Department of Life Sciences, Brunel University London, London, UK.
Department of Neuroscience, University of Sheffield, Sheffield, UK.
Eur Arch Psychiatry Clin Neurosci. 2023 Feb;273(1):229-241. doi: 10.1007/s00406-022-01417-5. Epub 2022 May 13.
People with Alzheimer's disease (AD) and delusions have worse quality of life and prognosis. However, early markers of delusions have not been identified yet. The present study investigated whether there are any detectable differences in grey matter (GM) volume and cognitive changes in the year before symptom onset between patients with AD who did and did not develop delusions. Two matched samples of AD patients, 63 who did (PT-D) and 63 who did not develop delusions (PT-ND) over 1 year, were identified from the Alzheimer's Disease Neuroimaging Initiative database. The Neuropsychiatric Inventory (NPI) was used to assess the presence of delusions. Sixty-three additional matched healthy controls (HC) were selected. Repeated-measures ANCOVA models were used to investigate group-by-time effects on the volume of selected GM regions of interest and on cognitive performance. No neurocognitive differences were observed between patient groups prior to symptom onset. Greater episodic memory decline and GM loss in bilateral caudate nuclei, medio-temporal and midline cingulo-parietal regions were found in the PT-D compared with the PT-ND group. A pattern of faster GM loss in brain areas typically affected by AD and in cortical and subcortical targets of dopaminergic pathways, paralleled by worsening of episodic memory and behavioural symptoms, may explain the emergence of delusions in patients with AD.
患有阿尔茨海默病（AD）和妄想症的人生活质量和预后更差。然而，目前尚未确定妄想症的早期标志物。本研究旨在探讨在症状出现前一年，是否存在 AD 患者出现和不出现妄想症之间的可检测到的灰质（GM）体积和认知变化差异。从阿尔茨海默病神经影像学倡议数据库中确定了两组匹配的 AD 患者，即 63 名出现（PT-D）和 63 名未出现（PT-ND）妄想症的患者。使用神经精神疾病问卷（NPI）评估妄想症的存在。选择了另外 63 名匹配的健康对照组（HC）。使用重复测量方差分析模型来研究组间时间对选定 GM 感兴趣区域的体积和认知表现的影响。在症状出现之前，患者组之间没有观察到神经认知差异。与 PT-ND 组相比，PT-D 组在双侧尾状核、中颞叶和中线扣带回-顶叶区域观察到更大的情景记忆下降和 GM 损失。在 AD 患者中，出现妄想症的原因可能是大脑区域的 GM 更快丢失，这些区域通常受 AD 影响，并且是多巴胺能通路的皮质和皮质下靶区，同时情景记忆和行为症状恶化。
