Abstracts

Epilepsy is defined by unprovoked recurrences of epileptic seizures, but its natural history varies widely. Even within the same epilepsy syndrome, some patients will remit and can discontinue AED (antiepileptic drug) treatment, while others will prove refractory. Prompt control of seizure recurrences has been recognized as the most significant predictor of remission, but some can enjoy clinical seizure control, only when AED prophylaxis is continued. The latter group of patients is not well characterized, even though they benefit most from the epileptologist[apos]s expertise., The author[apos]s epileptology practice data were reviewed for patients with the following characteristics: 1) follow-up record spanning a period longer than 10 years, 2) the diagnosis of epilepsy has been based not only on clinical semiology, often confirmed by EEG findings, but also on sporadic clinical recurrences, when AED treatment is interrupted, and 3) interative AED trials led to a terminal prophylactic single AED regimen., A total of 6530 adult patients had been screened prior to 1996 by the author, based at a University Hospital. Also generated were a total of 43101 AED treatment history entries for 916 patients, in 377of whom computer medical record was accessible for the most recent visit. The 10-year time span criterion narrowed the list down to 87. After patients with multiple developmental handicaps or unconfirmed epilepsy diagnosis, and those having undergone resection brain surgery were excluded, there remained 31 patients (31/377 = 8.2 %). Their terminal AED regimens consisted of phenytoin (15 patients), carbamazepine (12), phenobarbital (3) or valproic acid (2)., As a consultative service, the clinic has not consistently extended clinical follow-up, once a degree of seizure control was attained. The result (8.2 %) is therefore assumed to underestimate the prevalence of this significant group of patients. The time span criterion, not the lack of efficacy, excluded monotherapy with a second generation AED. Also excluded was a group of patients on 2 AED with an essentially similar degree of excellent clinical control. This may explain a smaller group size of valproic acid monotherapy. This group of patients does not seem to require aggressive AED dosing nor report AED-related adverse symptoms, but represents the failure of efforts to wean off AED. They come to recognize, and fear, inevitable clinical recurrences off AED. They are typically protective of their AED regimen, and may well opt not to continue to work with the epileptologist. Sporadic seizure recurrences seem to occur often during attempts to replace AED with a second generation agent.,