Arterial Wall Structure and Dynamics in Type 2 Diabetes Mellitus Methodological Aspects and Pathophysiological Findings

Type 2 Diabetes Mellitus (DM), or adult-onset diabetes, is being considered as a new pandemic. Cardiovascular disease is the major cause of morbidity and mortality in type 2 DM, due to arterial structure and functional changes. Assessment of arterial structure and biomechanics, by non-invasive methods and parameters, can be used to detect early alterations related to DM. Three markers of vascular disease may help to a better evaluation of vascular dysfunction in type 2 DM patients: carotid intima-media thickness (IMTc), arterial stiffness, assessed by pulse wave velocity (PWV), and endothelial function, evaluated through the brachial artery flow-mediated dilation (FMD). Among these parameters, IMTc is considered a marker of structural vessel wall properties, and arterial stiffness reflects functional wall properties. Endothelial function represents the arterial way to actively regulate its diameter (smooth muscle-dependent actions) and its visco-elastic properties (wall elasticity and viscosity). IMTc is increased in patients with type 2 DM and other independent risk factors, such as: age, hyperlipidemia and duration of DM. Subjects with DM have shown increased arterial stiffness. Type 2 DM is associated with reductions in FMD (endothelial dysfunction), which has already been reported to be inversely and strongly related to the extent of hyperglycemia. The underlying patho-physiological mechanisms are complex and remain to be fully elucidated. A complete understanding of the association between arterial alterations and early detection, and type 2 DM, may be critical for the primary prevention of DM-related macro-vascular disease.