Valproate decreases vitamin D levels in pediatric patients with epilepsy.

PURPOSE To compare Vitamin D (Vit D) levels in children with epilepsy on valproate monotherapy with healthy controls. METHODS A meta-analysis performed on articles identified from PubMed and Web of Science online databases evaluated using National Institute of Health National Heart, Lung, and Blood Institute Study Quality Assessment Tools. Subgroup analyses and publication bias assessments were also performed. RESULTS Eleven publications were eligible based on inclusion/exclusion criteria for the meta-analysis. Results noted a decrease in the mean Vit D level in children with epilepsy on valproate monotherapy compared with healthy children with a Standard Mean Difference = -0.313 [-0.457, -0.169]. Cumulative meta-analysis showed progressive negative effect of valproate therapy on Vit D levels across time. Other antiepileptic medications caused a similar effect on Vit D status. There was no evidence of publication bias in the analyses. Type of study design and country of origin introduced heterogeneities into the meta-analyses. CONCLUSION This meta-analysis provides evidence that long-term therapy with valproate causes a decrease in Vit D levels in children. Therefore, in children with a seizure disorder on long-term valproate therapy, 25-OH-Vit D levels should be monitored and appropriate supplementation implemented if levels are deficient.