Seizure recurrence risk in persons with epilepsy undergoing antiepileptic drug tapering

Antiepileptic drug (AED) tapering in persons with epilepsy (PWE) after 2-3 years of seizure freedom is still debatable because of the risk of seizure recurrence. Tapering patterns have wide variability and could impact seizure recurrence; this study aimed to find out the correlation between them.

This prospective, observational independent assessor study enrolled PWE undergoing AED tapering in a tertiary care hospital. Data collected included demography, seizure history, AED treatment, and investigational findings. Tapering pattern was assessed based on seizure-free period and AED dose before onset of tapering, dose reduction percentage and frequency, duration of tapering, and follow-up. These variables were compared among the PWE with seizure recurrence and no seizure recurrence.

Among 408 enrolled PWE, 181 were on AED monotherapy: levetiracetam (73), valproate (45), carbamazepine (44), phenytoin (16), and clobazam (3). With a minimum 19 (maximum 41 months) follow-up, seizure recurrence was reported in 119 (29.2%) PWE. The seizure recurrence was not significantly different in-between mono and polytherapy groups; however, among monotherapy groups seizure recurrence was significantly higher (P = .023) in valproate (35.5%) followed by levetiracetam (28.8%) group. Parameters having significant association with seizure recurrence were duration of epilepsy (P = .03), frequency of seizures before control (P = .002), history of previously failed tapering (P = .04), and history of smoking/alcoholic/tobacco intake (P = .003).

There is a wide variation in AEDs tapering pattern and seizure recurrence risk can be minimized by considering the risk factors like history of smoking/alcoholic/tobacco, longer duration of epilepsy, frequency of seizures before control, and previously failed tapering.