老年轻度认知功能损害的4种脑诱发电位实验研究

目的 探讨老年轻度认知功能损害（MCI）的脑诱发电位（BEPs)变化。方法 应用美国Nicolet Spirit脑电生理仪记录23例MCI老年人（MCI组）的脑干听觉效应（ABR）,关联性负变（CNV）,P300和视觉诱发电位,并与29名认知功能正常的老年人（NC组）进行比较。结果 （1）与NC组相比,MCI组的听觉脑干反应波V绝对波幅和P300的P3靶波幅显著降低（P＜0．01）。（2）多元逐步判别分析;ABR波V绝对波幅和P300的P3靶波幅具有极显著性判别意义（P＜0．01）,两组判别总正确率为75％。结论 多项BEPs检测有助于MCI的诊断。     

老年认知功能损害的脑诱发电位研究

目的：探讨阿尔茨海默病（AD）和老年轻度认知功能损害（MCI）的脑诱发电位（BEPs）变化。方法：用美国Nicolet Spirit脑电生理仪记录24例AD病人（AD组）和23例MCI患者（MCI组）的脑干听觉反应（ABR）、关联性负变（CNV）、P300和视觉诱发电位（VEP），并与29名认知功能正常的老年人（NC组）进行比较。结果：（1）3组间大部分的BEPs检测指标的差异有显著性，AD组与NC组之间差异有显著性的指标比AD组与MCI组之间要多；（2）MCI与NC组相比，MCI组的ABR波V绝对波幅和P300的P3靶波幅显著降低；（3）多元逐步判别分析，ABR波Ⅲ绝对潜伏期及绝对波幅、波V对波幅及绝对潜伏期、CNV的反应时间和P300的P3靶波幅具有显著性判别意义，3组的判别总正确率为84.2%。结论：多项BEPs检测有助于AD的诊断，ABR的波V绝对波幅和P300的P3靶波幅显著降低具有早期诊断价值。     

晚发型抑郁障碍与轻度认知功能损害患者的认知功能差异研究

目的 探讨晚发型抑郁障碍患者与轻度认知功能损害患者的认知功能损害的差异.方法 研究对象为2012年7月～2013年8月上海市精神卫生中心老年科住院与门诊就诊符合DSM—Ⅳ诊断标准且起病年龄≥60岁的抑郁障碍患者,共26例为晚发型抑郁障碍组（LOD组）,另选择26例轻度认知功能损害的患者（MCI组）与26例正常老年人（NC组）.认知功能评估采用简明精神状态量表（MMSE）、蒙特利尔量表（MoCA）.结果 MMSE总分、MMSE分测验中计算力与注意力及MoCA总分、MoCA分测验中连线、注意、持续注意、计算、复述、延迟回忆在LOD组与MCI组差比较异无统计学意义（P＞0.05）,两组与NC组比较差异有统计学意义（P＜0.05）.三组在MMSE分测验的时间定向、延迟回忆、三步指令、书写书面指令及MoCA分测验的复制图、画钟、命名比较,MCI组均值最低,与NC组比较差异有统计学意义（P＜0.05）,与LOD组比较差异无统计学意义（P＞0.05）.结论 LOD组认知功能在注意力、延迟回忆、连线测验方面与MCI组损害程度相当.MCI组认知功能受损范围较LOD组广泛.     

