Abstract

Background:

Gait analysis with accelerometers is a relatively inexpensive and easy to use method to potentially support clinical diagnoses of Alzheimer’s disease and other dementias. It is not clear, however, which gait features are most informative and how these measures relate to Alzheimer’s disease pathology.

Objective:

In this study, we tested if calculated features of gait 1) differ between cognitively normal subjects (CN), mild cognitive impairment (MCI) patients, and dementia patients, 2) are correlated with cerebrospinal fluid (CSF) biomarkers related to Alzheimer’s disease, and 3) predict cognitive decline.

Methods:

Gait was measured using tri-axial accelerometers attached to the fifth lumbar vertebra (L5) in 58 CN, 58 MCI, and 26 dementia participants, while performing a walk and dual task. Ten gait features were calculated from the vertical L5 accelerations, following principal component analysis clustered in four domains, namely pace, rhythm, time variability, and length variability. Cognitive decline over time was measured using MMSE, and CSF biomarkers were available in a sub-group.

Results:

Linear mixed models showed that dementia patients had lower pace scores than MCI patients and CN subjects (p < 0.05). In addition, we found associations between the rhythm domain and CSF-tau, especially in the dual task. Gait was not associated with CSF Aβ₄₂ levels and cognitive decline over time as measured with the MMSE.

Conclusion:

These findings suggest that gait—particularly measures related to pace and rhythm—are altered in dementia and have a direct link with measures of neurodegeneration.

中文翻译：

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记忆临床队列中，步态障碍与认知障碍和脑脊液Tau水平升高有关。

摘要

背景：

使用加速度计进行步态分析是一种相对便宜且易于使用的方法，可以潜在地支持阿尔茨海默氏病和其他痴呆的临床诊断。然而，尚不清楚哪些步态特征最能提供信息，以及这些措施与阿尔茨海默氏病病理学之间的关系如何。

目的：

在这项研究中，我们测试了步态的计算特征1）在认知正常受试者（CN），轻度认知障碍（MCI）和痴呆症患者之间是否存在差异，2）是否与与阿尔茨海默氏病相关的脑脊液（CSF）生物标志物相关， 3）预测认知能力下降。

方法：

在执行步行和双重任务时，使用附接到58位CN，58位MCI和26位痴呆患者的第五个腰椎（L5）的三轴加速度计测量步态。根据L5的垂直加速度计算十个步态特征，然后将主成分分析集中在四个域中，即步速，节奏，时间可变性和长度可变性。随着时间的推移，认知能力下降使用MMSE进行了测量，并且CSF生物标志物可在一个亚组中获得。

结果：

线性混合模型显示，痴呆患者的步伐分数低于MCI患者和CN受试者（p  <0.05）。此外，我们发现节奏域与CSF-tau之间存在关联，尤其是在双重任务中。步态没有与CSFAβ相关联₄₂作为与MMSE测量水平和随时间的认知下降。

结论：

这些发现表明，步态（尤其是与步速和节律有关的测量）在痴呆症中发生了变化，并与神经退行性变有直接联系。