Keenan Research Centre for Biomedical Research (WQ, TAS, NWC, DGM, JJB, CEF), Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto; the Institute of Medical Sciences (WQ, TAS, TKR, CEF), University of Toronto, Toronto.
Keenan Research Centre for Biomedical Research (WQ, TAS, NWC, DGM, JJB, CEF), Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto; the Institute of Medical Sciences (WQ, TAS, TKR, CEF), University of Toronto, Toronto; the Institute of Biomaterials and Biomedical Engineering (TAS), University of Toronto, Toronto; the Department of Surgery (TAS), Division of Neurosurgery, Faculty of Medicine, University of Toronto, Toronto; the Division of Neurosurgery (TAS), St. Michael's Hospital, Toronto.
Am J Geriatr Psychiatry. 2019 May;27(5):490-498. doi: 10.1016/j.jagp.2018.09.016. Epub 2018 Oct 2.
Delusions affect approximately a third of Alzheimer disease (AD) patients and are associated with poor outcomes. Previous studies investigating the neuroanatomic correlates of delusions have yet to reach a consensus, with findings of reduced volume across all lobes, particularly in frontal regions. The current study examined the gray matter (GM) differences associated with delusions in AD.
Using voxel-based morphometry, we assessed GM in 23 AD patients who developed delusions (AD+D) and 36 comparable AD patients who did not (AD-D) at baseline and follow-up. Analysis of variance was used to identify consistent differences between AD+D and AD-D patients across time points (main effect of group), consistent changes from baseline to follow-up (main effect of time), and differential changes between AD+D and AD-D over time (interaction of group and time). All data were obtained from the National Alzheimer's Coordinating Center database.
The AD+D group had consistently lower frontal GM volume, although both groups showed decreased GM in frontotemporal brain regions over time. An interaction was observed between delusions and longitudinal change, with AD+D patients having significantly elevated GM in predominantly temporal areas at baseline assessment, becoming significantly lower than the AD-D group at follow-up.
These findings suggest that, there are specific volumetric markers that distinguish patients with delusions from those without, before, and after the onset of delusions. Specifically, the decline of GM in temporal areas that had elevated levels prior to the onset of delusions may be involved in the manifestation of delusions.
大约三分之一的阿尔茨海默病（AD）患者存在妄想，且这些妄想与不良结局相关。既往研究对妄想的神经解剖学相关性进行了探讨，但尚未达成共识，结果显示所有脑叶的体积均减少，尤其是额叶区域。本研究旨在探讨 AD 患者出现妄想时的灰质（GM）差异。
采用基于体素的形态测量学方法，对基线和随访时出现妄想（AD+D）的 23 例 AD 患者和未出现妄想（AD-D）的 36 例可比 AD 患者的 GM 进行评估。方差分析用于识别 AD+D 与 AD-D 患者在时间点之间的一致性差异（组间主要效应）、从基线到随访的一致性变化（时间主效应）以及随时间变化的 AD+D 与 AD-D 之间的差异（组间和时间的交互作用）。所有数据均来自国家阿尔茨海默病协调中心数据库。
AD+D 组的额 GM 体积始终较低，尽管两组患者的额颞叶脑区 GM 随时间逐渐减少。妄想与纵向变化之间存在交互作用，AD+D 患者在基线评估时的主要颞区 GM 水平升高，随访时明显低于 AD-D 组。
这些发现表明，在出现妄想之前、之后以及出现妄想时，存在特定的体积标记物可以区分有妄想和无妄想的患者。具体而言，在妄想出现之前 GM 水平升高的颞区的下降可能与妄想的表现有关。
