The Aging of Elastic and Muscular Arteries

Abstract

OBJECTIVE -To compare age-related changes in the mechanical properties of different arterial segments in normal volunteers and subjects with type 2 diabetes.RESEARCH DESIGN AND METHODS -In 169 subjects (diabetic n ϭ 57 and nondiabetic n ϭ 112), we assessed the mechanical properties of three arterial segments of differing wall composition. Pulse wave velocity (PWV) was measured noninvasively in a thoracoabdominal segment (carotid femoral PWV [PWV cf ]), in an upper limb muscular artery (carotid radial PWV [PWV cr ]), and from the aorta to the finger (PWV from the aorta to the finger [PWV fin ]). Central aortic compliance (CAC) was also measured.RESULTS -Average CAC was lower (0.662 vs. 0.850, P Ͻ 0.05) and all measures of PWV tended to be faster in diabetic subjects despite the fact that they were, on average, 10 years younger. However, these measures were not related to age in diabetic subjects. After correcting for blood pressure, only PWV cf was associated with age in nondiabetic subjects (P Ͻ 0.001). Expressing results as ratios of nonelastic to elastic arterial segments (i.e., PWV cr -to-PWV cf and PWV fin -to-PWV cf ) improved the relationship with age. Both PWV cr -to-PWV cf and PWV fin -to-PWV cf were significantly associated with age in nondiabetic subjects (r ϭ Ϫ0.59, P Ͻ 0.001; r ϭ Ϫ0.57, P Ͻ 0.001) but not in diabetic subjects (r ϭ Ϫ0.15, P ϭ 0.302; r ϭ Ϫ0.24, P ϭ 0.129). Multivariate analysis showed that the ratios were not associated with systolic blood pressure.CONCLUSIONS -There are significant differences in the rate of age-related decline in vascular stiffness in elastic arteries of nondiabetic compared with diabetic arteries. Diabetic arteries appear to age at an accelerated rate at an earlier age and then reach a functional plateau. Diabetes Care 26:2133-2138, 2003T he mechanical properties of the large conduit arteries are now recognized as an important component of cardiovascular pathophysiology. Less compliant arteries are associated with suboptimal cardiac energy supplydemand balance with reduced subendocardial blood flow and increased left ventricular afterload (1). There are also adverse effects of poor compliance on wave reflection and systolic blood pressure (SBP) (2). It is usually accepted that the age-related increase in SBP and decrease in diastolic blood pressure (DBP) are largely due to decreased proximal aortic compliance, causing more rapid diastolic run-off of a lower-contained volume (hence decreasing DBP) along with an early return of the reflected pressure wave in systole, causing increased pressure augmentation (increased SBP). Thus, increased aortic stiffness is the predominant cause of increased pulse pressure (3).Pulse pressure is a marker of cardiovascular risk in a general population (4) and, independent of SBP and DBP, has been shown to be a predictor of cardiovascular events (5), particularly in older individuals (6). It has also been shown that aortic stiffness (measured as pulse wave velocity [PWV]) is an independent predictor of cardiovascular risk (7) and all-ca...

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Arterial stiffness, ambulatory blood pressure and low-grade albuminuria in non-diabetic African and Caucasian men: the SABPA study

“…Like the more commonly used brachial-ankle pulse wave velocity, results obtained are from a combination of both elastic and muscular arteries. 49 However, the pulse wave velocity in this study correlated well with 24 h systolic (r¼0.32, Po0.01) and diastolic blood pressure (r¼0.32, Po0.01) and showed a tendency with 24 h pulse pressure (r¼0.20, P¼0.10). We used daytime and night time pulse pressure as an indirect measure of aortic stiffness.…”

Arterial stiffness in a muscular artery in women with longstanding rheumatoid arthritis compared with healthy controls and patients with traditional cardiovascular risk factors

“…One of the main diVerences is that the stiVness of elastic arteries is strongly linked to age when the elastic Wbers break down. In contrast to that, age has only minimal inXuence on muscular arteries [17][18][19].…”

“…According to the Windkessel theory, large, elastic arteries act as a reservoir, from which the blood Xows further to the peripheral arteries, which work as non-elastic conduits [16]. While the aorta consists of more elastic elements [17], the arteries of the upper limb for instance are of a muscular type [18]. One of the main diVerences is that the stiVness of elastic arteries is strongly linked to age when the elastic Wbers break down.…”