Impact of Lifestyle-Related Diseases on Carotid Arterial Wall Elasticity as Evaluated by an Ultrasonic Phased-Tracking Method in Japanese Subjects

Abstract

We investigated the relationship between coronary risk factors and the intima-media thickness (IMT) and wall elasticity of carotid arteries. A new real-time ultrasonic measurement system that allows measurement of the elasticity of the carotid arterial intima-media complex was applied to 350 subjects, who were also checked for the presence/absence of hypertension, dyslipidemia, diabetes mellitus and regular smoking. Simultaneous measurement of the elastic modulus and IMT was conducted at four sites in the bilateral carotid arteries. In the group with maximum IMT (max IMT) <1.1 mm, the IMT, as well as the mean elastic modulus in the circumferential direction (Etheta), showed positive correlations with age and coronary risk factors. Multiple regression analysis showed that age, systolic blood pressure and pulse rate remained independent determinants of Etheta. The number of criteria fulfilling the diagnosis of metabolic syndrome showed a good positive correlation with the value of Etheta in the group with max IMT values <1.1 mm. Measurement of carotid arterial wall elasticity together with IMT is useful to detect dis-tortions in intramural elasticity distribution occurring in the early stages of atherosclerosis.