The prevalence of obesity in children is increasing rapidly. Epidemiologic studies suggest that obesity induced atherosclerosis may start in childhood. We investigated whether obese children show early abnormalities of the arterial wall and endothelial dysfunction.

Thirty-eight obese children(14-16 years old of age, male, body mass index 29.40±3.18 kg/m²) and forty-five age and sex-matched healthy control children(body mass index 18.43±1.01 kg/ m²) were enrolled. Their carotid artery intima-media thickness(IMT) and brachial artery flowmediated dilation(FMD) response were measured by high-quality ultrasound system, and compliance, distensibility, stiffness index, incremental elastic modulus and wall stress were calculated by equation. In addition, we looked at the relations between these arterial features and metabolic cardiovascular risk factors.

The obese children had significantly increased IMT(0.52±0.09 mm vs 0.40±0.07 mm, P < 0.001) and markedly impaired FMD(7.35±7.78 percent vs 20.34±16.81 percent, P <0.001) than the healthy controls. But the compliance and distensibility were lower, and the stiffness index, incremental elastic modules and wall stress were higher in the obese group than the control group, but not statistically significantly. Body mass index was highly associated with increased IMT(r=0.612, P < 0.001) and reduced FMD(r=-0.414, P <0.001).

We showed the deleterious effect of child obesity on both early functional and structural atherosclerotic markers. The ultrasonic findings will be used for screening and follow up markers to identify high-risk patients among obese children.