Abstract 10852: Temporal Trends in Pulse Pressure for U.S. Children During the Rise of Obesity
Background: Excess weight increases cardiovascular disease (CVD) risk in part by impairing aortic function. Pulse pressure (PP), a measure of aortic function, predicts hypertension and CVD events. Temporal trends in PP during the pediatric obesity epidemic are unknown.
Methods: We retrieved demographics, anthropometrics, and at least 2 blood pressure (BP) measurements in 1638 to 3663 children 8-17 years old from the cross-sectional National Health and Nutrition Examination Surveys (NHANES) 1976-2008. Survey-weighted linear regression was used to examine secular trends in PP across NHANES periods and assess the effects of obesity (body mass index >95%), while adjusting for age, sex, height, heart rate, mean arterial pressure (MAP), and race/ethnicity.
Results: Comparing NHANES II (1976-80) vs NHANES 2007-8, unadjusted PP was higher (40±0.4 vs 48±0.6 mm Hg, p<0.0001 for trend) while systolic BP (109±0.6 vs 106±0.6 mm Hg, p=0.03) and MAP (82±0.5 vs 74±0.5 mm Hg, p<0.0001) were lower. After multivariable adjustment, PP widened over time in boys and girls (Table 1). Adjusting for obesity attenuated this secular trend. Significant interactions were noted for height-obesity and age-obesity (p≤0.0002). PP increased with height (per cm) in boys (0.23 [0.19-0.28] mm Hg, p<0.0001) and girls (0.10 [95%CI 0.06-0.15] mm Hg, p<0.0001). Obesity amplified PP relations with height 35 to 90% (obese boys: 0.31 [0.25-0.37] mm Hg, p<0.0001; obese girls: 0.19 [0.13-0.25] mm Hg, p<0.0001). In boys, PP was higher with greater age and the relation was amplified by obesity (non-obese: 0.64 [0.42-0.85] mm Hg, p<0.0001; obese: 1.03 [0.72-1.35] mm Hg, p<0.0001).
Conclusions: PP has increased substantially in children over the past 30 years, in part due to increasing prevalence of obesity. Obesity amplifies sex-specific relations between PP and height, possibly by impairing aortic remodeling and proper matching between aortic diameter and flow during rapid growth.
- © 2011 by American Heart Association, Inc.