Objective: To investigate the distribution of peripheral arterial stiffness, endothelial function and their correlations with cardiovascular risk factors in the 7-17 year-olds.
Methods: Normal weight and obese subjects aged 7-17 years with completed data on questionnaires, anthropometric and blood biochemical tests, were recruited from a cross-sectional population-based study on childhood hypertension in Minhang district of Shanghai. Automatic waveform analyzer (BP-203RPE-I) and Endopat 2000 were used to measure the arterial stiffness. Endothelial function with brachial-ankle pulse wave velocity (baPWV) and reactive hyperemia index (RHI) were recorded. BaPWV and RHI were standardized by age. Skewed biochemical variables were log transformed. Linear correlation analysis was performed to observe association between baPWV, RHI and other measured variables.
Results: A total of 452 normal-weight and 94 obese subjects were recruited, including 299 males. Data showed that baPWV and RHI increased with age in normal weight subjects(r=0.33, P<0.01; r=0.36, P<0.01). RESULTS from Linear correlation analysis revealed that baPWV was positively correlated with BMI (r=0.13, P=0.002), systolic blood pressure (SBP) (r=0.20, P<0.01), diastolic blood pressure (DBP) (r=0.27, P<0.01), triglycerides (TG) (r=0.11, P=0.010), insulin (r=0.21, P=0.004) and the HOMA insulin resistance index (r=0.21, P=0.005), but negatively correlated with high-density lipoprotein cholesterol (r=-0.09, P=0.039). RHI was positively correlated with BMI (r=0.10, P=0.018) but negatively correlated with DBP (r=-0.10, P=0.016). Males had higher baPWVs than females (P=0.04). However, RHI did not differ between genders.
Conclusions: The fact that baPWV and RHI increased along with age, indicated that the arterial stiffness and endothelial function continued to develop in normal weight childhood and adolescence. Arterial stiffness was correlated with cardiovascular risk-related parameters whereas endothelial function was not. BaPWV might be more sensitive in evaluating the cardiovascular risk in children and adolescents than RHI did.