The effects of topiramate and valproate therapy on insulin, c-peptide, leptin, neuropeptide Y, adiponectin, visfatin, and resistin levels in children with epilepsy.

Purpose: Antiepileptic drugs may affect the endocrine system. We investigated the effects of valproic acid and topiramate on the levels of insulin, c-peptide and adipocytokines in pre-pubertal patients with idiopathic partial and generalized epilepsy.

Methods: Forty-one children with epilepsy were included. The patients were divided into two groups (valproic acid; n = 21, topiramate; n = 20). The weight, height, body mass index and homeostasis model assessment of insulin resistance (HOMA-IR) were recorded and insulin, c-peptide, leptin, neuropeptide Y, adiponectin, visfatin and resistin levels were determined at 0, 6 and 12 months of therapy.

Results: In the valproate group, weight and height increased significantly. Seven of 21 patients were overweight at the end of one year. Leptin was higher in the overweight subgroup. Although insulin and HOMA-IR increased (p < 0.05), none of the patients showed hyperinsulinism or IR. Resistin had decreased at the 6th and 12th months (p < 0.05). In the topiramate group, some statistically nonsignificant changes were demonstrated.

Conclusion: The mechanisms behind valproate and topiramate-related weight control are still unclear, especially in children. Valproate and topiramate affect the weight, BMI, and insulin, leptin and adipocytokine levels in prepubertal children. We suggest that further studies including more patients with a long follow-up period are necessary to draw a firm conclusion regarding an association between the treatment with these drugs and the levels of leptin, insulin and adipocytokines.