Longitudinal Study on Dual-Tasking Effects on Gait: Cognitive Change Predicts Gait Variance in the Elderly
Longitudinal Study on Dual-Tasking Effects on Gait: Cognitive Change Predicts Gait Variance in the Elderly
复制标题
DOI：
10.1371/journal.pone.0099436
复制
发表时间：
2014-06-06
期刊：
影响因子：
3.7
通讯作者：
Keller, Jeffrey N.
中科院分区：
文献类型：
--
作者：
MacAulay, Rebecca K.;Brouillette, Robert M.;Keller, Jeffrey N.
神经心理学的能力已经发现，解释了很大比例的差异，在客观措施的步行步态，预测痴呆症和下降的老年人。然而，到目前为止，几乎没有研究这些神经心理过程和步行步态随时间的变化之间的相互作用。据我们所知，本研究是第一个调查的神经认知测试性能和步态步时间在两个时间点在一年跨度的个体内的变化。通过重复测量t检验分析了440名在第一年被认为认知正常的老年人的神经心理学测试分数，以评估第二年认知能力的下降。这440人中有34人在第二年的神经心理学测试表现显着下降;而“非下降者”显示出记忆力，工作记忆，注意力/处理速度测试表现有所改善。在两个时间点的神经心理学测试分数也被提交到因子分析，用于数据简化目的和评估随时间推移的因子稳定性。第一年的结果产生了三个因素的解决方案：语言/记忆，执行注意力/处理速度和工作记忆。第二年的测试成绩也产生了一个三因素的解决方案（工作记忆，语言/执行注意力/处理速度和记忆）。值得注意的是，在第二年，语言测量加载在执行注意力/处理速度上，而不是记忆因素上。分层多元回归显示，执行注意/处理速度和性别显着预测方差双任务步骤时间在两个时间点。值得注意的是，在“下降者”中，神经心理学特征对步态变化的贡献程度在第二年显著增加。总之，本研究提供了纵向证据的动态关系的个体内认知变化和它的影响双任务步态步时间。这些结果还表明，重复给药未能显示出改善的测试表现（特别是记忆测试）可能被证明是早期认知下降的有用指标。
Neuropsychological abilities have found to explain a large proportion of variance in objective measures of walking gait that predict both dementia and falling within the elderly. However, to this date there has been little research on the interplay between changes in these neuropsychological processes and walking gait overtime. To our knowledge, the present study is the first to investigate intra-individual changes in neurocognitive test performance and gait step time at two-time points across a one-year span. Neuropsychological test scores from 440 elderly individuals deemed cognitively normal at Year One were analyzed via repeated measures t-tests to assess for decline in cognitive performance at Year Two. 34 of these 440 individuals neuropsychological test performance significantly declined at Year Two; whereas the "non-decliners" displayed improved memory, working memory, attention/processing speed test performance. Neuropsychological test scores were also submitted to factor analysis at both time points for data reduction purposes and to assess the factor stability overtime. Results at Year One yielded a three-factor solution: Language/Memory, Executive Attention/Processing Speed, and Working Memory. Year Two's test scores also generated a three-factor solution (Working Memory, Language/Executive Attention/Processing Speed, and Memory). Notably, language measures loaded on Executive Attention/Processing Speed rather than on the Memory factor at Year Two. Hierarchal multiple regression revealed that both Executive Attention/Processing Speed and sex significantly predicted variance in dual task step time at both time points. Remarkably, in the "decliners", the magnitude of the contribution of the neuropsychological characteristics to gait variance significantly increased at Year Two. In summary, this study provides longitudinal evidence of the dynamic relationship between intra-individual cognitive change and its influence on dual task gait step time. These results also indicate that the failure to show improved test performance (particularly, on memory tests) with repeated administrations might prove to be useful of indicator of early cognitive decline.