Objectives: To assess the prevalence of Kennedy's disease in the Vasa region of Western Finland.
Patients and methods: Verification of diagnosis by molecular genetic techniques since 1995.
Results: Within 2 years we have been able to identify a large number of families with this disorder. We have arrived at a point prevalence of Kennedy's disease in the district of Vasa Central Hospital of 13 patients per 85,000 male inhabitants. Assuming an even distribution throughout the country, this would suggest hundreds of patients with this disorder in Finland.
Conclusion: Kennedy's disease is the most common motor neuron disorder in the Vasa region, exceeding the prevalence of ALS by a factor of two, and far more common than any of the other motor neuron disorders. The fact that none of our patients, despite previous examinations, had correct diagnoses before 1995, indicates that Kennedy's disease still might be relatively underdiagnosed.