Overweight and Hyperinsulinemia Provide Individual Contributions to Compromises in Brachial Artery Distensibility in Healthy Adolescents and Young Adults: Brachial Distensibility in Children.

Cincinnati Children's Hospital Medical Center Division of Preventive Cardiology.
Journal of the American Society of Hypertension (Impact Factor: 2.68). 07/2007; 1(3):200-207. DOI: 10.1016/j.jash.2007.01.008
Source: PubMed

ABSTRACT BACKGROUND: Brachial artery distensibility (BrachD) was measured in healthy children to identify associations with atherosclerotic risk factors. METHODS: 969 black and white subjects 13-22 years were classified as lean (L) or overweight (O) and hyperinsulinemic (H-I) or normoinsulinemic (N-I). BP and BrachD were obtained with a DynaPulse Pathway instrument. ANOVA was performed looking for group mean differences. Correlations between BrachD and risk variables were examined. Determinates of BrachD were determined by backward elimination regression stratified by BMI-Insulin group. RESULTS: Decreased BrachD correlated with male gender, O, higher BP, HR, fasting glucose and log of fasting insulin after adjusting for pulse pressure (PP). BrachD was greatest in L/N-I with progressive decreases seen in L/H-I, O/N-I, and O/H-I subjects. Regression modeling found PP and HR were major determinates of BrachD. Glucose was significant for subjects with N-I regardless of adiposity. Excluding BP, glucose remained important in N-I subjects. Gender was significant for all. HR retained significance only in O subjects regardless of insulin level. CONCLUSIONS: In healthy adolescents, hyperinsulinemia and obesity adversely affect brachial artery function with overweight contributing to a greater degree. In normoinsulinemic subjects, fasting glucose was inversely related to BrachD. Metabolic factors may play a role in vascular function in youth.

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