Cardiorespiratory fitness is a strong predictor of the cardio-ankle vascular index in hypertensive middle-aged and elderly Japanese men

Aim: This study aimed to examine whether cardiorespiratory fitness (CRF) is associated with arterial stiffening, evaluated using the cardio-ankle vascular index (CAVI), independent of visceral fat (VF) in middle-aged and elderly Japanese men. We also examined whether the relationship between CRF and the CAVI is modified by age and/or hypertension. Methods: The CAVI was determined in 157 Japanese men (age range, 30-79 years), including 96 hypertensive subjects (61.1%). CRF was assessed by measuring the peak oxygen uptake (V4O2peak). The subjects were divided into low- and high-CRF groups, and the VF area was assessed using magnetic resonance imaging. Results: The V4O2peak correlated with the CAVI following adjustment for age and body mass index in the middle-aged and elderly groups (all the subjects: r =－0.285, p＜0.001; middle-aged: r =－0.240, p= 0.040; elderly: r =－0.225, p=0.049). VF also correlated with the CAVI (r =0.230, p=0.004). A multiple linear regression analysis revealed that age (β=0.406, p＜0.001) and the V4O2peak (β=－0.186, p=0.015) were associated with the CAVI independently of VF and the mean blood pressure. Twoway ANCOVA adjusted for age demonstrated that the hypertensive individuals had higher CAVI values than the normotensive individuals in the low-CRF group, whereas no significant differences in the CAVI were observed in the high-CRF group (p for interaction ＜0.05). Conclusions: In the present study, CRF was found to be associated with the CAVI, independent of age and VF, in hypertensive middle-aged and elderly Japanese men.