Antiepileptic drug monotherapy for epilepsy in the elderly: A systematic review and network meta-analysis

Objective: To estimate the comparative efficacy and safety of antiepileptic drugs (AEDs) in the elderly with new-onset epilepsy.

Methods: We searched electronic databases for randomized controlled trials (RCTs) of monotherapy AEDs to treat epilepsy in elderly. The following outcomes were analyzed: seizure freedom and withdrawal from the study for any cause at 6 and 12 months; withdrawal from the study for any adverse event (AE) at 12 months; and occurrence of any AE at 12 months. Effect sizes were estimated by network meta-analyses within a frequentist framework. The hierarchy of competing interventions was established using the surface under the cumulative ranking curve (SUCRA) and mean ranks.

Results: Five RCTs (1425 patients) were included. Included AEDs were carbamazepine immediate- and controlled-release (CBZ-IR, CBZ-CR), gabapentin (GBP), lacosamide (LCM), lamotrigine (LTG), levetiracetam (LEV), phenytoin (PHT), and valproic acid (VPA). At the pairwise and network meta-analyses, there were no differences in any of the comparison according to 6- and 12-month seizure freedom. The treatment with CBZ-IR and CBZ-CR was associated with a higher risk of withdrawal than LTG, LEV, or VPA, and CBZ-IR had the overall highest probability of discontinuation across all AEDs. According to SUCRA, the following had the greatest likelihood ranking best for seizure freedom at 6 and 12 months: LCM, LTG, and LEV. CBZ-CR and CBZ-IR had the highest probabilities of being worst for the 12-month retention. CBZ-IR, CBZ-CR, and GBP had the highest probabilities of withdrawal from the study for AEs, , and VPA had the highest probability of being the best-tolerated option.

Significance: Although no significant difference in efficacy was found across treatments, LCM, LTG, and LEV had the highest probability of ranking best for achieving seizure freedom. CBZ-IR and CBZ-CR showed a poor tolerability profile, leading to higher withdrawal rates compared to LEV and VPA.