Abstracts

Rationale: Retrospective case studies suggest that epilepsy may remit in childhood only to return with a vengeance in adulthood. We used a prospective population-based study to address the magnitude of this concern. Methods: The Nova Scotia Childhood study of children with epilepsy provided data on all children who developed epilepsy in this province between 1977-85. We selected patients with ?-20 follow up and included all types of epilepsy except childhood absence. Results: 388 of 544 (70%) met the entry criteria with an average follow up of 284 years at which point they averaged 34 6.5 years of age. 296 (76%) had a ?-5 year remission at some point in their course (AED treatment). The duration of remission ?-5 years averaged 218 years with 89% no longer receiving AEDs at the end of follow up. Of those with ?-5 year remission, 265/296 (90%) had no further seizures, while 31 (10%) later had ?-1 seizures. The average time from seizure onset to the beginning of ?-5 year remission was 7 years (median 4 years, range 0.1-30 years); however, 98/388 (25%) had ?-5 year remission beginning =1 year after seizure onset. A total of 45/388 (12%) had "smooth sailing epilepsy" which meant that they had no further seizures after AED treatment was started. Prior to the beginning of a ?-5 year remission, the average number of AEDs was 1.91.3 (median 2). 11/388 underwent epilepsy surgery but 0/11 had a ?-5 year remission before their surgery. Only 7/296 (2%) had intractable epilepsy at the end of follow up after ?-5 year remission (5 with focal epilepsy, 1 symptomatic generalized, 1 unclassified). The duration of their remission was 5 years median, range 5-18 years. By contrast, in the overall sample of 388 there were 332 (86%) who had a remission of ?-2 years during their clinical course and yet following this remission, 23 (7%) had intractable epilepsy at the end of follow up. Conclusions: The Nova Scotia population-based study indicates that during a follow up of >25 years, 76% of children with epilepsy will have a ?-5 year remission with a mere 2% later developing intractable epilepsy. A family "sigh of relief" is reasonable after 5 years without seizures although it is never possible to absolutely guarantee a permanent remission. Funding: no funding