Protocol for Evaluating the Cardio-Ankle Vascular Index to Predict Cardiovascular Events in Japan: A Prospective Multicenter Cohort Study

INTRODUCTION: The cardio-ankle vascular index (CAVI) was developed in Japan and is a blood pressure-independent index of arterial stiffness from the origin of the aorta to the ankle. In recent years, it has been studied by many researchers worldwide, and it is strongly anticipated that it will play a role as a predictive factor for arteriosclerotic diseases. The objective of this study was to examine the benefits of using CAVI as a predictor of cardiovascular events in high-risk patients. METHODS AND DESIGN: This prospective multicenter study to evaluate the usefulness of the CAVI to predict cardiovascular events in Japan (CAVI-J) is a cohort study with central registration. Participants (n = 3,000) will be scheduled to enroll and data will be collected for up to 5 years from entry of participants into the study. To be eligible to participate in the CAVI-J study, individuals have to be aged between 40 and 74 years and have at least one of the following risk factors for arteriosclerosis: (1) type 2 diabetes mellitus; (2) high-risk hypertension; (3) metabolic syndrome; (4) chronic kidney disease (stage 3), or (5) history of coronary artery disease or noncardiogenic cerebral infarction. The primary endpoints of this study are cardiovascular death, nonfatal myocardial infarction, and stroke. The secondary endpoints are composite cardiovascular events including all cause death, angina pectoris with revascularization, new incidence of peripheral artery disease, abdominal aortic aneurysm, aortic dissection, heart failure requiring hospitalization, and deterioration in renal function. The cutoff for CAVI against the incidence of cardiovascular events will be determined.