Are you as old as your arteries? Comparing arterial aging in Japanese and European patient groups using cardio-ankle vascular index

Background: Most comparisons of arterial stiffness between ethnic groups focus on pulse wave velocity. This study used the cardio-ankle vascular index (CAVI) in European compared to Japanese individuals to investigate how cardiovascular risk factors affect arterial aging across geographic regions. Methods: Four hundred and ninety-four European and 1044 Japanese individuals underwent measurements of CAVI, blood pressure and information on cardiovascular risk factors. Both datasets included individuals with 0-5 cardiovascular risk factors. Results: Average CAVI was higher in the Japanese than the European group in every age category, with significant differences up to 75 years for males and 85 for females. The correlation of CAVI with age, controlled for cardiovascular risk factors, was slightly higher in Japanese females (r = 0.594 vs. Europeans r = 0.542) but much higher in European males (r = 0.710 vs. Japanese r = 0.511). There was a significant correlation between CAVI and total cardiovascular risk factors in the Japanese (r = 0.141, P < 0.001) but not the European group. On linear regression, average CAVI was significantly dependent on age, sex, diabetes, BMI, SBP and geographic region. When divided into 'healthy' vs. 'high risk', the healthy group had a steeper correlation with age for Europeans (r = 0.644 vs. Japanese r = 0.472, Fisher's Z P < 0.001), whereas in the high-risk group, both geographic regions had similar correlations. Conclusion: Japanese patient groups had higher arterial stiffness than Europeans, as measured by CAVI, controlling for cardiovascular risk factors. Europeans had greater increases in arterial stiffness with age in healthy individuals, particularly for males. However, cardiovascular risk factors had a greater impact on the Japanese group.