Abstract 12668: Obesity-Related Vascular Functional Change is Associated with Insulin Resistance in Children
Background: Insulin resistance has been implicated in the mechanism of vascular dysfunction in adulthood obesity. However, few studies have examined insulin resistance and cardiovascular function in overweight/obese children. The purpose of this study is to assess the relationship between vascular function and cardiovascular risk factors in children.
Methods: Echocardiography was performed in 161 children aged 7 to 15 years (BMI 18 to 34 kg/m2). Stroke volume (SV) was measured using aortic diameter and pulsed Doppler velocity profile. SV was indexed for body surface area (SVI). Effective arterial elastance (Ea) was estimated by end-systolic pressure/SVI and total arterial compliance (Ca) by the ratio of pulse pressure/SVI. Quantitative B-mode ultrasound scans were used to measure intima-media thickness and diameters of the common carotid artery, and carotid stiffness (ß) was calculated. Using transcranial color Doppler, peak systolic, end-diastolic, and average peak flow velocities of middle cerebral artery were measured and pulsatile index (PI) as a parameter of vascular resistance was calculated. High sensitive C-reactive protein (hs-CRP), fasting glucose, insulin, and homeostasis model assessment for insulin resistance (HOMA-IR) were also assessed.
Results: Ea, Ca, IMT, ß index, and cerebral PI all increased significantly with BMI (r = 0.28, 0.35, 0.34, 0.27, and 0.41, p ≤ 0.01, respectively). There were significant relationships between BMI and fasting glucose (r = 0.18, p ≤ 0.05), insulin (r = 0.56, p ≤ 0.01), HOMA-IR (r = 0.55, p ≤ 0.01), and hs-CRP (r = 0.28, p ≤ 0.01). Ea, Ca, ß index, and cerebral PI correlated significantly with insulin (r = 0.28, 0.17, 0.24, and 0.36, p ≤ 0.05, respectively) and HOMA-IR (r = 0.25, 0.19, 0.27, and 0.51, p ≤ 0.05, respectively). In multivariate analysis, insulin and HOMA-IR were independent determinants of Ea, ß index, and cerebral PI. No significant relationships were observed between hs-CRP and Ea, Ca, IMT, ß index, and cerebral PI.
Conclusions: Obesity-related Insulin resistance associated with vascular functional changes may contribute to the increased prevalence of later cardiovascular diseases.
- © 2013 by American Heart Association, Inc.