Natural History and Prognosis of Epilepsy: Report of a Multi-institutional Study in Japan.

Abstract

A multi-institutional study on the prognosis of patients with epilepsy was performed in Japan from 1975-1977, including 20 institutions. The outcome of epileptic seizures and social adjustment 10, 5 and 3 yr after the onset of the illness was studied in 3 different groups of epileptic patients, respectively. The number of successfully followed-up cases was 1868 in total, follow-up rate being 42%. The data were analyzed statistically by use of analysis of variance. The rate of remission of seizures in all was 58.3% and the rate of normal social adjustment 62.6%. The remission rate showed no significant difference among 10, 5 and 3 yr outcome groups. The prognosis of seizure control is apparently more favorable; in idiopathic than in residual or symptomatic epileptics; in patients with onset before 10 yr of age than in those with onset after 10 yr; in patients with less frequent seizures; in sleep epilepsy within 1 yr of onset of seizure; in patients with single-type partial seizures than in those with partial seizures combined with tonic-clonic seizures; in patients without high grade EEG background abnormality; and in patients without neurological symptoms, intellectual deficits, personality disturbances or psychotic symptoms. Factors that determine the prognosis of social adjustment were almost similar to those for remission of seizures. There was a close correlation between the outcome of seizure control and that of social adjustment. Correlations coefficient between follow-up rate and remission rate in 15 of the 20 collaborated institutions was 0.55 (P < 0.05), showing a tendency that the remission rate becomes higher as the follow-up rate is raised.