Myasthenia gravis in the elderly: a hospital based study.

To evaluate clinical characteristics and outcome of myasthenia gravis (MG) in aged patients (> 60yrs), we retrospectively reviewed a continuous series of 122 myasthenic patients observed from January 1968 through December 1994. Patients with congenital, neonatal, or penicillamine-induced myasthenia were excluded. Twenty-five subjects (20%) were > 60yrs. The male/female ratio was 3:2; 20% of patients had an ocular form and 86% were seropositive. Mediastinum CT scan revealed thymic changes in 14%. During the first five years of disease, 60% of patients with ocular form progressed towards a generalized form and 15% had clinical relapses. At the time of their last visit, 40% of patients were asymptomatic and 60% had improved on medication. No patient died because of myasthenia-related causes. This study shows that MG in aged patients is characterized by prevalence in males, low frequency of ocular forms, low frequency of positive mediastinum CT which suggests low frequency of thymomas, high frequency of progression of ocular forms, and good response to corticosteroid therapy.