ESPE Abstracts

Background: Moderately elevated thyroid-stimulating hormone (TSH) with normal serum concentrations of free thyroxine (fT4), suggesting subclinical hypothyroidism, is the most common hormonal abnormality in obese children. Controversy remains whether thyroid dysfunction related to obesity has an influence on the cardiovascular risk factors.

Objective and hypotheses: The aim of the study was to assess correlation between TSH and fT4 and chosen atherogenic risk factors in obese children and adolescent.

Method: The study group consisted of 110 obese children, aged 5 −18 years (11.54±2.9 years) and 38 healthy children (13.4±2.63 years). Obesity was defined using IOTF criteria. In each patient anthropometric measurements, blood samples (TSH, fT4, lipids profile, adiponectin) and carotid intima – media thickness (IMT) were taken. The resulting data was used to calculate indicators of atherogenesis: TC/HDL-C, TG/HDL-C, LDL-C/HDL-C.

Results: Obese children had higher mean serum TSH levels compared to their lean peers (2.1±1.0 μIU/ml vs 1.5±0.6 μIU/ml, P=0.000) and an adverse atherogenic lipid profile. Serum fT4 concentrations were comparable between groups. Serum TSH values correlated with TC/ HDL-C (r=0.286, P=0.000), TG/ HDL-C (r=0.236, P=0.004), LDL-C/ HDL-C (r=0.281, P=0.001) and IMT (r=0.02, P=0.003), but not with adiponectin. In multivariate regression analysis TSH weakly correlated only with IMT after adjustment for age, gender and BMI (β=0.249, P=0.04). This relationship weakened after considering lipid profile (β=0.242, P=0.058). No relationship was found for fT4.

Conclusion: Elevated level of TSH in obese children did not seem to impact atherogenic lipid indicators and carotid IMT. Therefore, adverse lipid profile should still be considered the main risk factor for development of cardiovascular disease in obese children.