Introduction: Our previous cross-sectional studies demonstrated a relationship between elevated cardiovascular risk factors and arterial stiffness in adolescents. Other investigators showed longitudinal associations between cardiovascular risk factors at age 9 and adult arterial stiffness. Therefore we sought to determine if risk factor-related increase in arterial stiffness could be demonstrated even earlier in childhood.
Hypothesis: In 10-year-old children, elevated blood pressure and BMI will be associated with less brachial distensibility (greater arterial stiffness).
Methods: A community sample of 232 children (age 9.6 ± 0.5 years, 52% male, 83% white) in follow up from a longitudinal study were enrolled and had the following measures collected: height, weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), brachial distensibility (BrachD, PulseMetric, San Diego, CA). Pearson correlation coefficients were calculated and general linear modeling was performed to evaluate the relationships between cardiovascular risk factors and arterial stiffness.
Results: Participants had a mean BMI of 18.6 ± 3.4 kg/m^2, waist-to-hip ratio (WHR) of 0.9 ± 0.05, BMI z-score of 0.5 ± 1.1, SBP of 96 ± 9 mm Hg, DBP of 53 ± 11 mm Hg, SBP z-score of -0.5 ± 0.8, DBP z-score of -0.7 ± 1, and BrachD of 7.4 ± 2.2 percent change per mm Hg. The following cardiovascular risk factors were significantly associated with BrachD: WHR (r = -0.19, p = 0.005), BMI z-score (r = -0.16, p = 0.01), and SBP z-score (r = -0.14, p = 0.04). Modeling revealed both WHR and BMI z-score but not SBP z-score were associated with BrachD independent of age, sex, and race. After reducing a model simultaneously adjusting for all multiple risk factors and demographic variables, WHR, race, and age remained independently associated with BrachD.
Conclusions: Associations between multiple cardiovascular risk factors (WHR, BMI, SBP) and arterial stiffness (brachial distensibility) are present in children as young as 10 years old, with WHR maintaining an independent association in a model adjusted for multiple covariates. These findings build on previous evidence that early exposure to cardiovascular risk factors can affect vascular health and support the contention that threats to cardiovascular health should be met aggressively in childhood.