Aortic Calcium: epidemiology and progression

描述（由申请人提供）：主动脉钙，通过计算机断层扫描测量，比其他亚临床（即无症状）心血管疾病（CVD）标志物发生得更早，范围更广，在女性中很常见。主动脉的大尺寸和相对较少的运动图像伪影使其成为放射定量成像的理想选择。该应用与多种族动脉粥样硬化研究（MESA）相协调，MESA是一项大型前瞻性流行病学研究，调查多种亚临床CVD措施和CVD危险因素。MESA的亚临床测量包括冠状动脉钙、颈动脉超声、心脏磁共振成像和踝/肱血压指数。广泛的心血管疾病危险因素测量包括传统的危险因素和较新的测量方法，如炎症和遗传标记。

DESCRIPTION (provided by applicant): Aortic calcium, measured by computed tomography, occurs earlier in life than other subclinical (that is, asymptomatic) markers of cardiovascular disease (CVD), shows a wide range, and is common in women. The large size of the aorta and relative lack of image artifact from motion make it ideal for radiographic quantitative imaging. This application is coordinated with the Multi-Ethnic Study of Atherosclerosis (MESA), a large prospective epidemiologic study investigating multiple subclinical CVD measures and CVD risk factors. Subclinical measures in MESA include coronary calcium, carotid ultrasound, cardiac magnetic resonance imaging, and the ankle/brachial blood pressure index. The extensive CVD risk factor measurements include both traditional risk factors and newer measures such as inflammatory and genetic markers. The primary long-term objective of this application is to determine the epidemiology of aortic calcium. 2000 randomly selected (from 6500 total) MESA participants will be studied. Questions to be addressed include predictors of aortic calcium progression; associations of aortic calcium and aortic calcium progression with other subclinical CVD measures, CVD risk factors, and demographics; and the prognostic significance of aortic calcium. The project has three primary specific aims: 1) to predict the cross-sectional aortic calcium burden as a function of other subclinical CVD measures and CVD risk factors; 2) to predict aortic calcium progression as a function of other subclinical CVD measures and CVD risk factors, and 3) to predict aortic calcium progression as a function of progression of selected subclinical CVD measures and CVD risk factors. The two secondary specific aims are 1) to contrast the results of the three primary specific aims for men vs. women, and for four major ethnic groups (White, Hispanic, Black, and Asian); and 2) to provide a database for future evaluation of whether aortic calcium and/or aortic calcium progression independently predict subsequent myocardial infarction, stroke, and other CVD events. This application potentially has major significance for cardiovascular health. "Total body scanning" including measurement of aortic calcium, has become a popular diagnostic tool. This application, in conjunction with the extensive subclinical and risk factor measurements available in MESA, will uniquely allow determination of the independent and incremental importance of measuring aortic calcium in CVD risk assessment.