From Vita-Salute San Raffaele University (G.T., C.B., D.P.); In Vivo Human Molecular and Structural Neuroimaging Unit, Division of Neuroscience (G.T., C.B., L.P., D.P.), IRCCS San Raffaele Scientific Institute; Nuclear Medicine Unit (E.G.V., L.P., D.P.), San Raffaele Hospital; Unit of Neurology and Neuropathology (P.T.), Fondazione IRCCS Istituto Neurologico Carlo Besta (C.M., G.F., F.T.), Milan; Laboratory of Neuropsychiatry (V.C., N.B., F.P., G.S.), IRCCS Santa Lucia Foundation, Rome; IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli (G.B.F.), Brescia, Italy; Memory Clinic and LANVIE-Laboratory of Neuroimaging of Aging (G.B.F.), University Hospitals and University of Geneva, Switzerland; ICoN (S.F.C.), Scuola Universitaria Superiore IUSS Pavia; and IRCCS Mondino Foundation (S.F.C.), Pavia, Italy.
Neurology. 2022 Jul 18;99(3):e258-e269. doi: 10.1212/WNL.0000000000200351.
This was a multicenter study aimed at investigating the characteristics of cognitive decline, neuropsychiatric symptoms, and brain imaging in individuals with subjective cognitive decline (SCD) and subtle cognitive decline (pre-mild cognitive impairment [pre-MCI]).
Data were obtained from the Network-AD project (NET-2011-02346784). The included participants underwent baseline cognitive and neurobehavioral evaluation, FDG-PET, and amyloid PET. We used principal component analysis (PCA) to identify independent neuropsychological and neuropsychiatric dimensions and their association with brain metabolism.
A total of 105 participants (SCD = 49, pre-MCI = 56) were included. FDG-PET was normal in 45% of participants and revealed brain hypometabolism in 55%, with a frontal-like pattern as the most frequent finding (28%). Neuropsychiatric symptoms emerging from the Neuropsychiatric Inventory and the Starkstein Apathy Scale were highly prevalent in the whole sample (78%). An abnormal amyloid load was detected in the 18% of the participants who underwent amyloid PET (n = 60). PCA resulted in 3 neuropsychological factors: (1) executive/visuomotor, correlating with hypometabolism in frontal and occipital cortices and basal ganglia; (2) memory, correlating with hypometabolism in temporoparietal regions; and (3) visuospatial/constructional, correlating with hypometabolism in frontoparietal cortices. Two factors emerged from the neuropsychiatric PCA: (1) affective, correlating with hypometabolism in orbitofrontal and cingulate cortex and insula; (2) hyperactive/psychotic, correlating with hypometabolism in frontal, temporal, and parietal regions.
FDG-PET evidence suggests either normal brain function or different patterns of brain hypometabolism in SCD and pre-MCI. These results indicate that SCD and pre-MCI represent heterogeneous populations. Different neuropsychological and neuropsychiatric profiles emerged, which correlated with neuronal dysfunction in specific brain regions. Long-term follow-up studies are needed to assess the risk of progression to dementia in these conditions.
本研究为多中心研究，旨在探究主观认知下降（SCD）和轻度认知障碍前期（pre-MCI）患者认知下降、神经精神症状和脑影像学的特点。
研究数据来自 AD 网络项目（NET-2011-02346784）。纳入的参与者接受了基线认知和神经行为评估、FDG-PET 和淀粉样蛋白 PET。我们使用主成分分析（PCA）来识别独立的神经心理学和神经精神维度及其与脑代谢的关系。
共纳入 105 名参与者（SCD=49 例，pre-MCI=56 例）。45%的参与者 FDG-PET 正常，55%的参与者存在脑代谢低下，最常见的表现为额状模式（28%）。神经精神症状量表（Neuropsychiatric Inventory 和 Starkstein 淡漠量表）显示，整个样本中神经精神症状的发生率很高（78%）。18%接受淀粉样蛋白 PET 的参与者（n=60）存在异常淀粉样蛋白负荷。PCA 得到 3 个神经心理学因子：（1）执行/视运动，与额皮质、顶叶皮质和基底节的代谢低下相关；（2）记忆，与颞顶叶区域的代谢低下相关；（3）视空间/结构性，与额顶叶皮质的代谢低下相关。神经精神 PCA 得出 2 个因素：（1）情感，与眶额皮质、扣带回皮质和岛叶的代谢低下相关；（2）多动/精神病性，与额、颞和顶叶区域的代谢低下相关。
FDG-PET 证据表明，SCD 和 pre-MCI 患者的脑功能可能正常，也可能存在不同的脑代谢低下模式。这些结果表明，SCD 和 pre-MCI 代表异质人群。出现了不同的神经心理学和神经精神特征，与特定脑区的神经元功能障碍相关。需要进行长期随访研究来评估这些情况下向痴呆进展的风险。
