Hemphill Lea, Valenzuela Yenny, Luna Kenya, Szymkowicz Sarah M, Jones Jacob D
California State University San Bernardino, San Bernardino, CA, USA.
Department of Psychiatry & Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
Clin Park Relat Disord. 2023 Mar 11;8:100192. doi: 10.1016/j.prdoa.2023.100192. eCollection 2023.
Parkinson's disease (PD) is the second most common progressive neurodegenerative disorder. About 40%-50% of PD patients experience depression, making it one of the most common neuropsychiatric disturbances in PD. Cognitive deficits (e.g., difficulties with memory, attention) are an additional common complication in PD. Past studies among healthy aging individuals suggest that depression is a risk factor for cognitive decline, and the risk increases with older age. This study aims to examine the association between depressive symptoms on cognitive decline as a function of age among patients with PD. It is hypothesized that older PD patients with more severe depressive symptoms will be at greater risk of cognitive decline than their younger or less depressed counterparts.
Four hundred and eighty-seven newly diagnosed patients with PD, were assessed for depression and cognition over a five-year period. Participants completed neuropsychological tests that assessed memory, learning, attention, visuospatial functioning, processing speed, and verbal fluency. Multilevel-modeling was used to examine the longitudinal association between cognition, age, and depressive symptoms.
Our results indicated a significant three-way interaction (age X occasion X depressive symptoms) predicting language and working memory/attention performance. More specifically, detrimental associations of depressive symptoms on cognitive decline in these domains were more pronounced among older adults.
Our findings support that older PD patients with comorbid depressive symptoms experience greater cognitive decline compared to their younger counterparts. Findings suggest that older individuals with PD may be more vulnerable to neurotoxic effects of depression (e.g., neuroinflammation, HPA axis disruption), and better management of depression could potentially reduce cognitive decline and dementia risk.
帕金森病（PD）是第二常见的进行性神经退行性疾病。约40%-50%的帕金森病患者会出现抑郁，这使其成为帕金森病最常见的神经精神障碍之一。认知缺陷（如记忆、注意力方面的困难）是帕金森病另一种常见的并发症。过去针对健康老年人的研究表明，抑郁是认知衰退的一个风险因素，且风险随年龄增长而增加。本研究旨在探讨帕金森病患者中，抑郁症状与认知衰退之间随年龄变化的关联。研究假设为，与年轻或抑郁程度较轻的帕金森病患者相比，抑郁症状更严重的老年帕金森病患者认知衰退的风险更高。
487名新诊断的帕金森病患者在五年期间接受了抑郁和认知评估。参与者完成了评估记忆、学习、注意力、视觉空间功能、处理速度和语言流畅性的神经心理学测试。采用多水平模型来检验认知、年龄和抑郁症状之间的纵向关联。
我们的结果表明，存在一个显著的三向交互作用（年龄×时间点×抑郁症状），可预测语言及工作记忆/注意力表现。更具体地说，在这些领域中，抑郁症状与认知衰退的有害关联在老年人中更为明显。
我们的研究结果支持，与年轻患者相比，伴有抑郁症状的老年帕金森病患者认知衰退更严重。研究结果表明，患有帕金森病的老年人可能更容易受到抑郁的神经毒性作用（如神经炎症、下丘脑-垂体-肾上腺轴功能紊乱）的影响，更好地管理抑郁可能会降低认知衰退和痴呆风险。
