20 YEAR CHANGES IN FITNESS & CARDIOVASCULAR DISEASE RISK

描述（由申请人提供）：虽然有氧能力的年龄相关性下降是有据可查的，但体力活动，体脂和遗传变异对变化率的影响尚不清楚。此外，关于成年早期和中期有氧能力的变化率如何影响心血管疾病危险因素的发展或亚临床和临床心血管疾病（CVD）相关终点的发生率，我们知之甚少。我们建议通过与2005年6月开始的20年CARDIA（年轻人冠状动脉风险发展）检查一起进行辅助研究来解决这些问题。我们预计，非洲裔美国人和白色男性和女性的初始队列的大约3，650（75%）的幸存成员将返回20年的考试，在这一点上，他们将是38-50岁。拟议的辅助研究的总体目标是了解身体素质、体力活动、体重和成分与脂肪分布、遗传因素之间的复杂纵向关系，以及它们对肥胖、代谢综合征和亚临床CVD发展的独立或相互作用影响。为了实现这一目标，我们建议对所有20岁的CARDIA参与者进行测量： 1.有氧运动能力，采用与CARDIA在0年级和7年级考试中使用的相同方案，通过限制性分级运动平板试验进行; 2.身体成分和脂肪分布，使用全身双能X射线吸收仪（DEXA）扫描; 3.身体活动，使用7天的加速计记录;以及 4.使用储存的DNA，在选定的与心肺功能、代谢综合征组分和对定期运动的反应相关的候选基因中的DNA序列变异。 本辅助研究的数据将与核心CARDIA检查数据相结合，以实现以下目的： a.检查身体质量和组成，脂肪分布，客观测量的身体活动和特定的遗传多态性对20年有氧能力的方差以及从青年到中年的20年时间内有氧能力与年龄相关的下降的贡献，按种族和性别分层。 B.纵向检查有氧能力对心血管疾病风险因素变化和心血管疾病相关终点（例如高血压、代谢综合征、亚临床疾病[例如冠状动脉钙]）发生率的影响。这项研究的数据应该提供信息，帮助我们更深入地了解心肺功能，身体成分和心血管疾病相关风险因素和终点之间的相互关系，并可能为更广泛的基于证据的建议提供基础。

DESCRIPTION (provided by applicant): Although an age-related decline in aerobic capacity is well documented, the impact of physical activity, body fat, and genetic variation on the rate of change is not well understood. In addition, little is known about how rate of change in aerobic capacity during early and middle adulthood affects the development of cardiovascular disease risk factors or the incidence of subclinical and clinical cardiovascular disease (CVD) related end-points. We propose to address these issues by conducting an ancillary study in conjunction with the Year 20 CARDIA (Coronary Artery Risk Development in Young Adults) examination, which is scheduled to take place beginning in June, 2005. We anticipate that approximately 3,650 (75%) of the surviving members of the initial cohort of African American and white men and women will return for the Year 20 exam, at which point they will be 38-50 years old. The overall goal of the proposed ancillary study is to understand the complex, longitudinal relations between physical fitness, physical activity, body mass and composition and fat distribution, and genetic factors and their independent or interactive effects on the development of obesity, the metabolic syndrome, and sub-clinical CVD. To accomplish this goal, we propose to measure, on all Year 20 CARDIA participants: 1. Aerobic capacity, by means of a symptom-limited graded exercise treadmill test, using the same protocol as that used in CARDIA at the Year 0 and Year 7 exams; 2. Body composition and fat distribution, using a whole body dual energy x-ray absorptiometery (DEXA) scan; 3. Physical activity, using 7 days of accelerometer recordings; and 4. DNA sequence variants in selected candidate genes associated with cardiorespiratory fitness, components of the metabolic syndrome, and response to regular exercise, using stored DNA. Data from this ancillary study will be combined with core CARDIA examination data to address the following aims: a. Examination of the contribution of body mass and composition, fat distribution, objectively measured physical activity and specific genetic polymorphisms to the variance in Year 20 aerobic capacity and in age-related decline in aerobic capacity over a 20-year time period from young adulthood to mid-life, stratifying by race and gender. b. Longitudinal examination of the effect of aerobic capacity on changes in cardiovascular disease risk factors and on the incidence of CVD-related endpoints (e.g. hypertension, metabolic syndrome, subclinical disease [e.g. coronary artery calcium]). Data from this study should provide information that will help us more deeply understand the interrelationships of cardiorespiratory fitness, body composition, and CVD-related risk factors and endpoints, and may provide the basis for more extensive evidence-based recommendations on the role of fitness in cardiovascular health.