The association of thyroid hormones and blood pressure in euthyroid preadolescents

Abstract

Background: Hypertension is the leading cause of cardiovascular disease worldwide, and both high and low blood pressures are associated with various chronic diseases. Thyroid hormones have profound effects on cardiovascular function, including on blood pressure. Recent studies have shown that childhood hypertension can lead to adult hypertension. Therefore, adequate blood pressure control is important from early life. Employing a life-course approach, we aimed to investigate the association between thyroid hormones and blood pressure in children. Methods: A total of 290 children from the Ewha Woman's University Hospital birth cohort participated in a preadolescent check-up program. We assessed the levels of serum thyroid-stimulating hormone (TSH) and free thyroxine (FT4) and the blood pressure status in these children. Thyroid hormone concentrations were measured using an electro-chemiluminescence immunoassay (ECLIA), and hypertension was defined according to the guideline of the Korea Centers for Disease Control and Prevention. Results: The sex-, age-, and height-adjusted prevalence of hypertension was 27.0% in the present study. On regression analysis, serum FT4 showed significantly negative association with diastolic blood pressure (DBP; β=-8.24, 95% CI: -14.19-2.28, p=0.007). However, these relationships were not significant after adjustment for sex, age, and current body mass index. The levels of serum TSH showed no relationship with mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) after adjustment. No significant differences in serum TSH and FT4 levels according to hypertension status were found. Conclusions: These findings suggest that thyroid hormone is not independently associated with increased blood pressure in euthyroid preadolescents. © 2016 by De Gruyter.