Outcomes after discontinuation of antiepileptic drugs after surgery in patients with low grade brain tumors and meningiomas.

Low grade tumors are associated with a high risk of seizures. Prolonged use of antiepileptic drugs (AEDs) is associated with morbidity. Determining which patients can safely discontinue AEDs perioperatively is difficult. We examined patients with low grade supratentorial brain tumors to determine characteristics of patients who underwent AED withdrawal. A retrospective chart review was performed in patients who underwent resection between 1/1/2004 and 12/31/2005 at a single center. Data were collected regarding the use of postoperative AEDs, occurrence of postoperative seizures, and patient/tumor characteristics. We examined 169 patients with a median follow-up of 3.1 years. AEDs were withdrawn or never started in 111 patients; post-withdrawal seizures occurred in 11 (9.9%). The rate was similar between meningiomas and primary brain tumors. No independent risk factors for post-withdrawal seizures were found. Of 58 patients whose AEDs were not withdrawn, postoperative seizures occurred in 28 (48%). Predictors of AED continuation included existence of preoperative seizures, temporal tumor location, tumor recurrence, incomplete resection, and male sex. The decision to continue AEDs was predictive for postoperative seizures even after controlling for known risk factors. Although clinicians are able to identify patients at high risk for postoperative seizures, treatment with AEDs is ineffective in many patients.