Lacey Colleen, Ohlhauser Lisa, Gawryluk Jodie Reanna
Psychology Department, University of Victoria, Victoria, BC, Canada.
The Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
Front Neurol. 2019 Aug 13;10:884. doi: 10.3389/fneur.2019.00884. eCollection 2019.
Clarifying the neuropathology of depression as a symptom of Parkinson's disease (PD) has been the goal of recent neuroimaging studies; however, results have been conflicting and lack replication. The purpose of the current study was to replicate recent methods that have used diffusion tensor imaging (DTI) to compare individuals with PD with and without depression and to extend previous findings to allow for a better understanding of the results. Thirty-seven participants with PD were retrieved from the Parkinson's Progression Marker's Initiative (PPMI) and were separated into a depressed PD group (dPD) or a non-depressed PD group (ndPD). Groups were determined based on scores on the Geriatric Depression Scale Short Form (GDS-15). Initially, a replicated cut off score of ≥ 5 for dPD and <5 for ndPD was applied. To better understand the results, we secondarily applied a more extreme group analysis with ≥ 9 for dPD and 0 for ndPD. White matter integrity between groups was compared between groups using tract-based spatial statistics. The current study did not reveal significant differences in white matter microstructure between dPD and ndPD groups at the whole brain level or in specific regions of interest. The extreme group results were consistent. These findings did not replicate previous work that found reduced white matter integrity in limbic prefrontal regions in dPD relative to ndPD. The current study highlights the need for more replications of neuroimaging research.
阐明作为帕金森病（PD）一种症状的抑郁症的神经病理学一直是近期神经影像学研究的目标；然而，结果相互矛盾且缺乏重复性。本研究的目的是重复近期使用扩散张量成像（DTI）比较患有和未患有抑郁症的PD患者的方法，并扩展先前的研究结果，以便更好地理解这些结果。从帕金森病进展标志物倡议（PPMI）中选取了37名PD患者，并将其分为抑郁型PD组（dPD）或非抑郁型PD组（ndPD）。根据老年抑郁量表简表（GDS - 15）的得分来确定分组。最初，应用dPD组≥5分和ndPD组<5分的重复临界值。为了更好地理解结果，我们其次应用了一种更极端的分组分析，dPD组≥9分，ndPD组为0分。使用基于体素的空间统计学方法比较两组之间的白质完整性。本研究未发现dPD组和ndPD组在全脑水平或特定感兴趣区域的白质微观结构存在显著差异。极端分组结果是一致的。这些发现并未重复先前的研究工作，即先前研究发现dPD组相对于ndPD组边缘前额叶区域的白质完整性降低。本研究强调了神经影像学研究需要更多重复性研究。
