title: Influence of solar irradiation on vitamin D levels in children on anticonvulsant drugs.
abstract: Previous studies about the serum levels of vitamin D metabolites in epileptic patients have given conflicting results. We have investigated the influence of chronic anti-epileptic treatment on mineral metabolism in 17 ambulatory epileptic children who were studied for 2 seasons with high and low levels of solar radiation, respectively. No differences in serum calcium, phosphate or 1.25-dihydroxyvitamin D were observed between patients and control children. Patients also had normal levels of 25-hydroxyvitamin D [25(OH)D] in summer. However, serum 25(OH)D concentrations were lower in patients than in controls in winter months (12.6 +/- 1.4 versus 19.6 +/- 1.2 ng/ml, P less than 0.001). These findings point out the influence of the intensity of solar irradiation, and subsequently of vitamin D availability, on the effect of anticonvulsant drugs on vitamin D metabolism, and may help to explain the conflicting results of previous reports. Prophylactic vitamin D therapy should be considered when climatic conditions or patients' life styles do not allow an adequate exposure to sunlight.
authors.affiliation: Department of Internal Medicine, Hospital Marques de Valdecilla, School of Medicine, Santander, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Riancho
authors.forename: C
authors.initials: C
authors.lastname: del Arco
authors.forename: R
authors.initials: R
authors.lastname: Arteaga
authors.forename: J L
authors.initials: JL
authors.lastname: Herranz
authors.forename: M
authors.initials: M
authors.lastname: Albajar
authors.forename: J G
authors.initials: JG
authors.lastname: Macias
mesh_terms: D000293:Adolescent; D000927:Anticonvulsants / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000188:drug therapy / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D012621:Seasons; D014807:Vitamin D / Q000097:blood / Q000528:radiation effects*
chemical_list: D000927:Anticonvulsants; D014807:Vitamin D