社区正常老年人和轻度认知功能损害老年人的随访研究

目的了解社区正常和轻度认知功能损害（MCI）老年人的认知功能变化特点和转归。方法分别于2000年5月和2004年6月（时隔4年）对杭州市186名≥60岁老年人采用分层、分段、随机抽取方法进行调查。两次调查的程序和使用工具相同，采用美国精神障碍诊断与统计手册第4版进行诊断，用世界卫生组织老年认知功能评价成套神经心理测验（WHO-BCAI）进行测查。结果（1）在2000年调查时诊断为正常的127例中，4年后有97例（76．4％）正常（NC组），16例（12．6％）为MCI（MCI组），14例（11．0％）为痴呆（痴呆组）；而2000年诊断为MCI的18例，4年后全部发展为痴呆。（2）与NC组比较，除性别外，MCI组的年龄大、教育水平低、从事体力劳动和不良婚姻事件多（P〈0．05和P〈0．01），痴呆组的年龄大和男性比例高（均P〈0．05和P〈0．01）。（3）WHO-BCAI测验，2004年与2000年比较，三组各项测验的成绩均有所下降（P〈0．01或P〈0．05），其中以痴呆组为著；而MCI组在听觉词汇学习第4次测验、语言能力测验（小标记测验）、视觉辨认测验（语义联系、视觉推理）、连线测验、注销测验（注销测验2和3）、运动测验和空间结构等项下降明显。结论老年期MCI患者的认知功能损害和功能下降呈进行性加重，主要表现为学习、近记忆能力、记忆再现、语义记忆、抽象思维能力、空间感知及执行功能受损。     

轻度认知功能障碍老年人和阿尔茨海默病患者听觉事件相关电位P300比较

目的探讨轻度认知功能障碍老年人(MCI)和阿尔茨海默病(AD)在事件相关电位(ERP)P300检测中的不同表现.方法收集符合ICD-10诊断标准的36例MCI患者和30例AD,并以45例健康老人作对照组(NC).使用美国仪器以及"听觉靶-非靶刺激序列"为诱发事件,完成P300检测.结果 (1)3组和NC组在靶潜伏期Fz脑区N2以及在靶波幅Fz脑区P2P3和非靶波幅Fz脑区P2上均有显著差异(P＜0.01).(2)AD主成分N2表现为延迟,与NC组和MCI组有极显著性差异(P＜0.01).(3)MCI组和AD组靶波幅P3和非靶波幅P2均见降低,与NC组比较也有显著性差异(P＜0.05～＜0.01).结论提示作为反映MCI和AD认知功能障碍的客观生理指标,P300有可能作为MCI和AD辅助诊断的一个脑电生理学标志.P300检查可作为老年精神科的必查项目.     

成功老龄化机制的系列研究:随访部分

目的探索成功老龄（SA）化的可能机制。，方法（1）样本来源于社区≥65岁老年人。共完成随访156例，其中成功老龄（SA）组73例，常态老龄（uA）组57例，轻度认知功能损害（MCI）组26例。（2）研究工具采用中国老年成套神经心理测验和上海市社区老年人群健康问卷SA2004等。结果（1）SA组老年人在即刻记忆、延迟记忆、长时记忆提取相关测验成绩随访前后差异无统计学意义（P〉0．05），执行功能、序列学习和逻辑推理相关测验成绩随访前后差异有统计学意义（P〈0．05）；UA组老年人在工作记忆、执行功能方面的下降有统计学意义（P〈0．05）；MCI组老年人成绩的下降项目仅4项。（2）按年龄分组后，神经心理项目测验成绩随访前后比较，差异有统计学意义（P〈0．05）的分量表有10项，其中有9项在71—75岁组下降数值相对最大。（3）躯体活动能力、心理状况及认知功能等基线指标与随访结局指标（健康状况调查问卷各分量表评分）的差异有统计学意义（P〈0．05）。结论（1）SA老年人的高认知水平与大脑的整合功能及有效代偿相关，认知老化过程中执行功能可能属于易感领域，而71—75岁则可能是老年人认知老化的敏感时期。（2）UA、MCI老年人的认知功能仍具一定的可塑性，SA化干预具有现实意义。     

