Duration of valproic acid monotherapy correlates with subclinical thyroid dysfunction in children with epilepsy.

Journal: Epileptic Disorders : International Epilepsy Journal With Videotape
Published:
Abstract

To identify potential risk factors for the development of subclinical hypothyroidism following long-term valproic acid monotherapy in children with epilepsy. Serum levels of thyroid-stimulating hormone, free thyroxine, free triiodothyronine, thyreoglobulin antibodies, and thyroid peroxidase antibodies were determined in 41 patients and in 41 sex- and age-matched healthy children. Mean valproic acid treatment duration was 2.80±1.96 years. The valproic acid group had higher serum thyroid-stimulating hormone (p<0.001) and free triiodothyronine (p<0.05) levels compared to the control group. Serum thyroid-stimulating hormone and free triiodothyronine were above the upper limit for healthy controls in 34% and 32% of patients, respectively, and no clinical features of thyroid dysfunction were observed. Duration of valproic acid monotherapy for less than four years was a risk factor for elevated thyroid-stimulating hormone levels. One third of children with normal range serum valproic acid levels may have elevated serum thyroid-stimulating hormone and free triiodothyronine levels, especially in the first four years of treatment.

Authors
Violeta Ilić, Dragana Bogićević, Branislava Miljković, Maja Ješić, Marijana Kovačević, Milica Prostran, Sandra Kovačević
Relevant Conditions

Hypothyroidism, Epilepsy