Associations of thyroid feedback quantile-based index with diabetes in euthyroid adults in the United States and China

Abstract

Background: We aimed to investigate the associations between thyroid hormone sensitivity indices and diabetes in euthyroid adults in the United States and China.

Methods: 2296 euthyroid adults from the NHANES in the United States and 8319 euthyroid adults from the SPEED-Shunde in China were involved. The thyroid sensitivity indices, namely TFQIFT4 and TFQIFT3, were calculated. Multivariable logistic regression, restricted cubic spline analysis, and general ordinal logit regression were utilized.

Results: In the NHANES, compared with participants in quartile 1st (Q1), those in Q4 of TFQI_FT3 (OR 2.12, 95% CI (1.18, 3.81)) and those in Q3 of TFQI_FT4 (OR 2.31, 95% CI (1.18, 4.53)) (both P _{for trend} < 0.05) were associated with a greater prevalence of diabetes. In the SPEED-Shunde, compared with participants in Q1, those in Q4 of TFQI_FT3 had a greater prevalence of diabetes (OR 1.36, 95% CI (1.11, 1.66) (P _{for trend} < 0.05), while no significant associations between TFQI_FT4 and diabetes were found.

Conclusions: TFQI_FT3 was associated with a higher prevalence of diabetes both in the United States and China. However, TFQI_FT4 was only associated with a higher prevalence of diabetes in the United States, not in China. Further prospective cohort studies are necessary to validate these findings.

Keywords: Impaired sensitivity to thyroid hormones; TFQI; diabetes.