P154 VASCULAR STRUCTURE AND FUNCTION IN RELATION TO WEIGHT EXCESS AND BLOOD PRESSURE IN A SAMPLE OF OBESE CHILDREN

Objective: To investigate the influence of weight excess and blood pressure (BP) on vascular structure and function in a sample of obese children. Methods: We measured office and ambulatory BP (ABPM), carotid intima-media thickness (cIMT), endothelial function by the Flow Mediated Dilation (FMD) technique, carotid distensibility (cDC) (ultrasonograph: LogiQ P5 Pro; software: Multimedia Video Engine II, DSP Lab, Pisa CNR, Italy) (1) and stiffness index (SI) by photopletismography (Pulce Trace PT1000, MicroMedical Ltd, UK) (2) in overweight and obese children (BMI > 90th percentile for sex and age). Results: Seventy children with weight excess were enrolled (age 11.5±2.4 years; female n: 30). cDC showed inverse correlation with BMI and waist circumference (rSpearman = −0.403 and rs = −0.346, respectively), 24h-SBP (rs = −0.449) and nighttime-SBP (rs = −0.490). SI inversely correlated with BMI (rs = −0.359) and waist/height ratio (rs = −0.303). When comparing normotensive and hypertensive children, as defined on the basis of the ABPM, no significant differences in vascular tests were found, although cDC tended to be lower in hypertensive. In normotensive subjects (n: 53) cIMT directly correlated with nighttime-SBP and DBP. Most of the correlations remained significant after adjustment for age, sex, BMI and BP. Conclusions: These data suggest that arterial elasticity is negatively affected by weight excess and 24h-BP levels even in childhood. In the normotensive subgroup it is detectable an effect of BP also on arterial structure.