轻度认知功能障碍患者海马、内嗅皮层体积与嗅觉功能改变的临床研究

目的探讨轻度认知功能障碍(Mild Cognitive I mpairment,MCI)患者的海马、内嗅皮层体积与嗅觉功能变化及其相关性。方法从体检者中入选MCI组21例,认知功能正常(NC)组18人,进行一般情况评定、实验室检查和神经心理量表评测。MRI测量海马体积和内嗅皮层体积,"五味嗅觉测试液"进行嗅觉功能的评测并进行与认知功能的相关性分析。结果MCI组与NC组相比内嗅皮层体积[MCI组(2.661±0.173)cm3,NC组(3.033±0.122)cm3,P0.01]与海马体积[MCI组(6.186±0.740)cm3,NC组(6.802±0.796)cm3,P0.05]均有明显萎缩。MCI组的嗅觉识别阈值(2.429±0.263)分明显高于NC组(2.089±0.308)分(P0.01)。海马体积与内嗅皮层体积、临床记忆量表总分及嗅觉识别阈值显著相关(P0.01);内嗅皮层体积与临床记忆量表总分呈正相关,与嗅觉识别阈值呈负相关(P0.01);临床记忆量表总分与嗅觉识别阈值呈显著负相关(P0.01)。结论MCI患者存在海马、内嗅皮层萎缩及嗅觉识别或能的下降,MRI测量海马、内嗅皮层体积及嗅觉功能评定对诊断MCI及早期进行阿尔茨海默病防治有重要参考价值。     

基于体素的MRI形态学测量对遗忘型轻度认知障碍和轻度阿尔茨海默病脑灰质萎缩的研究

目的：利用磁共振3DT1WI成像研究遗忘型轻度认知障碍（aMCI）、轻度阿尔茨海默病（AD）患者相对于正常老年人灰质体积改变的特点。方法：采用3．0T磁共振,对33例aMCI患者（aMCI组）、32例轻度AD患者（轻度AD组）及31名正常老年人（对照组）进行3DT1WI扫描,利用基于SPM5的DARTEL工具箱对扫描获得的结构图像进行预处理,再对aMCI组、轻度AD组和对照组的全脑灰质体积进行基于体素的统计学比较。结果：与对照组比较,aMCI组左侧海马、海马旁回、舌回、颞上回,双侧岛叶和颞中回等结构的灰质体积萎缩,其差异有显著统计学意义（P〈0．01,FDR corrected,K〉50体素）。轻度AD组的双侧海马、海马旁回及杏仁核、双侧丘脑、双侧颞顶叶皮质等结构灰质体积萎缩,额叶和枕叶皮质也出现灰质萎缩,其差异也有统计学意义（P〈0．05,FDR corrected,K≥50体素）。结论：基于体素的MRI形态学测量能够客观揭示AD早期阶段的脑灰质萎缩改变,对左侧海马萎缩的识别有助于AD的早期诊断。     

轻度认知功能障碍老年人的睡眠实验研究

目的探讨轻度认知功能障碍（MCI）老年人多导睡眠图（PSG）变化特点。方法应用多导睡眠生理仪,采用眼电图和下颌肌电图及脑电图技术,对19例MCI老年人（MCI组）的PSG进行全夜监测,并与20名正常老年人（NC组）对照。结果与NC组比较,MCI组睡眠总时间减少[NC组（381±37）min,MCI组（313±67）min,P〈0.01],觉醒时间增加[NC组（30±10）min,MCI组（53±17）min,P〈0.01],睡眠维持率下降[NC组（94±10）%,MCI组（85±13）%,P〈0.05],第1阶段睡眠增加[NC组（14±2）%,MCI组（28±10）%,P〈0.01],第2阶段睡眠降低[NC组（60±4）%,MCI组（51±18）%,P〈0.05]和第3阶段睡眠降低[NC组（9±5）%,MCI组（4±3）%,P〈0.01],REM强度增强[NC组（21±4）%,MCI组（40±22）%,P〈0.01]。结论PSG中的浅睡眠增多,慢波睡眠S3减少可能是MCI病人所具有的电生理学指标之一。     

