Long-term outcome in adolescent-onset generalized genetic epilepsies.

Objective: Until now, it has been unclear if the three subsyndromes of adolescent-onset generalized genetic epilepsy (GGE) differ in long-term prognosis. Therefore, this study aimed to compare long-term seizure outcome in juvenile absence epilepsy (JAE), juvenile myoclonic epilepsy (JME), and epilepsy with generalized tonic-clonic seizures alone (EGTCS).

Methods: This retrospective study is based on the archive of an institutional tertiary care outpatient clinic for adult patients with epilepsy. Charts of 870 epilepsy outpatients were reviewed among whom 176 had adolescent-onset GGE (53 JAE, 66 JME, 57 EGTCS). Median patient age at investigation was 60 years; median follow-up time was 42.5 years. If possible, GGE patients were additionally interviewed on psychosocial and clinical variables.

Results: Age at first seizure was significantly higher in EGTCS patients (median 18 years) than in patients with JAE or JME (14 years each; p ≤ 0.001). Long-term seizure outcome hardly differed between the three subsyndromes. At the end of follow-up, 60% of all patients were in 5-year terminal seizure remission, and in 14%, epilepsy even had resolved (>10 years without seizures, >5 years without pharmacotherapy). Twenty percent of patients had persistent seizures during the last year of follow-up. Across all patients, 23% reported a psychiatric comorbidity, 87% had married, and 57% had achieved university entrance qualification.

Significance: Long-term outcome was shown to be highly similar across all subsyndromes of adolescent-onset GGE. Even in a selection of difficult-to-treat epilepsy patients still attending an adult epilepsy clinic, most become seizure-free. To confirm these findings, prospective studies are needed.