20 YEAR CHANGES IN FITNESS & CARDIOVASCULAR DISEASE RISK

描述(由申请人提供)：尽管与年龄相关的有氧能力下降有很好的记录，但体力活动、体脂和遗传变异对变化率的影响还没有很好的理解。此外，关于成年早期和中期有氧能力的变化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，人们知之甚少。我们建议在计划于2005年6月开始的CARDIA(青年冠状动脉风险发展)考试的同时进行一项辅助研究，以解决这些问题。我们预计，在最初的非裔美国人和白人男性和女性队列中，大约3650名幸存成员(75%)将返回参加20年考试，届时他们将达到38-50岁。拟议的辅助研究的总体目标是了解身体健康、身体活动、身体质量和组成与脂肪分布之间的复杂、纵向关系，以及遗传因素及其对肥胖、代谢综合征和亚临床心血管疾病发展的独立或交互影响。为了实现这一目标，我们建议对CARDIA第20年的所有参与者进行衡量： 1.有氧能力，通过症状受限的分级运动跑步机测试，使用与CARDIA在0年级和7年级考试中使用的相同方案； 2.身体成分和脂肪分布，采用全身双能X射线吸收法(DEXA)扫描； 3.体力活动，使用7天的加速度计记录；以及 4.使用存储的DNA，与心肺功能、代谢综合征的成分和对常规运动的反应相关的选定候选基因中的DNA序列变异。 这项辅助研究的数据将与CARDIA核心检查数据相结合，以实现以下目标： A.按种族和性别分层，检查体重和组成、脂肪分布、客观测量的体力活动和特定的遗传多态对20年有氧能力和与年龄有关的有氧能力下降的影响，按种族和性别分层。 B.纵向检查有氧能力对心血管疾病危险因素变化和心血管疾病相关终点(如高血压、代谢综合征、亚临床疾病[如冠状动脉钙化])发生率的影响。这项研究的数据将有助于我们更深入地了解心肺健康、身体成分和心血管疾病相关危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，说明健身在心血管健康中的作用。

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.