| Prevalence | 2-5 per 100,000 |
| Annual incidence | 0.6 per 100,000 |
| Mean age at onset | 53-64 years |
| Gender distribution | Slight male predominance (1.3-1.5:1) |
| Geographic variation | MSA-C more common in Japan; MSA-P more common in Western countries |
| Disease duration | Median 6-10 years from onset |
| Databases | OMIMOrphanetClinicalTrialsPubMed |