Objective Physical Activity and Cardiovascular Health in Women Aged 80 and Older

描述(由申请者提供)：这个为期四年的项目的目的是确定维持老年女性心血管健康所必需的体力活动的量、强度和模式。加速计将被用来表征体力活动的数量和模式。在8000名80岁及以上的WHI参与者中，我们将：1)确定通过加速计测量的体力活动总量(轻度、中度和剧烈)与心血管疾病发生率和总死亡率的关系；2)确定中等强度到剧烈强度的体力活动(MVPA)和久坐时间与心血管疾病发生率和总死亡率的关系；2.1)进行一项校准研究，旨在确定80岁及以上女性的加速度阈值，以区分久坐与轻度活动和轻度活动与中度至剧烈活动，以便使目标2与老年女性直接相关；3)比较加速度计测量的体力活动和久坐时间以及自我报告的MVPA和久坐时间与心血管事件发生率和总死亡率之间的相关性的大小和独立性；以及4)确定体力活动总量、MVPA和久坐时间与跌倒相关伤害的比率和任何伤害的总体风险的相关性。为了实现这些目标，将在全国范围内对最初在1993-1997年间参加妇女健康倡议(WHI)的80岁及以上的妇女进行8000次面对面的访问。参与者将佩戴加速度计7天，完成一份包含Champs和WHI体力活动量表以及Falls疗效量表的问卷，并至少跟踪2015年(3-4年)以确定研究结果。在校准研究中，两个WHI诊所将招募200名妇女参加诊所访问，使用间接量热法测量各种活动期间的能量消耗。这一证据对于制定基于证据的体力活动指南至关重要，这些指南与美国和世界各地日益增长的老年女性有关。

DESCRIPTION (provided by applicant): The purpose of this four year project is to determine how much, how vigorous and what patterns of physical activity are necessary to maintain cardiovascular health among older women. Accelerometers will be used to characterize the amounts and patterns of physical activity. In a cohort of 8000 WHI participants aged 80 and older we will: 1) Determine the association of total volume of physical activity (light, moderate and vigorous) as measured by accelerometry with rates of incident CVD and total mortality; 2) Determine the associations of moderate-to-vigorous-intensity physical activity (MVPA) and sedentary time with rates of incident CVD and total mortality; 2.1) Conduct a calibration study designed to determine accelerometry thresholds for women aged 80 and older that distinguish sedentary from light activity and light activity from moderate to vigorous activity in order to make Aim 2 directly relevant to older women; 3) Compare the magnitude and independence of associations between accelerometer measures of physical activity and sedentary time, and self-reported measures of MVPA and sedentary time, with rates of incident CVD and total mortality; and 4) Determine associations of total volume of physical activity, MVPA and sedentary time with rates of fall-related injuries and overall risk for any injury. To accomplish these aims, 8,000 face-to-face visits will be conducted nationwide among women aged 80 and older from the Women's Health Initiative (WHI) who were originally enrolled between 1993-1997. Participants will wear an accelerometer for 7 days, complete a questionnaire containing the CHAMPS and WHI physical activity scales, and the Falls Efficacy Scale, and be followed through at least 2015 (3-4 years) to ascertain study outcomes. For the calibration study, two WHI clinics will recruit 200 women for participation in a clinic visit to measure energy expenditure during various activities using indirect calorimetry. This evidence is crucial for formulating evidence-based physical activity guidelines that pertain to the growing population of older women in the US and worldwide.