Late-onset myasthenia gravis: Is it a different clinical entity?

Objective: The increase in the average life expectancy of humans has resulted in an increased occurrence of late-onset myasthenia gravis (LOMG). It is noticeable that the clinical, immunologic, and prognostic features of patients with LOMG are different than those of the patients with early-onset myasthenia gravis (EOMG). The present study aimed to establish the dissimilar features of patients with EOMG and LOMG. Subjects and Methods: The study retrospectively compared 93 patients with EOMG and LOMG in terms of clinical and immunologic features and response to medical treatment and thymectomy. Results: Of the 93 patients with MG, 56 had EOMG and 37 had LOMG. The EOMG group was dominated by female patients and generalized MG, whereas male patients and ocular MG were predominant in the LOMG group. Both groups tested positive for acetyl choline receptors antibodies. The number of patients undergoing thymectomy was higher in the EOMG group than in LOMG group. Responses to thymectomy and immunosuppressive treatment in LOMG group were lower compared with the EOMG group. Conclusion: The present study concludes that the clinical prognosis of patients with LOMG is better, and thymectomy may not be quite necessary for patients in this group who do not have thymomas (nonthymomatous patients).