Novel Clinical Evidence of an Association between Homocysteine and Insulin Resistance in Patients with Hypothyroidism or Subclinical Hypothyroidism

PLoS One. 2015 May 4;10(5):e0125922. doi: 10.1371/journal.pone.0125922. eCollection 2015.

Abstract

Objective: Hypothyroidism (HO) can induce significant metabolic dysfunction and increase cardiovascular disease risk. In the present study, we investigated the relationship between homocysteine (Hcy) and insulin resistance (IR) in patients with HO or subclinical hypothyroidism (SHO).

Methods: A total of 270 subjects were enrolled. All subjects were divided into the following three groups: HO, SHO and control. Plasma levels of Hcy were measured, and each patient's homeostatic index of insulin resistance (HOMA-IR) was calculated. Statistical analyses were carried out to evaluate the correlations among groups and to determine the predictors of IR in patients with HO or SHO.

Results: The HOMA-IR value was significantly higher in the HO group than in the SHO and control groups. Plasma levels of Hcy were markedly increased in the HO group compared with those of the SHO group and controls. In addition, plasma levels of Hcy were positively correlated with the HOMA-IR values in both the HO and SHO groups. Multiple linear regression models showed that plasma levels of Hcy and free thyroxine (FT4) were the only predictors of HOMA-IR in patients with HO or SHO.

Conclusions: Plasma levels of Hcy and HOMA-IR were increased in patients with HO or SHO. Our results suggest that HO and SHO may increase the risk for atherogenesis and cardiovascular disease by increased IR. The increased IR induced by hyperhomocysteinemia in patients with HO or SHO may partially explain this adverse effect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Case-Control Studies
  • Fasting
  • Female
  • Glycated Hemoglobin
  • Homocysteine / blood*
  • Humans
  • Hypothyroidism / blood
  • Hypothyroidism / diagnosis
  • Hypothyroidism / metabolism*
  • Insulin Resistance*
  • Lipids / blood
  • Male
  • Middle Aged
  • Risk Factors
  • Thyroid Function Tests

Substances

  • Glycated Hemoglobin A
  • Lipids
  • Homocysteine

Associated data

  • Dryad/10.5061/dryad.6H1S2

Grants and funding

Our work was supported by grants from the Major National Basic Research Program of China (No. 2011CB503904), the Beijing Natural Science Foundation (N0.7142060) and the Chinese National Natural Science Foundation (No. 81270369, 81070244) to Guang Wang. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.