Sexual differences in central arterial wave reflection are evident in prepubescent children

Objective: The objective of this study was to examine the influence of sex on central arterial wave reflection in healthy prepubescent children matched for body size and cardiorespiratory fitness. Methods: Fifty-five healthy children (9.8 +/- 1.0 years, 44% girls) were recruited. Cardiorespiratory fitness was assessed using a treadmill-based graded exercise test to volitional exhaustion. Pulse wave analysis was used to measure augmentation index (AIx) and central blood pressures. Results: The girls and boys were matched for age, body size and cardiorespiratory fitness. There were no significant differences between sexes for heart rate or central blood pressure parameters. Girls demonstrated a significantly greater AIx than the boys (8.9 +/- 9.3 vs. 1.9 +/- 10.8%, P = 0.015, d = 0.69). Conclusion: Sexual differences in central arterial wave reflection exist prepubescence, independent of stature or cardiorespiratory fitness. Further study is required to elucidate the mechanism(s) explaining this phenomenon and to determine the influence of wave reflections on left ventricular mass during childhood.