Author(s): LIU, J., KUNIMATSU, N., OGOH, S., Institution: TOYO UNIVERSITY, Country: JAPAN, Abstract-ID: 1352

INTRODUCTION:
Pulse wave velocity (PWV) is widely used as an index of arterial stiffness and vascular health; however, it is influenced by blood pressure (BP). The aortic-femoral arterial stiffness gradient (af-SG), defined as the ratio of femoral-ankle PWV (faPWV) to carotid-femoral PWV (cfPWV), has been proposed as a BP-independent index in older adults [1, 2]. However, evidence from the ratio of aortic-to-brachial artery stiffness (ab-ratio) suggests that this BP independence may not be preserved in young individuals [3]. Moreover, it remains unknown whether the pressure dependence of af-SG reflects intrinsic characteristics of lower-limb vascular anatomy or physiological changes associated with age-related arterial stiffening. Therefore, this study examined the association between BP indices and af-SG in healthy young adults.
METHODS:
Twenty-eight healthy young adults (12 men, 16 women; age 21 ± 2 years) participated in this study. Brachial BP was measured in the supine position after a 10-minute rest period. Central arterial stiffness was assessed using cfPWV (SphygmoCor XCEL), whereas peripheral arterial stiffness was evaluated using femoral-ankle PWV (faPWV, PCU-2000). The af-SG was calculated as the ratio of faPWV to cfPWV. Pearson correlation analyses were performed to examine the associations between PWV indices and systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP).
RESULTS:
The cfPWV was strongly and positively correlated with SBP (r = 0.788, P < 0.001), DBP (r = 0.582, P = 0.001), MAP (r = 0.730, P < 0.001), and PP (r = 0.389, P = 0.041). The faPWV was significantly associated with SBP (r = 0.467, P = 0.012) and PP (r = 0.389, P = 0.041), but showed no significant associations with DBP or MAP. In contrast, the af-SG was not significantly correlated with SBP, DBP, MAP, or PP (all P > 0.05).
CONCLUSION:
In healthy young adults, af-SG remained independent of SBP, DBP, MAP, and PP despite the significant pressure dependence of central and peripheral PWV. These findings suggest that the BP independence of af-SG is preserved in early adulthood and may reflect intrinsic vascular properties rather than secondary effects of age-related arterial stiffening.

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