OBJECTIVE: To clarify the prevalence and clinical characteristics of myasthenia gravis (MG) in Japan. METHODS: We performed a nationwide epidemiological survey of MG in Japan. The clinical features were compared among five groups of patients, divided according to onset age. A generalized additive model (GAM) was used to assess the linearity of these relationships. RESULTS: A total of 8542 patients were reported, and detailed data were analyzed for 3141 patients. The estimated number of MG patients in Japan was 15,100, giving a prevalence of 11.8 per 100,000. Elderly-onset MG (≥ 65 years) accounted for 7.3% in 1987 (adjusted for population in 2005), but this had increased to 16.8% in 2006. Infantile-onset MG (0-4 years) accounted for 10.1% in 1987, and was still as high as 7.0% in 2006. The rate of ocular MG was highest (80.6%) in infantile-onset and lowest (26.4%) in early-onset disease, but the rate rose again in the late-onset group. GAM analysis of the ocular form showed a U-shaped curve, with a dip in the 20s. Anti-acetylcholine receptor antibodies were positive in only 50% of infantile-onset, but nearly 90% of elderly-onset patients. GAM analyses assessing the concurrence of thymoma and hyperplasia both showed reversed U-shapes, with peaks in the 50s and 20s-40s, respectively. CONCLUSIONS: Persistent high incidence of infantile-onset disease and clinical heterogeneity according to onset age are characteristic features of MG in Japan.
OBJECTIVE: To clarify the prevalence and clinical characteristics of myasthenia gravis (MG) in Japan. METHODS: We performed a nationwide epidemiological survey of MG in Japan. The clinical features were compared among five groups of patients, divided according to onset age. A generalized additive model (GAM) was used to assess the linearity of these relationships. RESULTS: A total of 8542 patients were reported, and detailed data were analyzed for 3141 patients. The estimated number of MG patients in Japan was 15,100, giving a prevalence of 11.8 per 100,000. Elderly-onset MG (≥ 65 years) accounted for 7.3% in 1987 (adjusted for population in 2005), but this had increased to 16.8% in 2006. Infantile-onset MG (0-4 years) accounted for 10.1% in 1987, and was still as high as 7.0% in 2006. The rate of ocular MG was highest (80.6%) in infantile-onset and lowest (26.4%) in early-onset disease, but the rate rose again in the late-onset group. GAM analysis of the ocular form showed a U-shaped curve, with a dip in the 20s. Anti-acetylcholine receptor antibodies were positive in only 50% of infantile-onset, but nearly 90% of elderly-onset patients. GAM analyses assessing the concurrence of thymoma and hyperplasia both showed reversed U-shapes, with peaks in the 50s and 20s-40s, respectively. CONCLUSIONS: Persistent high incidence of infantile-onset disease and clinical heterogeneity according to onset age are characteristic features of MG in Japan.
Authors: Elena Cortés-Vicente; Rodrigo Álvarez-Velasco; Sonia Segovia; Carmen Paradas; Carlos Casasnovas; Antonio Guerrero-Sola; Julio Pardo; Alba Ramos-Fransi; Teresa Sevilla; Adolfo López de Munain; Maria Teresa Gómez; Ivonne Jericó; Gerardo Gutiérrez-Gutiérrez; Ana Lara Pelayo-Negro; María Asunción Martín; María Dolores Mendoza; Germán Morís; Ricard Rojas-Garcia; Jordi Díaz-Manera; Luis Querol; Eduard Gallardo; Beatriz Vélez; María Antonia Albertí; Lucía Galán; Tania García-Sobrino; Alicia Martínez-Piñeiro; Ana Lozano-Veintimilla; Roberto Fernández-Torrón; Ángel Cano-Abascal; Isabel Illa Journal: Neurology Date: 2020-02-18 Impact factor: 9.910
Authors: Djingri Labodi Lompo; Nagaonlé Éric Some; Adja Mariam Ouedraogo; Rodrigue P Yonli; Ousséini Diallo; Christian Napon; Athanase Millogo; Jean Kabore Journal: Med Trop Sante Int Date: 2021-11-11