To investigate the degree of endothelial activation and inflammation in prepubertal obese children and to determine the relationship between the markers of endothelial activation, inflammation, and cardiovascular risk factors. In 30 obese and 28 healthy prepubertal children, soluble intercellular adhesion molecule-1 and endothelial leukocyte adhesion molecule-1 (sE-selectin) as markers of endothelial activation and soluble vascular cell adhesion molecule-1 (sVCAM-1) and C-reactive protein (CRP) as markers of endothelial inflammation in addition to cardiovascular risk factors including blood lipids, glucose, insulin, hemoglobin A(1c), and systolic and diastolic blood pressure were investigated and compared. The tests were repeated after an oral glucose tolerance test in the obese group. Fasting CRP levels were found to be significantly higher in obese children. Vascular cell adhesion molecule-1 levels were found to be significantly increased in obese children after oral glucose tolerance test. Fasting CRP was positively correlated with body mass index (BMI) and low-density lipoprotein, whereas sE-selectin was positively correlated with total cholesterol. In the obese group, postload levels of soluble sE-selectin was positively correlated with low-density lipoprotein; sVCAM-1 was positively correlated with insulin and homeostasis model assessment values. Postload soluble intercellular adhesion molecule-1, sVCAM-1, and soluble sE-selectin levels were also positively correlated with each other. In the fasting state, BMI was the significant independent risk factor for CRP, and total cholesterol was the significant risk factor for soluble sE-selectin. Insulin resistance was the significant independent risk factor for postload sVCAM-1, and postload low-density lipoprotein stood as the significant independent risk factor for postload soluble sE-selectin. Endothelial inflammation is present in obese prepubertal children and is mainly associated with insulin resistance and lipid levels as well as BMI. (c) 2005 Elsevier Inc. All rights reserved.