Vitamin D deficiency in children with epilepsy taking valproate and levetiracetam as monotherapy

The aim of this study is to evaluate if valproate (VPA) and levetiracetam (LEV) as monotherapy are associated with vitamin D deficiency among children with epilepsy.

A cross-sectional clinical (seizure types, aetiology of epilepsy, dosage, drug levels, and duration of AED treatment) and blood testing (calcium, phosphorus, 25-OHD and PTH) study was accomplished in 90 epileptic children (AED group: 59 receiving VPA, and 31 receiving LEV) and a control group (244 healthy subjects). 25-OHD levels were categorized as low (<20ng/ml), borderline (20-29ng/ml), or normal (>30ng/ml) RESULTS: The average dosage of VPA and LEV was 20.7±4.7mg/kg/d and 24.1±7.9mg/kg/d, respectively. The mean duration of VPA therapy was 2.5±1.4years, and with LEV was 2.3±1.6years. Mean calcium and 25-OHD levels were significantly higher (p <0.05) in the control group. There was a negative correlation (p <0.01) between 25-OHD and VPA levels (r=-0.442). Vitamin D deficiency (%) was significantly higher (p <0.05) in VPA (24.1%) and LEV (35.5%) groups than in control group (14%). The multiple logistic regression analysis showed that VPA monotherapy (OR: 1.9, CI 95%: 1.1-3.8) and LEV monotherapy (OR: 3.3, CI 95%: 1.5-7.5) were associated with an increased risk of vitamin D deficiency.

The prevalence of vitamin D deficiency is common in children with epilepsy taking VPA or LEV. Hence vitamin D status of children treated with VPA and LEV should be regularly monitored and vitamin D supplements should be considered on an individual basis.