title: Subclinical hypothyroidism during valproic acid therapy in children and adolescents with epilepsy.
abstract: The aim of this study was to evaluate the incidence of thyroid dysfunction during valproic acid (VPA) therapy in children and adolescents with epilepsy. The serum levels of thyroid-stimulating hormone (TSH), free thyroxine, and triiodothyronine were evaluated in 61 children with epilepsy who received VPA monotherapy for more than 6 months and in 144 controls. We analyzed the effect of age, seizure type, duration of VPA treatment, dose of VPA, and serum level of VPA on thyroid function. The incidence of subclinical hypothyroidism was significantly higher in patients with VPA therapy than in controls (52.4 vs. 16.7%; p < 0.001). In addition, of the 61 patients, 5 (8.1%) exhibited TSH levels that were >10 μIU/mL. However, none of the patients and controls showed overt hypothyroidism. Serum VPA level and daily dose of VPA were correlated with TSH level. Subclinical hypothyroidism developed frequently in children and adolescents during VPA therapy.
authors.affiliation: Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University, College of Medicine, Seoul, Republic of Korea.
authors.forename: Se Hee
authors.initials: SH
authors.lastname: Kim
authors.forename: Hye Rim
authors.initials: HR
authors.lastname: Chung
authors.forename: Seung Hyo
authors.initials: SH
authors.lastname: Kim
authors.forename: Hunmin
authors.initials: H
authors.lastname: Kim
authors.forename: Byung Chan
authors.initials: BC
authors.lastname: Lim
authors.forename: Jong Hee
authors.initials: JH
authors.lastname: Chae
authors.forename: Ki Joong
authors.initials: KJ
authors.lastname: Kim
authors.forename: Yong Seung
authors.initials: YS
authors.lastname: Hwang
authors.forename: Hee
authors.initials: H
authors.lastname: Hwang
mesh_terms: D000293:Adolescent; D000927:Anticonvulsants / Q000009:adverse effects* / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000097:blood / Q000188:drug therapy*; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000139:chemically induced*; D012720:Severity of Illness Index; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000187:drug effects; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D014635:Valproic Acid / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D000927:Anticonvulsants; D014284:Triiodothyronine; D014635:Valproic Acid; D013972:Thyrotropin; D013974:Thyroxine