Thyroid hormones regulate body composition and metabolism, and associations between T3 hormone and cardiometabolic function have been extensively studied in adults. In contrast, these associations have been little investigated in children.

A study published in the journal Frontiers Endocrinology and led by Dr. Abel López-Bermejo, head of the Obesity and Cardiovascular Risk in Paediatrics group at IDIBGI and paediatrician at the Trueta Hospital in Girona, has examined whether serum free T3 hormone (T3ll) is associated with cardiometabolic parameters in apparently healthy school-age children with normal thyroid function in the counties of Girona. Specifically, a first observation was made at the beginning of the study (~8 years of age) and a second follow-up observation 4 years later (~12 years of age).

As results, an association was observed between serum T3ll levels and various cardiometabolic parameters, such as body mass index, waist circumference, blood pressure, insulin function and blood triglyceride levels. These associations were observed both at baseline, when the children were 8 years old, and at follow-up four years later, predicting changes in the same parameters that had been analysed. These associations were more pronounced in children with higher TSH levels, higher cardiometabolic risk and higher T3ll levels.

The research team of the article, whose first author is Dr. Gemma Carreras-Badosa, post-doctoral researcher of the same group, concludes that serum T3ll is related to and has a predictive value on several cardiometabolic parameters in apparently healthy school-age children with normal thyroid function. These results can be explained as a regulatory response of the organism through which the increase in T3ll enhances the normalisation of cardiometabolic risk parameters in children.

Reference article: Carreras-Badosa G, Puerto-Carranza E, Mas-Parés B, Gómez-Vilarrubla A, Cebrià-Fondevila H, Díaz-Roldán F, Riera-Pérez E, de Zegher F, Ibañez L, Bassols J and López-Bermejo A (2023) Circulating free T3 associates longitudinally with cardio-metabolic risk factors in euthyroid children with higher TSH. Front. Endocrinol. 14:1172720.

DOI: 10.3389/fendo.2023.1172720