Childhood Obesity And Carotid Artery Intima - Media Thickness And Arterial Endothelial Function

Background. Endothelial dysfunction (measured as reduced flow-mediated dilatation, FMD) and thickening of the arterial intima-media layer (IMT) are early indicator of atherosclerosis in adults and can also be demonstrated in children suffering from diabetes and genetic disorders of lipid metabolism. There is a paucity of data, however, on whether early atherosclerotic alterations can be induced and promoted by childhood obesity. As the increasing prevalence of obesity in children is an important public health issue in China and abroad, we studied ultrasonographic signs of early artherosclerosis in relation to established risk factors of cardiovascular disease in a group of obese Chinese children, compared with control.Materials and Methods. Forty-three patients with pure childhood obesity (body weight exceeding > 20% standard body weight or body mass index > 24) were compared to a group of 28 healthy controls. Both groups did not show significant differences in age, gender ratio and body height. IMT, FMD, carotid hemodynamic parameters and biochemical markers of dyslipidemia were measured and analysed in relation to subject characteristics. Predictors of increased IMT and reduced FMD were identified with multifactor linear regression.Results. Obese children showed significantly higher systolic and diastolic blood pressure and elevated levels of total cholesterol, LDL cholesterol, triglycerides and Apolipoprotein B. Carotid IMT was significantly increased (0.62 mm vs. 0.46 mm, p<0.001) and flow-mediated dilatation was markedly reduced (10.9% vs. 18.8%, p<0.001) in the obesity group, compared with control. Statistical significance persisted after adjustment of IMT and FMD for body mass index (BMI) on ANCOVA. On stepwise linear regression, BMI was found to be the strongest predictor of increased IMT and reduced FMD, while body weight, blood pressure, total cholesterol, LDL cholesterol and Apo B were also positively correlated (all p < 0.01). Bilateral IMT measurements in the common carotid artery and in the internal carotid artery of obese subjects all showed significantly increased IMT with a high correlation of all measurements suggesting that intima-media thickening is a systemic process involvingthe whole of the carotid vascular bed and possibly other large arteries, including the coronary arteries, as well.Conclusions. Marked signs of early atherosclerosis were found in obese school children. Childhood obesity can be considered to contribute to the development and the progression of early atherosclerosis, particularly in combination with hypertension and dyslipidaemia. In order to prevent coronary atherosclerosis and other cardiovascular diseases, it is vital to control obesity starting from childhood. Ultrasonography may be used to identify high risk patients among severely obese children.