Late-onset epilepsy: etiologies, types of seizure, and value of clinical investigation, EEG, and computerized tomography scan.

Approximately 25% of patients with epilepsy will have their first seizure after the age of 25 years. These individuals will need special attention with regard to etiology. Brain tumor is one of several causes that may be suspected. The present study of 221 patients with late-onset epilepsy from the University Clinic of Neurology, Hvidovre Hospital, Copenhagen, Denmark, was undertaken to look for means to select those cases in which computerized tomography (CT) scan should be performed. Brain tumor was the cause in 16% and cerebrovascular infarctions in 14%. The major etiological group was the one in which no cause could be detected (38%). Alcohol abuse as the etiology--defined as cases with a history of long-standing alcohol overuse, concomitant signs of alcohol intoxication, and spontaneous recurrent epileptic seizures--made up a group of one-fourth of all the patients with late-onset epilepsy. Comparison of the history, clinical symptoms and signs, EEG abnormalities, and CT scan speaks in favor of some consideration being given to the first three parameters before the CT scan is performed.