Antiepileptic drugs and relapse after epilepsy surgery

To evaluate whether the postoperative, antiepileptic drug (AED) regimen influences seizure recurrence after anterior temporal lobectomy when considering the putative mechanism of action and possible neuroprotective effects.

This was a retrospective study. Patients who had an anterior temporal lobectomy for refractory epilepsy, whose preoperative MRI indicated mesial temporal sclerosis, were included. Postoperative AED regimens were compared with regard to seizure-outcome, considering the putative mechanism of action (sodium channel blockers, non-sodium channel blockers, and mixed mechanisms) or possible neuroprotective effect (levetiracetam, topiramate, tiagabine and zonisamide versus others). Time-to-event (first seizure after surgery) analysis was used to produce a Kaplan-Meier estimate of seizure recurrence, and groups were compared using Cox proportional hazard analysis.

226 patients (103 males and 123 females; mean age 42 +/- 11 years) were studied. The rates of postoperative seizure recurrence were not significantly different between the three groups regardless of the use of AEDs with different mechanisms of action (p = 0.23). Fifty patients were receiving possibly neuroprotective AEDs and 176 patients were not. Rates of seizure recurrence were not significantly different between these two groups either (p = 0.11). The differences between one-year seizure-free rates were not significant when we compared levetiracetam versus phenytoin or carbamazepine.

There appeared to be no advantage or disadvantage to either prescribing drugs with different mechanisms of action or using drugs with possible neuroprotective effect after temporal lobectomy. Prospective studies with larger sample sizes may be of benefit to further explore this issue.