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

描述（由申请人提供）：这个为期四年的项目的目的是确定老年妇女维持心血管健康所需要的体力活动的数量、强度和模式。加速度计将用于描述身体活动的数量和模式。在8000名年龄在80岁及以上的WHI参与者队列中，我们将：1)确定通过加速度计测量的身体活动总量（轻度、中度和剧烈）与心血管疾病发病率和总死亡率之间的关系；2)确定中等至高强度体力活动（MVPA）和久坐时间与心血管疾病发病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测量阈值，以区分久坐与轻度活动以及轻度活动与中度至剧烈活动，从而使Aim 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，与心血管疾病发病率和总死亡率之间的相关性的大小和独立性；4)确定身体活动总量、MVPA和久坐时间与跌倒相关损伤率和任何损伤的总体风险之间的关系。为了实现这些目标，将在全国范围内对最初在1993-1997年期间参加妇女健康倡议（WHI）的80岁及以上妇女进行8 000次面对面访问。参与者将佩戴加速度计7天，完成一份包含CHAMPS和WHI身体活动量表以及Falls功效量表的问卷，并至少随访至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名妇女参加门诊访问，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育活动指南至关重要，这些指南适用于美国和世界范围内不断增长的老年妇女人口。

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.