The effect of vitamin D supplementation on insulin resistance and arterial stiffness in patients with hypothyroidism
Main Article Content
Abstract
Background. Recent epidemiological studies revealed a significant inverse relationship between vitamin D levels, insulin resistance (IR), and cardiovascular diseases. However, few interventional studies have evaluated the effect of vitamin D supplementation on cardiovascular risk, such as IR and arterial stiffness in hypothyroidism. The purpose of the study is to investigate the role of vitamin D supplementation on cardiovascular risk in patients with hypothyroidism, including metabolic parameters, IR, and arterial stiffness. Materials and methods. We enrolled 55 patients with hypothyroidism who were taking levothyroxine medications. We excluded patients who were taking vitamin D or calcium supplements. Participants were randomized into the vitamin D group (cholecalciferol 4,000 IU/day, n = 30) or the control group (only levothyroxine, n = 25). We compared their IR (homeostatic model assessment (HOMA-IR)) and arterial stiffness (brachial-ankle pulse wave velocity) before and after 12 weeks of intervention. Results. The baseline characteristics of the two groups were similar. A total of 55 participants completed the study protocol. At the end of the study period, 25-hydroxyvitamin D (25(OH)D) levels were significantly higher in the vitamin D group than in the control group (32.7 ± 7.2 ng/ml vs. 17.1 ± 6.3 ng/ml, p < 0.05). There was no difference in HOMA-IR or changes in arterial stiffness between the groups. Conclusions. Our data suggest that vitamin D supplementation might be effective in terms of elevating 25(OH)D levels. However, we identified no beneficial effects on cardiovascular risk in hypothyroidism, including IR and arterial stiffness.
Article Details

This work is licensed under a Creative Commons Attribution 4.0 International License.
Our edition uses the copyright terms of Creative Commons for open access journals.
Authors, who are published in this journal, agree with the following terms:
- The authors retain rights for authorship of their article and grant to the edition the right of first publication of the article on a Creative Commons Attribution 4.0 International License, which allows others to freely distribute the published article, with the obligatory reference to the authors of original works and original publication in this journal.
- Directing the article for the publication to the editorial board (publisher), the author agrees with transmitting of rights for the protection and using the article, including parts of the article, which are protected by the copyrights, such as the author’s photo, pictures, charts, tables, etc., including the reproduction in the media and the Internet; for distributing; for the translation of the manuscript in all languages; for export and import of the publications copies of the writers’ article to spread, bringing to the general information.
- The rights mentioned above authors transfer to the edition (publisher) for the unlimited period of validity and on the territory of all countries of the world.
- The authors guarantee that they have exclusive rights for using of the article, which they have sent to the edition (publisher). The edition (the publisher) is not responsible for the violation of given guarantees by the authors to the third parties.
- The authors have the right to conclude separate supplement agreements that relate to non-exclusive distribution of their article in the form in which it had been published in the journal (for example, to upload the work to the online storage of the journal or publish it as part of a monograph), provided that the reference to the first publication of the work in this journal is included.
- The policy of the journal permits and encourages the publication of the article in the Internet (in institutional repository or on a personal website) by the authors, because it contributes to productive scientific discussion and a positive effect on efficiency and dynamics of the citation of the article.
References