Department of Psychology.
Department of Kinesiology.
Neuropsychology. 2022 Sep;36(6):505-512. doi: 10.1037/neu0000837. Epub 2022 Jun 23.
Parkinson's disease (PD) is a neurodegenerative disorder caused by disruption of dopamine-producing cells. PD is associated with motor symptoms and nonmotor symptoms including depression and cognitive impairment. Past research suggests an association between depression and cognitive impairment in PD. Physical activity may have a therapeutic effect on both depression and cognitive impairment. The present study investigates if physical activity mediates the association between depressive symptoms and cognition in a longitudinal sample of individuals with PD.
Participants include individuals newly diagnosed with PD ( = 487) enrolled in the Parkinson's Progression Marker Initiative (PPMI). Participants completed an array of neuropsychological tests over the course of 5 years, as well as questionnaires of depression and physical activity. Between-person and within-person effects of depression and cognition mediated through physical activity were analyzed using structural equation modeling.
A significant direct effect demonstrated depression was associated with worse global cognitive functioning. Furthermore, there was a significant indirect within-person effect, indicating that physical activity fully mediated the association between depression and cognition. Individuals who became more depressed over time became less physically active and subsequently experienced cognitive decline over the 5-year period.
Findings have implications for prognostic detection and/or the role of physical activity interventions to buffer effects of depression on cognitive impairment among individuals diagnosed with PD. Physical interventions may potentially be implemented among depressed persons to preserve cognitive functioning. Worsened depression early during PD may be a risk factor for inactivity and cognitive diminishment. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
帕金森病（PD）是一种由多巴胺产生细胞破坏引起的神经退行性疾病。PD 与运动症状和非运动症状相关，包括抑郁和认知障碍。过去的研究表明 PD 中抑郁和认知障碍之间存在关联。身体活动可能对抑郁和认知障碍都有治疗作用。本研究调查了在 PD 的纵向样本中，身体活动是否在抑郁症状和认知之间的关联中起中介作用。
参与者包括新诊断为 PD（n=487）的个体，他们参加了帕金森进展标志物倡议（PPMI）。参与者在 5 年内完成了一系列神经心理学测试，以及抑郁和身体活动问卷。使用结构方程模型分析了抑郁和认知通过身体活动的个体间和个体内效应。
一项显著的直接效应表明，抑郁与整体认知功能下降有关。此外，还有一个显著的个体内间接效应，表明身体活动完全中介了抑郁与认知之间的关联。随着时间的推移变得更加抑郁的个体变得不那么活跃，随后在 5 年内经历了认知能力下降。
这些发现对预后检测和/或身体活动干预的作用具有意义，这些干预可以缓冲 PD 个体中抑郁对认知障碍的影响。身体干预可能会在抑郁人群中实施，以保持认知功能。PD 早期的抑郁恶化可能是不活动和认知减退的风险因素。
