Vitamin D levels in children and adolescents with antiepileptic drug treatment

Purpose: This study was to evaluate the relationship of 25(OH)D₃ levels with anticonvulsant use and other possible factors in epileptic children and adolescents. Materials and Methods: We studied 143 patients with epilepsy (90 boys, 53 girls; 11.21±4.49 years), who had been treated with anticonvulsants for more than 1 year. Patients who had taken multiple vitamins before the blood test and those who have the limitation of physical activity (wheelchair-bound) were excluded from the study. We evaluated the difference in vitamin D status according to the type and number of anticonvulsants taken and other factors such as gender, age, intelligence and seizure variables. Results: For patients with mental retardation or developmental delay, 25(OH)D3 levels were lower than the levels in patients with normal intelligence quotient levels (p=0.03). 25(OH)D3 levels were lower in patients who had taken anticonvulsants for more than 2 years as compared to those who had taken them for less than 2 years (p=0.03). Those taking oxcarbazepine had significantly lower vitamin D levels than patients taking valproic acid (p=0.01). However, no effects of number of anticonvulsants taken were detectable. More than two-thirds of the patients were diagnosed with osteopenia or osteoporosis in patients showing either vitamin D insufficiency or deficiency. Conclusion: The possibility of vitamin D deficiency can be considered in pediatric patients taking anticonvulsants if they have mental retardation or developmental delay or if they have been taking anticonvulsants for more than 2 years or taking hepatic enzyme inducing drugs.