Low thyroid hormone status as a cardiovascular risk factor: A cross-sectional study from NHANES 2007-2012

Area of Science:

• Endocrinology
• Cardiovascular Medicine
• Epidemiology

Background:

• The association between thyroid hormone levels and ischemic heart disease (IHD) is not fully understood.
• Thyroid dysfunction can impact cardiovascular health, but specific hormone levels' role in IHD requires further investigation.

Purpose of the Study:

• To investigate the relationship between serum free triiodothyronine (FT3) and total triiodothyronine (TT3) levels and the prevalence of ischemic heart disease (IHD) in a US adult population.
• To explore potential nonlinear dose-response relationships between thyroid hormones and IHD.

Main Methods:

• Cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) 2007-2012.
• Included 1864 participants; IHD defined by self-report of physician-diagnosed coronary heart disease, angina, or myocardial infarction.
• Multivariable logistic regression and restricted cubic spline modeling were used to analyze associations, adjusting for confounders.

Main Results:

• Participants with IHD had significantly lower serum FT3 and TT3 levels compared to those without IHD.
• Higher FT3 and TT3 levels were independently associated with reduced odds of IHD, with significant inverse relationships observed across quartiles.
• Restricted cubic spline analysis indicated significant nonlinear dose-response relationships for both FT3 and TT3 with IHD risk.

Conclusions:

• Serum FT3 and TT3 levels are inversely associated with ischemic heart disease in the US population.
• Thyroid hormone levels, particularly FT3 and TT3, may serve as potential biomarkers for cardiovascular risk assessment.
• These findings suggest thyroid hormone status could be a therapeutic target for IHD prevention.