Blood pressure independence of the aortic-femoral arterial stiffness gradient in healthy young adults

Purpose Pulse wave velocity (PWV) is a widely used marker of arterial stiffness but is inherently blood pressure (BP)-dependent. The aortic-femoral stiffness gradient (af-SG) has been proposed as a potentially BP-independent index of vascular stiffness in older adults; however, whether this BP independence is preserved in young adults remains unclear. Methods This study examined the association of carotid-femoral PWV (cfPWV) and femoral-ankle PWV (faPWV) and af-SG (faPWV/cfPWV) with BP components in 20 healthy young adults (10 men, 10 women; age 21 ± 2 years). Pearson correlation analyses were performed to assess associations with systolic BP, diastolic BP, mean arterial pressure, and pulse pressure. Results cfPWV was significantly correlated with systolic BP (r = 0.754), diastolic BP (r = 0.503), and mean arterial pressure (r = 0.654) (all P < 0.05), but not with pulse pressure (r = 0.366, P = 0.112). faPWV was also significantly correlated with systolic BP (r = 0.609) and mean arterial pressure (r = 0.509). In contrast, af-SG was not significantly correlated with any BP component (all P > 0.05). Conclusion These findings suggest that the BP independence of af-SG is already evident in healthy young individuals and is not solely attributable to age-related vascular remodeling. Thus, af-SG may provide a BP-independent index of vascular stiffness from early adulthood.