Physical Activity and Aging Lab, UNESP, Univ Estadual Paulista, Institute of Biosciences, Rio Claro, São Paulo, Brazil.
Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2012 Sep;19(5):644-56. doi: 10.1080/13825585.2012.661398. Epub 2012 Feb 23.
The decline in frontal cognitive functions contributes to alterations of gait and increases the risk of falls in patients with dementia, a category which included Alzheimer's disease (AD). The objective of the present study was to compare the gait parameters and the risk of falls among patients at different stages of AD, and to relate these variables with cognitive functions. This is a cross-sectional study with 23 patients with mild and moderate AD. The Clinical Dementia Rating was used to classify the dementia severity. The kinematic parameters of gait (cadence, stride length, and stride speed) were analyzed under two conditions: (a) single task (free gait) and (b) dual task (walking and counting down). The risk of falls was evaluated using the Timed Up-and-Go test. The frontal cognitive functions were evaluated using the Frontal Assessment Battery (FAB), the Clock Drawing Test (CDT) and the Symbol Search Subtest. The patients who were at the moderate stage suffered reduced performance in their stride length and stride speed in the single task and had made more counting errors in the dual task and still had a higher fall risk. Both the mild and the moderate patients exhibited significant decreases in stride length, stride speed and cadence in the dual task. Was detected a significant correlation between CDT, FAB, and stride speed in the dual task condition. We also found a significant correlation between subtest Similarities, FAB and cadence in the dual task condition. The dual task produced changes in the kinematic parameters of gait for the mild and moderate AD patients and the gait alterations are related to frontal cognitive functions, particularly executive functions.
认知功能的下降导致痴呆患者（包括阿尔茨海默病）步态改变和跌倒风险增加。本研究的目的是比较不同阶段 AD 患者的步态参数和跌倒风险，并将这些变量与认知功能相关联。这是一项横断面研究，纳入了 23 例轻度和中度 AD 患者。采用临床痴呆评定量表（CDR）对痴呆严重程度进行分类。在两种情况下（a）单任务（自由行走）和（b）双任务（行走和倒数计数）下分析步态的运动学参数（步频、步长和步速）。采用计时起立行走测试（TUGT）评估跌倒风险。采用额叶评估量表（FAB）、画钟试验（CDT）和符号搜索测验评估额叶认知功能。处于中度阶段的患者在单任务时步长和步速下降，在双任务时计数错误更多，且跌倒风险更高。轻度和中度患者在双任务时步长、步速和步频均显著下降。在双任务条件下，CDT、FAB 和步速之间存在显著相关性。我们还发现双任务条件下相似性亚测验、FAB 和步频之间存在显著相关性。双任务会改变轻度和中度 AD 患者的步态运动学参数，步态改变与额叶认知功能，特别是执行功能有关。
