Relationship between arterial elasticity indices and carotid artery intima-media thickness

Functional and structural changes of the arterial wall appear to serve as e arly hallmarks of the hypertensive disease process. Structural vascular cha nges can be studied by the determination of the intima-media wall thickness (IMT) at the carotid artery. The elastic behavior of the proximal and dist al parts of the arterial tree can be assessed from noninvasively recorded r adial artery waveforms. The aim of the study was to compare large (proximal , C1) and small (distal, C2) artery elasticity indices in two age-matched s tudy groups with high- and low-normal blood pressure (BP) and to assess the relation between elasticity indices and IMT. A total number of 22 subjects with high-normal BP (40 +/- 2 years; BP, 147 +/- 2.5/84 +/- 1.5 mm Hg) and 22 matched controls with low-normal BP (40 +/- 2 years; BP, 123 +/- 1.9/69 +/- 1.5 mm Hg) were enrolled. The IMT was echographically determined at the common carotid artery by the leading-edge technique. Large artery (C1) and small artery (C2) elasticity indices were calculated from a third- order, four-element model of the arte rial circulation. In the group with high-normal BP large and small artery e lasticity indices were significantly decreased ver sus controls with low-no rmal BP (C1: 1.63 +/- 0.08 nu 1.99 +/- 0.09 mL/mm Hg, P < .01; C2: 0.059 +/ - 0.005 <nu> 0.076 +/- 0.007 mL/mm Hg, P < .05) and IMT increased significa ntly (0.607 +/- 0.039 <nu> 0.516 +/- 0.027 mm, P < .05). Moreover, there wa s an inverse relationship between IMT and small artery elasticity index (r = -0.60, P = .004). In subjects with a high-normal BP there is already a change in the IMT of t he carotid artery versus normotension. The IMT is related to the small arte ry elasticity index (C2). Am J Hypertens 2000;13:1226-1232 (C) 2000 America n Journal of Hypertension, Ltd.