Data_Sheet_1_Weaker Braking Force, A New Marker of Worse Gait Stability in Alzheimer Disease.PDF

Background: Braking force is a gait marker associated with gait stability. This study aimed to determine the alteration of braking force and its correlation with gait stability in Alzheimer disease (AD).
Methods: A total of 32 AD patients and 32 healthy controls (HCs) were enrolled in this study. Gait parameters (braking force, gait variability, and fall risk) in the walking tests of Free walk, Barrier, and Count backward were measured by JiBuEn® gait analysis system. Gait variability was calculated by the coefficient of variation (COV) of stride time, stance time, and swing time.
Results: The braking force of AD was significantly weaker than HCs in three walking tests (P < 0.001, P < 0.001, P = 0.007). Gait variability of AD showed significant elevation than HCs in the walking of Count backward (COVstride: P = 0.013; COVswing: P = 0.006). Fall risk of AD was significantly higher than HCs in three walking tests (P = 0.001, P = 0.001, P = 0.001). Braking force was negatively associated with fall risks in three walking tests (P < 0.001, P < 0.001, P < 0.001). There were significant negative correlations between braking force and gait variability in the walking of Free walk (COVstride: P = 0.018; COVswing: P = 0.013) and Barrier (COVstride: P = 0.002; COVswing: P = 0.001), but not Count backward (COVstride: P = 0.888; COVswing: P = 0.555).
Conclusion: Braking force was weaker in AD compared to HCs, reflecting the worse gait stability of AD. Our study suggests that weakening of braking force may be a new gait marker to indicate cognitive and motor impairment and predict fall risk in AD.

背景：制动力（braking force）是与步态稳定性相关的步态标志物。本研究旨在明确阿尔茨海默病（Alzheimer disease, AD）患者的制动力变化情况，及其与步态稳定性的相关性。
方法：本研究共纳入32例阿尔茨海默病患者与32名健康对照者（healthy controls, HCs）。采用吉布恩®（JiBuEn®）步态分析系统，对自由行走、障碍行走以及倒计数行走三种步态测试中的步态参数（制动力、步态变异性（gait variability）及跌倒风险（fall risk））进行测量。步态变异性通过步幅时间（stride time）、站立时间（stance time）与摆动时间（swing time）的变异系数（coefficient of variation, COV）进行计算。
结果：在三项步态测试中，阿尔茨海默病患者的制动力均显著弱于健康对照者（P < 0.001、P < 0.001、P = 0.007）。在倒计数行走测试中，阿尔茨海默病患者的步态变异性显著高于健康对照者（步幅时间变异系数：P = 0.013；摆动时间变异系数：P = 0.006）。三项步态测试中，阿尔茨海默病患者的跌倒风险均显著高于健康对照者（均P = 0.001）。制动力与三项步态测试中的跌倒风险均呈显著负相关（均P < 0.001）。在自由行走与障碍行走测试中，制动力与步态变异性呈显著负相关（自由行走：步幅时间变异系数P = 0.018，摆动时间变异系数P = 0.013；障碍行走：步幅时间变异系数P = 0.002，摆动时间变异系数P = 0.001），但在倒计数行走测试中未发现此类相关性（步幅时间变异系数P = 0.888，摆动时间变异系数P = 0.555）。
结论：相较于健康对照者，阿尔茨海默病患者的制动力更弱，反映出其步态稳定性更差。本研究表明，制动力减弱或可作为一项新的步态标志物，用于提示阿尔茨海默病患者的认知与运动功能损害，并预测其跌倒风险。