Arterial stiffness, but not endothelium-dependent vasodilation, is related to a low Ankle-Brachial index. The Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS).

BACKGROUND

Arterial compliance and endothelium-dependent vasodilation are two characteristics of the vessel wall. In the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study we studied the relationships between arterial compliance and endothelium-dependent vasodilation versus the Ankle-Brachial index (ABI), a clinically used index of peripheral artery disease.

METHODS

In the population-based PIVUS study (all aged 70), arterial compliance was determined by ultrasound as the distensibility of the carotid artery and the stroke volume to pulse pressure (SV/PP) ratio by echocardiography, while endothelium-dependent vasodilation was assessed by the invasive forearm technique with acetylcholine (EDV) and brachial artery ultrasound (FMD) in 519 subjects in whom the Ankle-Brachial index was investigated.

RESULTS

After adjustments for gender and Framingham risk score, distensibility in the carotid artery and the SV/PP ratio were significantly reduced in subjects with a reduced ABI (< 0.9) in both legs (n=15, P = 0.0006 and P = 0.0003, respectively). Endothelium-dependent vasodilation was not significantly related to a reduced ABI.

CONCLUSION

A reduced arterial compliance, but not endothelium-dependent vasodilation, was related to a low ABI in both legs after adjustment for major risk factors, suggesting that atherosclerosis in the leg arteries is associated with arterial compliance also in other parts of the vasculature.