Abstract
Heart-brachium pulse wave velocity (hbPWV) is a promising measure of arterial stiffness including the proximal aorta. To characterize age-associated changes and the clinical utilities of hbPWV, we evaluated the impacts of age and cardiovascular disease (CVD) risks on hbPWV cross-sectionally (N = 7868) and longitudinally (N = 3710, followed by 9.1 ± 2.0 years). hbPWV were obtained using two validated equations for arterial path length (with and without considering age-related aortic elongations). Brachial-ankle pulse wave velocity (baPWV) was used as a comparative measure. Repeated-measures correlation (rmcorr) and regression analyses were used to characterize associations of PWVs with age and Framingham's general CVD risk score (FRS). In the cross-sectional study, hbPWVs derived by both equations showed stronger correlation with age (r = 0.746 ~ 0.796) and FRS (r = 0.714-0.749) than baPWV (r = 0.554 and r = 0.643). Furthermore, hbPWVs correlated with FRS even after controlling for age (r = 0.260 ~ 0.269, P < 0.0001). In the longitudinal study, hbPWVs demonstrated significantly higher rmcorr coefficient with age than baPWV (r(rm)=0.439-0.511 vs. 0.307, P < 0.0001). Across the adult lifespan, age-related increases in hbPWVs were almost consistent, starting from young adults, while baPWV displayed accelerated increases with age. A receiver operating characteristic curve analysis indicated that hbPWVs depicted more robust ability to stratify general CVD risk compared with baPWV (AUC = 0.896-0.913 vs. 0.833, P < 0.0001). The results of the follow-up study were consistent with the findings of the cross-sectional investigation. Our findings suggest that hbPWV undergoes a linear augmentation with age, commencing from an early adult life stage onward, rendering it a potential marker for discerning CVD risk.