PubMed2026
INTRODUCTION: Juvenile myoclonic epilepsy (JME) is a genetic generalized epilepsy syndrome with onset typically in adolescence and a chronic course requiring long-term antiseizure medications (ASMs). Valproate (VPA) is the most effective treatment for seizure control in JME but use is limited by metabolic, cognitive, and teratogenic adverse effects (AEs). Levetiracetam (LEV) is an alternative ASM when VPA is contraindicated or not tolerated. Comparisons of the efficacy and long-term tolerability of VPA and LEV remain limited. METHODS: We conducted a systematic review and meta-analysis using PRISMA guidelines and the Cochrane Handbook. We searched PubMed, Embase, and the Cochrane Library from inception through January 2026 for studies in JME patients comparing LEV and VPA, and included randomized controlled trials and comparative observational studies with ≥ 6 months of follow-up. Primary outcomes were seizure remission and ASM failure or treatment discontinuation. Secondary outcomes included, memory impairment, weight gain or obesity, dizziness, and overall AEs. Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled using random-effects models. Heterogeneity was assessed using the I2 statistic. RESULTS: Seven studies encompassing 1,009 patients were included. VPA was associated with higher pooled seizure remission rates compared with LEV (344 of 574 vs. 169 of 390; RR 1.44, 95% CI 1.27-1.63); however, substantial heterogeneity (I2 = 88.4%) limits confidence in this finding. VPA was associated with a lower risk of drug failure or treatment discontinuation (RR 0.68, 95% CI 0.54-0.86), with no heterogeneity (I2 = 0.0%). VPA was also associated with a higher risk of memory impairment (RR 5.37, 95% CI 2.05-14.04; I2 = 74.5%) and weight gain or obesity (RR 6.40, 95% CI 3.64-11.26; I2 = 35.9%). No significant differences were observed between treatments regarding dizziness (RR 0.91, 95% CI 0.61-1.37; I2 = 21.2%). Sensitivity analyses confirmed the robustness of the pooled estimates. CONCLUSION: VPA was associated with higher seizure remission rates and lower treatment discontinuation compared with LEV; however, these findings must be interpreted with caution given the substantial heterogeneity, the predominance of observational studies, and the serious risk of bias identified in most included studies VPA also demonstrated lower rates of treatment discontinuation, despite a higher burden of cognitive impairment and weight gain. No relevant differences were observed regarding dizziness. Large-scale randomized trials with standardized outcome definitions and longer follow-up are needed to define the comparative risk-benefit profiles of LEV and VPA in JME.