Lamotrigine versus valproic acid monotherapy for generalised epilepsy: A meta-analysis of comparative studies

The standard for generalized epilepsies (GE) monotherapy in treatment is valproic acid (VPA) and lamotrigine (LTG) has been proposed as an alternative to VPA. This study aimed to evaluate the safety and efficacy of LTG on GE seizure in comparison with VPA.

A search was conducted based on the databases from Pubmed, Embase and the Cochran database up to February 2017. The relative risk odds ratios (ORs) and the relevant 95% confidence intervals (CI) were determined.

Five randomized controlled trials and four observational cohort studies involving 1732 cases were included. The results indicated that VPA was significantly superior to LTG for the outcome rate to treatment withdrawal for any reason and seizure freedom. The ORs and 95% CI of VPA versus LTG for withdrawal after 12- and 24-month treatment were 0.39(0.27, 0.56) and 0.50(0.14, 1.75), respectively, and were 3.51(2.68, 4.59) and 8.58(5.40, 13.63)for 12- and 24- month seizure free intervals, respectively. Moreover, the risk of adverse effects (OR (95%CI); 1.11(0.61-2.01)) was not significantly different between the two groups. However, the treatment withdrawal due to lack of seizure control were in the LTG group (OR (95%CI); 0.15(0.10-0.23)), while the treatment withdrawal due to intolerable side effects were in the VPA group (OR (95%CI); (1.75(1.10-2.80)).

The meta-analysis suggests that VPA appears to be a better choice in controlling seizure following GE. However, therapy should be switched to alternative monotherapy if an adequate trial of VPA monotherapy is not effective and intolerable, especially in young women.