Association of thyroid function, within the euthyroid range, with cardiovascular risk: The EPIPorto study

Abstract

BackgroundThyroid hormones are important modulators of cardiovascular function. Both hypothyroidism and hyperthyroidism are known to contribute to an increased cardiovascular risk. It remains uncertain whether thyroid hormones level within the euthyroid range are associated with cardiometabolic risk. We aimed to evaluate the association between thyroid function levels within the euthyroid range and cardiovascular risk in a population-based cohort.MethodsEight hundred thirty-five subjects aged ≥45 years from the EPIPorto population-based cohort were included. We excluded participants with TSH, free T4 (FT4), or free T3 (FT3) outside of the reference range, or with previous cardiovascular or thyroid disease. The associations between thyroid function, cardiovascular risk factors and the 10-year estimated risk of cardiovascular events (using SCORE2 and SCORE2-OP) were evaluated in linear and logistic regression models, crudely and adjusting for age, sex, BMI, diabetes, and smoking.ResultsThe mean age of the participants was 61.5 (SD 10.5) years and 38.9% were men. Eleven percent of the participants had diabetes, 47.8% had dyslipidemia, and 54.8% had hypertension. The mean body mass index (BMI) was 27.4 (SD 4.6) kg/m2, and the median (percentile25-75) 10-year risk of cardiovascular events was 5.46% (2.92, 10.11). Participants with higher BMI, larger waist circumference and higher hs-CRP had higher levels of FT3 and FT3/FT4 ratio. Lower FT3/FT4 ratio and higher FT4 levels were associated with higher prevalence of diabetes and more adverse lipid profile. Higher TSH, lower FT3 and lower FT3/FT4 ratio were associated with lower eGFR. Lower FT3, lower FT3/FT4 ratio and higher FT4 were associated with an increased 10-year risk of cardiovascular events.ConclusionsIn a population-based study, variations of thyroid function within the euthyroid range were associated with cardiovascular risk factors. On one hand, individuals with higher BMI, larger waist circumference and higher hs-CRP had higher levels of FT3 and FT3/FT4 ratio. On the other hand, a decreased conversion of T4 to T3 (lower FT3, lower FT3/FT4 ratio and/or higher FT4) was associated with a higher prevalence of diabetes, a more adverse lipid profile, a lower eGFR and an increased 10-year risk of cardiovascular events.

Interaction between triglyceride-glucose index and thyroid hormones on coronary artery disease risk in patient with euthyroid

“…Patients with CAD often have thyroid dysfunction. Previous studies have found that low FT3 levels were negatively correlated with CAD and major adverse cardiovascular events ( 28 ). The TyG index has been studied as an alternative indicator of IR in many fields.…”

Description of the Metabolic Syndrome and Its Individualized Risk in a Latin American Cohort of Geriatric Patients With Hypothyroidism

“…The time of diagnosis of hypothyroidism was 11.8 + 5.6 years. The presence of abdominal circumference was the main criterion of metabolic syndrome, followed by high total cholesterol and in third place, high body mass index levels; these metabolic alterations have been found in the population with hypothyroidism internationally (16). These values are worrisome since they indicate a high prevalence of metabolic syndrome criteria in this particular population cohort.…”