Association between Abdominal Fat Distribution and Free Triiodothyronine in a Euthyroid Population

Obes Facts. 2020;13(3):358-366. doi: 10.1159/000507709. Epub 2020 Jun 5.

Abstract

Background: Obesity is closely related to thyroid hormones; however, the relationship between abdominal fat distribution and thyroid hormones has rarely been explored.

Objectives: This study aimed to explore the relationship between abdominal fat distribution and free triiodothyronine (FT3) and FT3 to free thyroxine (FT4) ratio (FT3/FT4) in a euthyroid population.

Methods: The present study enrolled 1,036 participants (age range 27-81 years; 445 men and 591 women). The visceral fat area (VFA) and the subcutaneous fat area (SFA) were determined by magnetic resonance imaging. FT3, FT4, and thyroid-stimulating hormone were measured by an electrochemical luminescence immunoassay.

Results: In both men and women, SFA increased according to the increase of FT3 and FT3/FT4 tertiles (p for trend <0.05), while VFA did not significantly change. In the multivariate stepwise regression analysis, SFA was independently and positively related to FT3 in both men and women, the standardized β (95% CI) were 0.183 (0.094, 0.272) (p < 0.001) and 0.089 (0.007, 0.171) (p = 0.033), respectively. Moreover, SFA was independently and positively related to FT3/FT4 in men, the standardized β (95% CI) was 0.196 (0.101, 0.290) (p < 0.001). However, VFA was not related to either FT3 or FT3/FT4 in both genders.

Conclusions: Abdominal subcutaneous fat was independently related to increased FT3 in a euthyroid population.

Keywords: Free triiodothyronine; Free triiodothyronine to free thyroxine ratio; Subcutaneous fat area; Visceral fat area.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abdominal Fat / chemistry
  • Abdominal Fat / metabolism*
  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Goiter, Nodular / metabolism
  • Humans
  • Male
  • Middle Aged
  • Obesity
  • Triiodothyronine / analysis
  • Triiodothyronine / metabolism*

Substances

  • Triiodothyronine

Supplementary concepts

  • Euthyroid Goiter