| Prevalence | 4-6 per 100,000 population |
| Incidence | 1-2 per 100,000 annually |
| Age of onset | Typically 55-60 years (younger than bulbar onset) |
| Gender distribution | Male predominance (1.5-2:1) |
| Geographic variation | Higher incidence in some populations (e.g., Guam, Kii Peninsula) |
| Databases | OMIMOrphanetClinicalTrialsPubMed |