Pantall Annette, Suresparan Piriya, Kapa Leanne, Morris Rosie, Yarnall Alison, Del Din Silvia, Rochester Lynn
Clinical Ageing Research Unit, Institute of Neuroscience, Newcastle University Institute of Ageing, Newcastle upon Tyne, United Kingdom.
Department of Neurology, Oregon Health and Science University, Portland, OR, United States.
Front Neurol. 2018 Dec 5;9:1044. doi: 10.3389/fneur.2018.01044. eCollection 2018.
Early features of Parkinson's disease (PD) include both motor and cognitive changes, suggesting shared common pathways. A common motor dysfunction is postural instability, a known predictor of falls, which have a major impact on quality of life. Understanding mechanisms of postural dynamics in PD and specifically how they relate to cognitive changes is essential for developing effective interventions. The aims of this study were to examine the changes that occur in postural metrics over time and explore the relationship between postural and cognitive dysfunction. The study group consisted of 35 people (66 ± 8years, 12 female, UPDRS III: 22.5 ± 9.6) diagnosed with PD who were recruited as part of the Incidence of Cognitive Impairment in Cohorts with Longitudinal Evaluation-PD Gait (ICICLE-GAIT) study. Postural and cognitive assessments were performed at 18, 36, and 54 months after enrolment. Participants stood still for 120 s, eyes open and arms by their side. Postural dynamics were measured using metrics derived from a single tri-axial accelerometer (Axivity AX3, York, UK) on the lower back. Accelerometry metrics included jerk (derivative of acceleration), root mean square, frequency, and ellipsis (acceleration area). Cognition was evaluated by neuropsychological tests including the Montreal Cognitive Assessment (MoCA) and digit span. There was a significant decrease in accelerometry parameters, greater in the anteroposterior direction, and a decline in cognitive function over time. Accelerometry metrics were positively correlated with lower cognitive function and increased geriatric depression score and negatively associated with a qualitative measure of balance confidence. In conclusion, people with PD showed reduced postural dynamics that may represent a postural safety strategy. Associations with cognitive function and depression, both symptoms that may pre-empt motor symptoms, suggest shared neural pathways. Further studies, involving neuroimaging, may determine how these postural parameters relate to underlying neural and clinical correlates.
帕金森病（PD）的早期特征包括运动和认知变化，提示存在共同的通路。一种常见的运动功能障碍是姿势不稳，这是跌倒的已知预测因素，对生活质量有重大影响。了解PD中姿势动力学的机制，特别是它们与认知变化的关系，对于制定有效的干预措施至关重要。本研究的目的是检查姿势指标随时间的变化，并探讨姿势与认知功能障碍之间的关系。研究组由35名被诊断为PD的患者组成（年龄66±8岁，女性12名，统一帕金森病评定量表第三部分[UPDRS III]评分：22.5±9.6），他们是作为帕金森病纵向评估队列中认知障碍发生率-步态研究（ICICLE-GAIT）的一部分招募的。在入组后18、36和54个月进行姿势和认知评估。参与者双脚并拢站立120秒，并保持睁眼、双臂自然下垂。使用安装在下背部的单轴三轴加速度计（Axivity AX3，英国约克）获得的指标来测量姿势动力学。加速度计指标包括加加速度（加速度的导数）、均方根、频率和椭圆面积（加速度区域）。通过包括蒙特利尔认知评估量表（MoCA）和数字广度测试在内的神经心理学测试评估认知功能。随着时间的推移，加速度计参数显著下降，前后方向下降更明显，认知功能也有所下降。加速度计指标与较低的认知功能、老年抑郁评分升高呈正相关，与平衡信心的定性测量呈负相关。总之，PD患者的姿势动力学降低，这可能代表一种姿势安全策略。与认知功能和抑郁的关联，这两种症状可能先于运动症状出现，提示存在共同的神经通路。涉及神经影像学的进一步研究可能会确定这些姿势参数与潜在神经及临床相关因素的关系。
