Associations of noninvasive measures of arterial compliance and ankle-brachial index: The multi-ethnic study of atherosclerosis (MESA)

Background The association between measures of arterial compliance and peripheral arterial disease (PAD) is unclear. Early changes in arterial wall compliance could be a useful marker of patients at high risk for developing lower extremity atherosclerosis. Methods We used linear and logistic regression models on baseline data from 2,803 female and 2,558 male participants in the Multi-Ethnic Study of Atherosclerosis (MESA) to study associations between tonometry-derived baseline measures of arterial compliance (large artery compliance (C1) and small artery compliance (C2)) and the baseline ankle-brachial index (ABI), as well as change in the ABI over ∼3 years of follow-up. Results In cross-sectional analyses, lower C1 and C2 values, indicating poorer arterial compliance, were associated with lower ABI. There were significant linear trends across strata of ABI, especially in C2 which ranged from 3.7 ml/mm Hg × 100 (95% confidence interval (CI) 3.3-4.2) in women with an ABI 0.90 to 4.2 ml/mm Hg × 100 (95% CI 4.1-4.3 P < 0.001) in women with ABI 1.10-<1.40. Similar significant trends (P < 0.001) were seen in men. In prospective analyses, those with the lowest tertile of C2 values at baseline had a greater multivariable-adjusted odds for decline in ABI of ≤0.15 over 3 years compared to those with the highest C2 values at baseline (odds ratio (OR) 1.80, 95% CI 1.23-2.64). Conclusions We observed that less compliant arteries were significantly associated with low ABI in cross-sectional analysis and with greater decline in odds of ABI over time.