Vitamin D deficiency and its association with thyroid peroxidase antibodies positive hypothyroidism - Experience in a tertiary center in South India

Introduction: Vitamin D deficiency is one of the major health problems globally, and the role of Vitamin D as an immunomodulator has been recently emphasized. There is increasing evidence to suggest that Vitamin D plays a significant role in reducing the incidence of autoimmune diseases. However, at present, its role in autoimmune thyroid disease is not conclusive. Hence, in our study, we aimed to examine the relationship between thyroid peroxidase antibodies (TPOAbs) and Vitamin D deficiency in the hypothyroid patient. Subjects and Methods: One hundred and four known hypothyroid patients not on Vitamin D supplementation were included in the study. They were divided into two groups with TPOAb positive and TPOAb negative, and serum 25(OH) Vitamin D3 (25[OH] D3) was measured and compared in two groups. Thyroid hormones (TSH and T4) were also evaluated in all patients. Results: Serum 25(OH)D3 was significantly lower in TPOAb-positive patients than in TPOAb-negative patients with P = 0.038. Mean serum TSH was significantly high in TPOAb-positive hypothyroid patients than in TPOAb-negative patients with P = 0.047. Conclusion: Our study shows that patients with TPOAb positivity have more significant 25(OH)D3 deficiency and uncontrolled hypothyroidism. Our study encourages the advisability of screening for Vitamin D deficiency for all hypothyroid patients and 25(OH)D3 supplementation.