Vitamin D supplementation reduces thyroid peroxidase antibody levels in patients with autoimmune thyroid disease: An open-labeled randomized controlled trial

Sandeep Chaudhary; Deep Dutta; Manoj Kumar; Sudipta Saha; Samim Ali Mondal; Ashok Kumar; Satinath Mukhopadhyay

doi:10.4103/2230-8210.179997

Vitamin D supplementation reduces thyroid peroxidase antibody levels in patients with autoimmune thyroid disease: An open-labeled randomized controlled trial

Indian J Endocrinol Metab. 2016 May-Jun;20(3):391-8. doi: 10.4103/2230-8210.179997.

Authors

Sandeep Chaudhary¹, Deep Dutta², Manoj Kumar¹, Sudipta Saha³, Samim Ali Mondal⁴, Ashok Kumar¹, Satinath Mukhopadhyay¹

Affiliations

¹ Department of Endocrinology and Metabolism, Institute of Post Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
² Department of Endocrinology, Post Graduate Institute of Medical Education and Research, Dr. Ram Manohar Lohia Hospital, New Delhi, India.
³ Department of Radiology, Institute of Post Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.
⁴ Department of Biochemistry, Dr. B C Roy Post Graduate Institute of Basic Medical Education and Research, Institute of Post Graduate Medical Education and Research and Seth Sukhlal Karnani Memorial Hospital, Kolkata, West Bengal, India.

Abstract

Background and aims: Although Vitamin D deficiency has been linked to autoimmune thyroid disorders (AITD), the impact of Vitamin D supplementation on thyroid autoimmunity is not known. This study aimed to evaluate the impact of Vitamin D supplementation on thyroid autoimmunity (thyroid peroxidase antibody [TPO-Ab] titers) in patients with newly diagnosed AITD in a randomized controlled trial.

Materials and methods: One hundred two patients with newly diagnosed AITD (TPO-Ab > 34 kIU/L and/or sonographic evidence of thyroiditis) patients were randomized into Group-1 (intervention group) and Group-2 (control group). Group-1 received cholecalciferol 60,000 IU weekly and calcium 500 mg/day for 8 weeks; Group-2 received calcium 500 mg/day for 8 weeks. Responders were defined as ≥25% fall in TPO-Ab titers. Individuals with at least 3-month follow-up were analyzed. Trial is registered at ctri.nic.in (CTRI/2015/04/005713).

Results: Data from 100 AITD patients (68 with thyroid stimulating hormone [TSH] ≤10 mIU/L, 32 with TSH > 10 mIU/L), 93% having Vitamin D insufficiency, were analyzed. TPO-Ab titers were highest among patients in the lowest 25-hydroxyvitamin D quartile (P = 0.084). At 3 months follow-up, there was significant fall in TPO-Ab in Group-1 (-46.73%) as compared to Group-2 (-16.6%) (P = 0.028). Sixty-eight percentage patients in Group-1 were responders compared to 44% in Group-2 (P = 0.015). Kaplan-Meier analysis revealed significantly higher response rate in Group-1 (P = 0.012). Significantly greater reduction in TPO-Ab titers was observed in AITD with TSH ≤ 10 mIU/L compared to TSH > 10 mIU/L. Cox regression revealed Group-1 followed by TPO-Ab and free tetraiodothyronine levels to be a good predictor of response to therapy (P = 0.042, 0.069, and 0.074, respectively).

Conclusion: Vitamin D supplementation in AITD may have a beneficial effect on autoimmunity as evidence by significant reductions in TPO-Ab titers.

Keywords: Autoimmune hypothyroidism; Vitamin D; autoimmunity; thyroid peroxidase antibody; thyroiditis.