Carotid artery stiffness and risk of vascular events and mortality: the REGICOR study

Abstract

Introduction and objectives: The aims of this study were to determine the dose-response association of carotid arterial stiffness with vascular outcomes and overall mortality, and to assess their added predictive capacity. Methods: Population-based cohort study including 6468 individuals, with a median follow-up of 6.5 years. Six carotid artery stiffness indices were assessed: strain, stiffness, Peterson elasticity coefficient, compliance coefficient, distensibility coefficient, and pulse wave velocity (PWV). Incident coronary, cerebrovascular, global vascular, and total fatal events were identified. Results: Carotid compliance and distensibility coefficients were not associated with any of the outcomes. Carotid stiffness, Peterson elasticity coefficient, and PWV showed a direct linear relationship to cerebrovascular disease: the risk increased by 8% (95%CI, 1-16) per stiffness unit increase, by 7% (95%CI, 2-13) per 10-unit Peterson elasticity coefficient increase, and by 26% (95%CI, 8-48) per PWV unit increase. Carotid strain showed a nonlinear association with ischemic heart disease. When strain was ≤ 0.09 units, each 0.01-unit increase was associated with a 15% lower risk of coronary events (95%CI,-33 to 6); above 0.09 units, each 0.01 increase in strain was associated with a 16% higher risk of coronary events (95%CI, 6-27). The addition of the stiffness indices did not improve the predictive capacity of validated risk functions. Conclusions: Carotid stiffness, Peterson elasticity coefficient, and PWV have a direct linear association with cerebrovascular disease risk. Carotid strain is not linearly related to U-shaped ischemic heart disease risk. The inclusion of these indexes does not improve the predictive capacity of risk functions.