Yang Caishui, Sun Xuan, Tao Wuhai, Li Xin, Zhang Junying, Jia Jianjun, Chen Kewei, Zhang Zhanjun
State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal UniversityBeijing, China; Beijing Aging Brain Rejuvenation Initiative Centre, Beijing Normal UniversityBeijing, China.
Department of Geriatric Neurology, Chinese PLA General Hospital Beijing, China.
Front Aging Neurosci. 2017 Jan 10;8:332. doi: 10.3389/fnagi.2016.00332. eCollection 2016.
It is well known that there is a wide range of different pathological stages related to Alzheimer's disease (AD) among patients with amnestic mild cognitive impairment (aMCI). Further refinement of the stages based on neuropsychological and neuroimaging methods is important for earlier disease detection, as well as for the development and evaluation of disease-modifying interventions. In this cross-sectional study, 125 aMCI patients were classified into declined progressively three stages of mild, moderate and severe, utilizing the extreme groups approach (EGA) based on their memory function. Fifty-two patients, in addition to 24 cognitively normal subjects, were included in further structural MRI analyses. Characteristics of cognitive functions and brain structures across these newly defined stages were explored through general linear models. Almost all the non-memory cognitive functions showed progressive decline as memory function deteriorated. In addition, medial structures including the right hippocampus, right lingual and left fusiform gyrus, presented with greater gray matter (GM) atrophy during the later stages of aMCI (corrected < 0.05). Correlations were found between GM volume of the lingual gyrus and processing speed ( = 0.419, = 0.003) and between the fusiform gyrus and general cognitive function ( = 0.281, = 0.046). Moreover, both cognitive function and GM volume presented non-linear trajectories over stages of aMCI. Our study characterized the cognitive profiles along with the degree of episodic memory impairment, and these three stages of aMCI showed non-linear progressive decline in cognitive functions and GM volumes.
众所周知，在遗忘型轻度认知障碍（aMCI）患者中，存在与阿尔茨海默病（AD）相关的广泛不同病理阶段。基于神经心理学和神经影像学方法对这些阶段进行进一步细化，对于疾病的早期检测以及疾病修饰干预措施的开发和评估都很重要。在这项横断面研究中，125名aMCI患者根据其记忆功能，采用极端组方法（EGA）被分为轻度、中度和重度逐渐衰退的三个阶段。除了24名认知正常的受试者外，52名患者被纳入进一步的结构磁共振成像分析。通过一般线性模型探索了这些新定义阶段的认知功能和脑结构特征。随着记忆功能的恶化，几乎所有非记忆认知功能都呈现出逐渐下降的趋势。此外，包括右侧海马体、右侧舌回和左侧梭状回在内的内侧结构，在aMCI后期出现了更大程度的灰质（GM）萎缩（校正后<0.05）。发现舌回的GM体积与处理速度之间存在相关性（=0.419，=0.003），梭状回与一般认知功能之间存在相关性（=0.281，=0.046）。此外，认知功能和GM体积在aMCI各阶段均呈现非线性轨迹。我们的研究描述了认知概况以及情景记忆损害程度，并且aMCI的这三个阶段在认知功能和GM体积方面呈现出非线性的逐渐下降。
