Exp Clin Endocrinol Diabetes 2017; 125(04): 229-233
DOI: 10.1055/s-0042-123038
Article
© Georg Thieme Verlag KG Stuttgart · New York

The Effect of Vitamin D on Thyroid Autoimmunity in Levothyroxine-Treated Women with Hashimoto’s Thyroiditis and Normal Vitamin D Status

Authors

  • Robert Krysiak

    1   Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Katowice, Poland
  • Witold Szkróbka

    1   Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Katowice, Poland
  • Bogusław Okopień

    1   Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Katowice, Poland
Further Information

Publication History

received 30 August 2016
first decision 14 November 2016

accepted 02 December 2016

Publication Date:
10 January 2017 (online)

Abstract

Background: Low vitamin D status is associated with autoimmune thyroid disease. Oral vitamin D supplementation was found to reduce titers of thyroid antibodies in levothyroxine-treated women with postpartum thyroiditis and low vitamin D status.

Methods: The study included 34 women with Hashimoto’s thyroiditis and normal vitamin D status (serum 25-hydroxyvitamin D levels above 30 ng/mL) who had been treated for at least 6 months with levothyroxine. On the basis of patient preference, women were divided into 2 groups, receiving (n=18) or not receiving (n=16) oral vitamin D preparations (2000 IU daily). Serum levels of thyrotropin, free thyroxine, free triiodothyronine and 25-hydroxyvitamin D, as well as titers of thyroid peroxidase and thyroglobulin antibodies were measured at the beginning of the study and 6 months later.

Results: There were no significant differences in baseline values between both study groups. 25-hydroxyvitamin D levels inversely correlated with titers of thyroid antibodies. No changes in hypothalamic-pituitary-thyroid axis activity and thyroid antibody titers were observed in vitamin-naïve patients. Vitamin D increased serum levels of 25-hydroxyvitamin D, as well as reduced titers of thyroid antibodies. This effect was more pronounced for thyroid peroxidase than for thyroglobulin antibodies and correlated with their baseline titers.

Conclusions: Vitamin D preparations may reduce thyroid autoimmunity in levothyroxine-treated women with Hashimoto’s thyroiditis and normal vitamin D status.