ABSTRACT: Ultrasound measurements of arterial stiffness are associated with atherosclerosis risk factors, but limited data exist on their association with incident cardiovascular events. We evaluated the association of carotid ultrasound-derived arterial stiffness measures with incident coronary heart disease (CHD) and ischemic stroke in the Atherosclerosis Risk in Communities (ARIC) study.Carotid arterial strain and compliance, distensibility and stiffness indices, pressure-strain, and Young elastic moduli were measured in 10 407 individuals using ultrasound. Hazard ratios for incident CHD (myocardial infarction, fatal CHD, coronary revascularization) and stroke in minimally adjusted (age, sex, center, race) and fully adjusted models (minimally adjusted model+diabetes, height, weight, total cholesterol, high-density lipoprotein cholesterol, tobacco use, systolic blood pressure, antihypertensive medication use, and carotid intima-media thickness) were calculated.The mean age was 55.3 years. Over a mean follow-up of 13.8 years, 1267 incident CHD and 383 ischemic stroke events occurred. After full adjustment for risk factors and carotid intima-media thickness, all arterial stiffness parameters (carotid arterial strain hazard ratio [HR], 1.14 [95% CI, 1.02-1.28]; arterial distensibility HR, 1.19 [1.02-1.39]; stiffness indices HR, 1.14 [1.04-1.25]; pressure-strain HR, 1.17 [1.06-1.28]; Young elastic moduli HR, 1.13 [1.03-1.24]), except arterial compliance (HR, 1.02 [0.90-1.16], were significantly associated with incident stroke but not with CHD.After adjusting for cardiovascular risk factors, ultrasound measures of carotid arterial stiffness are associated with incident ischemic stroke but not incident CHD events despite that the 2 outcomes sharing similar risk factors.URL: www.clinicaltrials.gov. Unique identifier: NCT00005131.