Relation of Pulse Wave Velocity to Contemporaneous and Historical Blood Pressure in Female Twins

Background:An association between blood pressure and aortic stiffness is well known, but ambiguity remains as to whether one precedes the other. This study aimed to investigate the association of aortic stiffness with contemporaneous versus historic blood pressure and direction of causality between aortic stiffening and hypertension in female twins. Methods:Aortic stiffness, measured by carotid-femoral pulse wave velocity (PWV), and mean arterial pressure (MAP) was recorded in 2037 female TwinsUK participants (mean age: 62.4 +/- 9.7 years) at a single time point. A subset of 947 participants had repeat PWV and MAP measures (mean interval 5.5 +/- 1.7 years) with additional historic MAP (mean interval 6.6 +/- 3.3 years before baseline). Results:Cross-sectional multivariable linear regression analysis confirmed PWV significantly associated with age and MAP. In longitudinal analysis, annual progression of PWV was not associated with historic MAP (standardized beta coefficient [beta]=-0.02, P=0.698), weakly associated with baseline MAP (beta=0.09, P=0.049) but strongly associated with progression (from baseline to most recent measurement) of MAP (beta= 0.26, P<0.001). Progression of MAP associated with both baseline and progression of PWV (beta=0.13, P=0.003 and beta=0.24, P<0.001, respectively). Conclusions:Progression of aortic stiffness associates more strongly with contemporaneous MAP compared with historic MAP. In contrast, progression of MAP is associated with prior arterial stiffness. These findings suggest a bidirectional relationship between arterial stiffness and blood pressure, and that lowering blood pressure may prevent a cycle of arterial stiffening and hypertension.