Gait instability in the elderly with increased fall risk

描述(由申请人提供)：跌倒是老年人发病和死亡的主要原因。虽然步态和灵活性通常被认为是过度学习和自动功能，但最近的发现强调了认知功能在跌倒风险和步态可变性中的潜在重要性。初步工作表明，特定的较高水平的认知功能影响步态可变性和跌倒风险，但认知功能和步态可变性之间的关系尚未得到很好的研究。例如，目前尚不清楚特发性老年跌倒者在行走时执行次要任务时是否或为什么会增加步幅对步幅的变异性。将进行两项关于认知功能、步态可变性和跌倒风险的研究。这些对认知功能和步态多方面的研究，特别是在双重任务条件下，应该证明步态，特别是步态的可变性，与执行功能和注意力有关，并可能依赖于执行功能和注意力。具体地说，我们将检验以下假设：1)执行功能和注意力影响老年人的步态可变性和跌倒风险。利用计算机化的神经心理测试，我们的目标是首次识别认知功能的特定组成部分，这些认知功能调节社区生活的老年人(跌倒和不跌倒的人)和健康的年轻人的步态可变性、摔倒风险和双重任务步态能力。2)步态变异性随时间的变化与认知功能的变化相平行。将对居住在社区的老年人进行一项为期三年的前瞻性研究，以确定认知功能随时间的变化与步态和跌倒风险的变化相关，并确定认知功能和步态变异性的评估是否能增强对未来跌倒者的前瞻性识别。这项前瞻性研究将使我们能够记录老年人通常衰退的两种生理系统的自然历史，回答有关老年人步态和跌倒风险的性质及其对认知功能的依赖的关键问题，并为治疗步态障碍和降低跌倒风险的新方法奠定基础。

DESCRIPTION (provided by applicant): Falls are a leading cause of morbidity and mortality among older adults. Although gait and mobility are generally considered over-learned and automatic functions, recent findings highlight the potential importance of cognitive function in fall risk and gait variability. Preliminary work suggests that specifically higher-level cognitive function influences gait variability and fall risk, but the relationships between cognitive function and gait variability have not been well-studied. For example, it is not clear if or why idiopathic elderly fallers increase stride-to-stride variability when they perform a secondary task while walking. Two studies of cognitive function, gait variability, and fall risk will be performed. These studies of multiple aspects of cognitive function and gait, especially under "dual tasking" conditions, should demonstrate that gait, in particular gait variability, is related to and may rely on executive function and attention. Specifically, we will test the following hypotheses: 1) Executive function and attention influence gait variability and fall risk in older adult, "idiopathic" fallers. Using computerized neuropsychological testing, we aim to identify, for the first time, the specific components of cognitive function that modulate gait variability, fall risk, and dual-tasking gait abilities among community living older adults (fallers and non-fallers) and healthy young adults. 2) Changes over time in gait variability parallel changes in cognitive function. A three-year prospective study of community living older adults will be performed to identify which changes in cognitive function over time are associated with changes in gait and fall risk, and to determine whether the assessment of cognitive function and gait variability enhances the prospective identification of future fallers. This prospective study will allow us to document the natural history of two physiologic systems that commonly decline in older adults, to answer key questions regarding the nature of gait and fall risk in older adults and their dependence on cognitive function, and to set the stage for for new ways of treating gait disturbances and reducing fall risk.