Endocrine Abstracts

Background: Over the past decade, numerous non-skeletal diseases have been reported to be associated with vitamin D deficiency including autoimmune thyroid pathology.

Aim: The aim of the study is to evaluate the effects of vitamin D supplementation on insulin resistance in hypothyroidism.

Materials and methods: Forty-seven participants, 32–74 years old, including 39 women (82.9%) and 8 men (17.1%) took part in the study. Serum TSH, insulin and 25(OH)D concentration were measured, and HOMA-IR was calculated. All measurements were performed at the beginning and the end of the study. Patients with hypothyroidism received 21,000 unit of cholecalciferol orally per week for 12 weeks. The results were analyzed by descriptive tests, and a comparison between variables were made using paired T-tests or Wilcoxon tests, as a appropriate.

Results: All of the participants were vitamin D deficient. Mean serum 25(OH)D concentration was 21.72±6.14 ng/ml. The results at baseline and at the end were for insulin 19.36±2.39 and 9.92±2.38 mIU/l (P<0.05) and for HOMA-IR, 3.91±0.32 and 2.38±0.17 (P<0.05) respectively.

Conclusions: Our data showed significant improvement in serum insulin and in HOMA-IR after treatment with cholecalciferol, suggested that vitamin D supplementation could reduce insulin resistance in hypothyroidism.