Beauchet Olivier, Allali Gilles, Montero-Odasso Manuel, Sejdić Ervin, Fantino Bruno, Annweiler Cédric
Division of Geriatric Medicine, Department of Neuroscience, Angers University Hospital, Angers, France.
Department of Neurology, Geneva University Hospital and University of Geneva, Geneva, Switzerland.
PLoS One. 2014 Jun 9;9(6):e99318. doi: 10.1371/journal.pone.0099318. eCollection 2014.
Decline in cognitive performance is associated with gait deterioration. Our objectives were: 1) to determine, from an original study in older community-dwellers without diagnosis of dementia, which gait parameters, among slower gait speed, higher stride time variability (STV) and Timed Up & Go test (TUG) delta time, were most strongly associated with lower performance in two cognitive domains (i.e., episodic memory and executive function); and 2) to quantitatively synthesize, with a systematic review and meta-analysis, the association between gait performance and cognitive decline (i.e., mild cognitive impairment (MCI) and dementia).
Based on a cross-sectional design, 934 older community-dwellers without dementia (mean±standard deviation, 70.3±4.9years; 52.1% female) were recruited. A score at 5 on the Short Mini-Mental State Examination defined low episodic memory performance. Low executive performance was defined by clock-drawing test errors. STV and gait speed were measured using GAITRite system. TUG delta time was calculated as the difference between the times needed to perform and to imagine the TUG. Then, a systematic Medline search was conducted in November 2013 using the Medical Subject Heading terms "Delirium," "Dementia," "Amnestic," "Cognitive disorders" combined with "Gait" OR "Gait disorders, Neurologic" and "Variability."
A total of 294 (31.5%) participants presented decline in cognitive performance. Higher STV, higher TUG delta time, and slower gait speed were associated with decline in episodic memory and executive performances (all P-values <0.001). The highest magnitude of association was found for higher STV (effect size = -0.74 [95% Confidence Interval (CI): -1.05;-0.43], among participants combining of decline in episodic memory and in executive performances). Meta-analysis underscored that higher STV represented a gait biomarker in patients with MCI (effect size = 0.48 [95% CI: 0.30;0.65]) and dementia (effect size = 1.06 [95% CI: 0.40;1.72]).
Higher STV appears to be a motor phenotype of cognitive decline.
认知功能下降与步态恶化有关。我们的目标是：1）在一项针对未诊断为痴呆的老年社区居民的原始研究中，确定在较慢的步态速度、较高的步幅时间变异性（STV）和定时起立行走测试（TUG）时间差中，哪些步态参数与两个认知领域（即情景记忆和执行功能）的较低表现最密切相关；2）通过系统评价和荟萃分析，定量综合步态表现与认知衰退（即轻度认知障碍（MCI）和痴呆）之间的关联。
基于横断面设计，招募了934名未患痴呆的老年社区居民（平均±标准差，70.3±4.9岁；52.1%为女性）。简易精神状态检查表得分为5分定义为情景记忆表现低。执行功能低下由画钟试验错误定义。使用GAITRite系统测量STV和步态速度。TUG时间差计算为执行TUG所需时间与想象TUG所需时间之间的差值。然后，2013年11月使用医学主题词“谵妄”、“痴呆”、“遗忘”、“认知障碍”与“步态”或“步态障碍，神经学”和“变异性”进行了系统的Medline检索。
共有294名（31.5%）参与者出现认知功能下降。较高的STV、较高的TUG时间差和较慢的步态速度与情景记忆和执行功能下降相关（所有P值<0.001）。在情景记忆和执行功能均下降的参与者中，发现STV升高的关联程度最高（效应大小=-0.74[95%置信区间（CI）：-1.05；-0.43]）。荟萃分析强调，较高的STV代表MCI患者（效应大小=0.48[95%CI：0.30；0.65]）和痴呆患者（效应大小=1.06[95%CI：0.40；1.72]）的一种步态生物标志物。
较高的STV似乎是认知衰退的一种运动表型。
