The Associations of Mid- and Late-Life Physical Activity on Falls in a Large Prospective Study of Older Adults

 描述（由申请人提供）：随着年龄≥ 65岁的美国成年人的预计快速增长，福尔斯跌倒和跌倒相关伤害的数量以及相关费用将继续增加。基于几十年的研究，主要是随机对照试验，体力活动已被确定为一个重要的一级预防策略福尔斯。然而，以前的干预措施的具体身体活动组成部分有所不同，大多数针对身体活动建议的一般健康益处，而不是预防跌倒。此外，根据客观的身体活动措施，不到3%的美国老年人符合目前的建议。这是一个重要的脱节，值得进一步研究。此外，一旦发生跌倒，相关的体力活动下降可能会增加后续福尔斯跌倒的风险。虽然研究已经确定了跌倒后的主要生活变化，但没有人检查跌倒事件后身体活动的变化程度。纵向研究设计提供了必要的灵活性，以检查这些重要的研究差距。为了解决这些差距，我们将进行一项前瞻性队列研究，以检查身体活动和福尔斯的双向关联，包括身体活动（暴露）的客观测量与福尔斯和伤害性福尔斯风险（结局）之间的剂量-反应关系，以及跌倒事件（暴露）对后续身体活动（结局）的影响。参与者将从现有的社区动脉粥样硬化风险（ARIC）研究中抽取，他们居住在社区或独立生活在老年人住房内，可以走动，没有重度/中度认知障碍。该辅助研究将与拟定的父ARIC研究检查访视同时进行。我们将前瞻性地收集：（1）在基线和每12个月（3个时间点）使用加速度计对身体活动进行客观测量，以及（2）在基线和每6个月（5个时间点）的福尔斯和损伤性福尔斯的数量。 24个月期间，在这一大型（n= 3，200），不同队列的黑人和白色老年人年龄为71-93岁。我们还将使用30年的历史ARIC数据来研究中年体力活动对晚年跌倒风险的影响。为实现这些目标，我们提出以下三个具体目标：（1）确定身体活动客观指标类别之间的剂量-反应关系（总活动量和强度类别的活动量）和福尔斯和损伤性福尔斯的风险，并检查这些关联是否因性别、年龄、和比赛（2）评估跌倒事件对随后的身体活动水平的影响（总活动量和强度类别的活动量），同时考虑害怕跌倒的修正效应;以及（3）检查从中晚睡开始的身体活动轨迹与以后生活中的身体活动、身体功能和跌倒风险的关联。这项拟议的工作具有重要的公共卫生意义，因为它解决了文献中与降低跌倒风险的特定活动剂量有关的空白，福尔斯对随后的身体健康的影响， 活动，以及中晚期身体活动对晚年跌倒风险的影响。

 DESCRIPTION (provided by applicant): With the projected rapid growth of U.S. adults aged = 65 years, the numbers of falls and fall-related injuries, and the associated costs, will continue t escalate. Based on several decades of research from primarily randomized controlled trials, physical activity has been identified as an important primary prevention strategy for falls. Yet, the specific physical activity components of previous interventions have varied, with most targeting physical activity recommendations for general health benefit, rather than for fall prevention. Further, based on objective physical activity measures, less than 3% of older U.S. adults meet current recommendations. This is an important disconnect that warrants further examination. Also, once a fall occurs, associated physical activity declines may increase risk for subsequent falls. While studies have identified major life changes post falling, none have examined the degree to which physical activity changes after a fall event. The longitudinal study design provides the necessary flexibility to examine these important research gaps. To address these gaps we will conduct a prospective cohort study to examine the bi-directional associations of physical activity and falls, including the dose-response relationship between of objective measures of physical activity (exposure) and risk of falls and injurious falls (outcomes) as well as the impact of fall event(s) (exposure) on subsequent physical activity (outcome). Participants will be drawn from the existing Atherosclerosis Risk in Communities (ARIC) Study who are community dwelling or living independently within senior housing, ambulatory, and without severe/moderate cognitive impairment. This ancillary study will be conducted concurrently with a proposed Parent ARIC Study exam visit. We will prospectively collect: (1) objective measures of physical activity using accelerometers at baseline and every 12 months (3 time points), and (2) the number of falls and injurious falls at baseline and every six months (5 time points) over a 24 month period in this large (n=3,200), diverse cohort of black and white older adults aged 71-93 years. We will also use 30 years of historical ARIC data to examine the impact of mid-life physical activity on fall risk in later-life. To accomplish these goals, we propose the following three specific aims: (1) Determine the dose-response associations between categories of objective measures of physical activity (total activity volume and volume by intensity categories) and risk of falls and injurious falls, and examine if these associations vary by sex, age, and race (2) evaluate the impact of a fall event(s) on subsequent physical activity levels (total activity volume and volume by intensity categories) while considering the modifying effects of fear of falling; and (3) examine the association of trajectories of physical activity from mid- and late-lie with physical activity, physical function and fall risk in later life. This proposed work has important public health significance as it addresses gaps in the literature pertaining to the specific activity dose that confers fall-risk reduction, the impact of falls on subsequent physical activity, and mid- and late-life physical activity on fall risk in later life.