Prevalence of epilepsy in rural Iceland: a population-based study

To determine the prevalence of epilepsy (recurrent unprovoked seizures) in the population of rural Iceland.

Review of records of primary-care facilities for the population of rural Iceland supplemented by review of referrals to electroencephalographic facilities and neurologic specialists to identify all individuals with unprovoked seizures or receiving treatment for epilepsy in the calendar year 1993.

Crude prevalence was 4.8 per 1,000 and was 4.8/1,000 after age adjustment to the 1970 United States population. Age-adjusted prevalence was higher in male (5.1) than in female subjects (4.4) and increased with advancing age. Sixty-two percent of prevalence cases were of unknown cause. Sixty-three percent of cases had major motor seizures without aura or generalized epileptiform pattern on EEG. Sixty-four percent of patients had had seizures in the year of observation. Seizure control was inversely correlated with number of medications. Ten percent of the prevalence group was taking no medication, although the frequency of seizures was high in this medication-free group.

Prevalence of epilepsy in rural Iceland is consistent with that reported in recent studies in other developed countries. The data provide insights into the approaches of treatment and use of specialized diagnostic testing in the country. The prevalence is similar to that in other European countries but lower than that reported from rural areas in Latin America.