Abstracts

Rationale: Factors influencing the discontinuation of antiepileptic drugs (AEDs) after mesial temporal lobe epilepsy (MTLE) surgery varied and driven usually by the patient’s desire, for which we aimed to identify these factors. Methods: A retrospective chart review was performed of patients with MTLE who underwent anterior temporal lobe resection between 2005 to 2017, with at least 12 months follow up, but only those with complete medical records were studied. Results: Eighty patients with MTLE who had epilepsy surgery were identified, but only 44 patients who had complete data were studied. There was 29 (66%) men, with mean age at time of surgery of 32 years (range; 16-54 years), and mean age at epilepsy onset of 12 years (range; 1-36 years). Patients were followed for 1-10 years. The average number of AEDs prior to surgery was 2 (range; 1-4), and the average seizure frequency per month was 10 (range; 2.5 – 30). The first tapering of AEDs started at 3 months after the surgery (mean of 10 months), where it was attempted in all except 10 (23%) patients. On average, 18 months were required to completely taper AEDs, but only 19 (43%) patients were seizure-free and off medications. Multiple linear regression analysis showed that MTLE caused by cortical dysplasia required 8.4 months more than MTLE with hippocampal sclerosis to start tapering AEDs (p < 0.01, 95% CI; 2.2 – 21.2). On the contrary, the time required to be off AEDs was associated only with hippocampal sclerosis (7 months, 95% CI; 0.5 – 21, p < 0.01). Conclusions: In our cohort, pathological substrates only could determine the time required to start tapering AEDs till discontinuation following MTLE surgery. Larger cohort studies are required to confirm these observations. Funding: No funding