Very late-onset autoimmune myasthenia (VLOM) is becoming increasingly common:
- appears from the age of 65 onwards,
- is characterised by a male predominance and a rare association with thymoma,
- should be considered in any elderly patient presenting with recent localised or generalised muscle weakness, with testing for anti-RACh antibodies being essential,
- generally has a good prognosis,
- but must be treated actively and early as short-term mortality (within the first year) remains high due to the potential severity of the disease (initial respiratory failure in 1 in 5 cases) or iatrogenic complications.
The management of anti-RACh+ elderly patients is based on the same principles as that for younger patients (cholinesterase inhibitors, first-line immunosuppressants, etc.). Rituximab, complement inhibitors and anti-FcRn antibodies may be used for the same indications. A programme of adapted physical activity is recommended once the disease has stabilised.
Myasthénie du sujet âgé. Salort Campana E. La lettre du neurologue, février 2026