Outcomes After Seizure Recurrence Upon AED Withdrawal Following Temporal Lobectomy

The majority of patients with mesial temporal lobe epilepsy who experience seizure recurrence during antiepileptic drug (AED) withdrawal after an anterior temporal lobectomy become seizure-free, and a minority of patients become drug-free following seizure recurrence, according to a study published in Neurology.

In the retrospective study, investigators analyzed 5-year follow-up data of 384 consecutive patients who underwent anterior temporal lobectomy for mesial temporal lobe epilepsy between 1995 and 2005. Patients included in the analysis had hippocampal sclerosis or normal magnetic resonance imaging (MRI). At 3 months, AED withdrawal was initiated in patients taking ≥2 drugs. Withdrawal from AEDs was also initiated at 1 year in patients taking a single drug.

During a median postoperative 12-year follow-up, a total of 316 (82.3%) patients attained seizure-free and aura-free status during the terminal year, and 234 (60.9%) patients achieved terminal remission at 5 years. Additionally, 177 (46.1%) patients were free from seizures or aura after intervention. Discontinuation of AEDs occurred in 53.9% of the entire cohort at the last follow-up evaluation.

Recurrence of seizures was reported in 28.2% (n=92) of patients who attempted withdrawal. Of these patients, 86% (n=79) of patients achieved a seizure-free status during the terminal 2 years and after a median postrecurrence 7-year follow-up. A total of 17 (18.5%) patients had AEDs discontinued, and 57 (62%) patients had their doses reduced. A 17% risk of seizure recurrence on AED withdrawal was observed in patients with a normal electroencephalogram (EEG) at 1 year after initial operation, in patients with febrile seizures, and in patients with an epilepsy duration of <20 years.

In the multivariate analysis, the predictors of seizure recurrence included having an epilepsy duration of >20 years (odds ratio [OR] 1.8; 95% CI, 1.1-3.1; P =.022), absence of febrile seizures (OR 1.8; 95% CI, 1.1-2.9; P =.031), and interictal epileptiform discharges on 1-year EEG (OR 2.2; 95% CI, 1.1-4.2; P =.018).

The study’s main limitations include its observational and retrospective nature, which limits the conclusivity of the findings.

According to the researchers, the findings from the study may be “useful in identifying patients who have a lower chance of recurrence on attempted AED withdrawal,” considering that “not all seizure-free patients can be continued on AEDs indefinitely.”

Reference

Rathore C, Jeyaraj MK, Dash GK, et al. Outcome after seizure recurrence on antiepileptic drug withdrawal following temporal lobectomy. Neurology. 2018;91:e208-e216.