The frequency of intractable seizures after stopping AEDs in seizure-free children with epilepsy.

Background: After 1 to 4 years, seizure-free children with epilepsy are encouraged to stop daily antiepileptic drug (AED) treatment. Approximately 70% are successful. The authors examined how often intractable epilepsy follows discontinuation of AED treatment in a population-based cohort of children with epilepsy.

Methods: The Nova Scotia population-based epilepsy cohort was used to identify children who discontinued AEDs but subsequently developed intractable epilepsy. All patients studied (ages 1 month to 16 years) developed epilepsy between 1977 and 1985, had epilepsies characterized by partial or convulsive seizures, and had at least 5 years of follow-up evaluation (n = 367). Those with benign rolandic epilepsy were excluded. Intractability was defined as one or more seizures every 3 months during the last year of follow-up review or until successful seizure surgery and failure of three or more AEDs at maximum tolerated doses.

Results: Overall, 71% (260/367) of eligible children became free of seizure for 1 to 4 years and discontinued AED treatment. Of this group, 70% remained seizure-free without AED treatment, but 30% had recurrences. Only three children with recurrences later developed intractable epilepsy. Two then underwent a temporal lobectomy, one successful and one only partially successful (20-year follow-up periods). The third patient continued to have intractable epilepsy for 7 years after discontinuing AED treatment but eventually entered remission.

Conclusion: Approximately 1% of children who became free of seizure and discontinued antiepileptic drug treatment had recurrent seizures that could not be controlled again with medication. The authors were unable to predict this outcome. It remains unclear whether a similar outcome would have occurred if antiepileptic drugs had not been discontinued.