Abstract P299: BMI and BP Predict Brachial Distensibility in Healthy Adolescents and Young Adults
Introduction: CV risk-factor (CVRF) related increase in arterial stiffness is associated with adverse CV events in adults. Cross-sectional studies in youth show a relationship between CVRF and arterial stiffness. Longitudinal data are lacking. Hypothesis: CVRFs will predict decreased brachial artery distensibility (BrachD).
Methods: Demographics, anthropometrics, BP, fasting glucose, insulin, lipids and BrachD were measured in 425 healthy youth in a school-based longitudinal cohort (age 17.4 +2.1 yrs, 41% male, 61% Caucasian). Anthropometrics, BP and BrachD were repeated 2.1 + 0.3 years later. Mean values for baseline and follow-up variables were evaluated by paired t-test. Characteristics of subjects with decrease in BrachD (N=167) were compared by t-test with subjects without BrachD decrease. The multivariable model to determine predictors of follow-up BrachD contained baseline and change of age, sex, BMI, MAP, HR, baseline lipids, glucose and insulin.
Results: Over 2 years, the cohort increased in HT, WT, BMI, SBP and BrachD (all p<0.02). Predictors of decrease in BrachD were greater baseline and change in BMI, MAP and HR (R2 = 0.36, model p <0.0001, parameter p< 0.02, BrachD at follow-up = 2.7 + 0.04*Age at baseline + 0.4*Sex (male=1, female=2) − 0.02 Age at baseline*Sex − 0.33*BMI at baseline − 0.02*BMI change - 0.005*MAP at baseline - 0.004*MAP change - 0.002*HR at baseline - 0.003*HR change). BMI at baseline and change in BMI contributed the majority of the variance in BrachD at follow-up (16 and 4%). Subjects with decrease in BrachD were more likely to have gained more BMI (1.3 vs 0.6 kg/m2) or increased more in MAP (0.8 vs −1.3 mmHg) and HR (1.1 vs −2.0 beats/min, all p<0.002).
Conclusions: Development of obesity with subsequent changes in BP and HR may lead to development of arterial dysfunction. Prevention of obesity may be the most important approach to improve the CV health of adolescents and young adults.
- © 2012 by American Heart Association, Inc.