Association between arterial stiffness and peripheral artery disease as measured by radial artery tonometry.

OBJECTIVE: Arterial stiffness and peripheral artery disease (PAD) are both associated with an elevated risk of major adverse cardiac events; however, the association between arterial stiffness and PAD is less well characterized. The goal of this study was to examine the association between parameters of radial artery tonometry, a noninvasive measure of arterial stiffness, and PAD.

METHODS: We conducted a cross-sectional study of 134 vascular surgery outpatients (controls, 33; PAD, 101) using arterial applanation tonometry. Central augmentation index (AIX) normalized to 75 beats/min and peripheral AIX were measured using radial artery pulse wave analysis. Pulse wave velocity was recorded at the carotid and femoral arteries. PAD was defined as symptomatic claudication with an ankle-brachial index of <0.9 or a history of peripheral revascularization. Controls had no history of atherosclerotic vascular disease and an ankle-brachial index ≥0.9.

RESULTS: Among the 126 participants with high-quality tonometry data, compared with controls (n = 33), patients with PAD (n = 93) were older, with higher rates of hypertension, hyperlipidemia, diabetes, and smoking (P < .05). Patients with PAD also had greater arterial stiffness as measured by central AIX, peripheral AIX, and pulse wave velocity (P < .05). In a multivariable model, a significantly increased odds of PAD was associated with each 10-unit increase in central AIX (odds ratio, 2.1; 95% confidence interval, 1.1-3.9; P = .03) and peripheral AIX (odds ratio, 1.9; 95% confidence interval, 1.2-3.2; P = .01). In addition, central and peripheral AIX were highly correlated (r120  = 0.76; P < .001).

CONCLUSIONS: In a cross-sectional analysis, arterial stiffness as measured by the AIX is independently associated with PAD, even when adjusting for several atherosclerotic risk factors. Further prospective data are needed to establish whether radial artery tonometry could be a tool for risk stratification in the PAD population.