Various Indices of Arterial Stiffness: Are They Closely Related or Distinctly Different?

Arterial stiffness is an independent risk factor for cardiovascular disease. There are a number of techniques and devices that have been developed and utilized to capture the information pertaining to the elasticity of the blood vessel. Almost all the available indices of arterial stiffness are known to increase with advancing age and are elevated in the presence of hypertension and coronary heart disease. It is not known how closely these different measures of arterial stiffness are related to each other. Available evidence indicates that arterial stiffness indices that share a homogeneous methodology appear to demonstrate good correlations. However, there are no significant associations between some measures. These overall results may be surprising considering that all the indices are supposed to reflect the same property of the arterial wall (i.e., arterial elasticity). Interestingly, no or weak correlations between indices of vascular function are not confined only to arterial stiffness and can be extended to endothelial function and vascular reactivity measures.