Hiroyuki Tomimitsu1, Akiko Ohta2, Masaki Nagai2, Motoko Nishina2, Shoichiro Ishihara3, Hitoshi Kohsaka4. 1. a Department of Neurology , JA Toride Medical Center , Toride City , Ibaraki , Japan . 2. b Department of Public Health , Saitama Medical University Faculty of Medicine , Moroyama-Machi , Iruma-Gun , Saitama , Japan . 3. c Department of Neurology and Neurological Science , Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University , Bunkyo-Ku , Tokyo , Japan , and. 4. d Department of Medicine and Rheumatology , Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University , Bunkyo-Ku , Tokyo , Japan.
Abstract
OBJECTIVES: This study aimed to investigate the clinical characteristics of polymyositis/dermatomyositis (PM/DM) in Japan by analyzing data from the nationwide registration system. METHODS: The data of the registration system in 2009 were analyzed to investigate patient numbers, sex, clinical symptoms, therapies, complications, and prognosis of PM/DM. RESULTS: The total number of PM/DM cases was approximately 17,000, and the female/male sex ratio was 2.7:1. Almost all patients improved as a result of therapy, but many suffered from sequelae such as muscle weakness. CONCLUSIONS: The results characterize significant aspects of Japanese PM/DM patients. However, a further prospective survey is required to clarify the true epidemiology and natural history of PM/DM.
OBJECTIVES: This study aimed to investigate the clinical characteristics of polymyositis/dermatomyositis (PM/DM) in Japan by analyzing data from the nationwide registration system. METHODS: The data of the registration system in 2009 were analyzed to investigate patient numbers, sex, clinical symptoms, therapies, complications, and prognosis of PM/DM. RESULTS: The total number of PM/DM cases was approximately 17,000, and the female/male sex ratio was 2.7:1. Almost all patients improved as a result of therapy, but many suffered from sequelae such as muscle weakness. CONCLUSIONS: The results characterize significant aspects of Japanese PM/DMpatients. However, a further prospective survey is required to clarify the true epidemiology and natural history of PM/DM.