other causes. Conclusion. The prevalence of GCA in Japan was revealed to be extremely low compared with other countries. Clinical findings of permanent and complete visual loss, jaw claudication, and PMR were infrequent among Japanese patients with GCA.