Arterial stiffness and pulse-pressure amplification in overweight/obese African-American adolescents: relation with higher systolic and pulse pressure.

BACKGROUND: Obesity is associated with a higher systolic blood pressure (BP) and pulse pressure (PP) in African-American youths, increasing their risk for developing hypertension. However, it is unknown whether arterial stiffness and wave reflection are associated with a higher systolic BP and PP or with smaller PP amplification in overweight/obese (OW/OB) African-American adolescents.
METHODS: We measured carotid-femoral pulse wave velocity (CF-PWV), carotid-radial PWV (CR-PWV), the augmentation index (AIx) adjusted to a heart rate of 75 bpm (AI75), the augmentation pressure (AugP), PP amplification, and body composition in 227 healthy African-American adolescents (age, 16.9 ± 0.2 years; 54% male).
RESULTS: Adolescents who were OW/OB (n = 86, body mass index (BMI) ≥ 85th percentile) demonstrated 5%-6%, 13%-16%, and 2.5% higher aortic and brachial systolic BP, brachial and aortic PP, and mean arterial pressure (MAP), respectively (all P < 0.05), than adolescents of normal-weight (NW, n = 141, BMI < 85th percentile). The OW/OB adolescents had a 7% higher CF-PWV, 5% lower CR-PWV, and 3.5% lower PP amplification than the NW group (all P < 0.05), but no differences in AI75 or AugP. In the entire cohort after adjustment for age, sex, heart rate, height, and MAP, CF-PWV was positively correlated, and CR-PWV and PP amplification were negatively correlated, with total and abdominal/hip adiposity. Additionally, CF-PWV, AI75, and AugP were positively correlated with MAP and negatively correlated with PP amplification. CR-PWV, AI75, and AugP were negatively correlated with brachial and aortic PP.
CONCLUSIONS: Higher aortic stiffness is associated with smaller PP amplification with increasing adiposity in African-American adolescents. Whether a reduction in PP amplification predicts increased CVD risk in obese African-American adolescents requires further study.