Incidence and prevalence of epilepsy in adults in eastern Finland.

In Finland, only limited data exist on the epidemiology of epilepsy in adults. This prompted us to study the incidence and prevalence of epilepsy in a population over 15 years of age, residing in Eastern Finland. In a retrospective study, various medical data sources were used to identify and reexamine all patients with established or suspected epileptic seizures during 1960-1979. A total of 1,233 patients with active epilepsy were identified. Mean annual incidence of epilepsy was 24/100,000. Age-specific incidence ratios tended to increase with advancing age. Prevalence of active epilepsy was 629/100,000. Both prevalence and incidence were higher in males than in females. Age-specific prevalence of active epilepsy increased until 40-50 years of age, and declined in the oldest age groups. Of the various seizure types, highest prevalence ratios were observed for partial secondarily generalized seizures, complex partial seizures, and tonic-clonic seizures. Prevalence of partial seizures and generalized seizures had a different age-related pattern.