轻度认知障碍和轻度Alzeimer病的海马体积MRI测量

目的研究轻度认知功能障碍（mildcognitiveimpairment,MCI）和轻度阿尔兹海默病（A1zheimerdisease,AD）患者的海马体积萎缩情况,评价利用影像学测定海马体积对MCI、AD的诊断价值。方法应用3．0T磁共振分别对20例MCI患者,20例轻度AD患者,20例认知功能正常的对照者的海马体积进行测量,所得数值用头颅体积进行标准化处理。采用计算机SPSS13．0统计学软件进行资料的统计学处理,比较三组之间体积的差异。结果对照组与MCI组,对照组与AD组的两侧海马体积均存在显著的统计学差异,轻度AD与MCI组两侧的海马体积无显著的统计学差异。结论认知功能障碍与海马体积具有一定的相关性,海马萎缩对早期认知障碍有一定的诊断意义。     

Plasma ceramides are altered in mild cognitive impairment and predict cognitive decline and hippocampal volume loss

BackgroundA blood-based biomarker of Alzheimer's disease (AD) would be superior to cerebrospinal fluid (CSF) and neuroimaging measures in terms of cost, invasiveness, and feasibility for repeated measures. We previously reported that blood ceramides varied in relation to timing of memory impairment in a population-based study. The present objective was to examine whether plasma ceramides varied by AD severity in a well-characterized clinic sample and were associated with cognitive decline and hippocampal volume loss over 1 year.MethodsParticipants included 25 normal controls (NC), 17 amnestic Mild Cognitive Impairment (MCI), and 21 early probable AD. A thorough neuropsychological battery and neuroimaging with hippocampal volume determination were conducted at baseline and 1 year later. Plasma ceramides were assayed at baseline using high performance liquid chromatography coupled electrospray ionization tandem mass spectrometry.ResultsAlthough all saturated ceramides were lower in MCI compared with AD at baseline, ceramides C22:0 and C24:0 were significantly lower in the MCI group compared with both NC and AD groups (P < .01). Ceramide levels did not differ (P > .05) in AD versus NC. There were no cross-sectional associations between ceramides C22:0 and C24:0 and either cognitive performance or hippocampal volume among any group. However, among the MCI group, higher baseline ceramide C22:0 and C24:0 levels were predictive of cognitive decline and hippocampal volume loss 1 year later.ConclusionResults suggest that very long-chain plasma ceramides C22:0 and C24:0 are altered in MCI and predict memory loss and right hippocampal volume loss among subjects with MCI. These plasma ceramides may be early indicators of AD progression.     

Ventricular enlargement and mild cognitive impairment in early Parkinson's disease

Mild cognitive impairment (MCI) may predict future development of dementia in Parkinson's disease (PD). We aimed to examine the extent of subcortical brain atrophy in patients with early PD with and without MCI compared to normal controls (NC). Participating in a population‐based study were 43 early, drug‐naïve PD patients and 41 NC. Eleven patients were classified with MCI (MCI PD) and 32 patients without (non‐MCI PD). Volumetric segmentation of 3D‐T1 weighted brain MRI was performed using FreeSurfer. Groups were compared applying MANCOVA corrected for total intracranial volume, age, and sex. Results showed that left inferior lateral ventricle and third ventricle volumes were significantly larger in MCI PD than in non‐MCI PD and NC. Fourth ventricular size in MCI PD was significantly different from NC and highly correlated with memory performance in MCI PD patients. This suggests that cognitive dysfunction in early PD may be associated with ventricular enlargement. © 2010 Movement Disorder Society     

Functional and anatomical memory indices in patients with or at risk for Alzheimer's disease.

We investigated the sensitivity of the P300 event-related brain potential (ERP) recorded during a memory-demanding task to memory function in subjects with dementia of the Alzheimer's type (DAT), those with mild cognitive impairment (MCI), and normal elderly controls. We also explored the ability of neuropsychological (delayed verbal memory), neuroanatomical (MRI-based hippocampal volume), and electrophysiological (memory search P300 amplitude) memory measures to distinguish between the three subject groups using discriminant function analyses. Fourteen patients with DAT, 16 with MCI, and 15 age- and education-matched controls were tested. P300 amplitude was reduced in DAT subjects at all levels of memory load; however, it did not differ between MCI and control subjects. Delayed verbal memory performance best discriminated DAT from MCI and control subjects, while delayed verbal memory and hippocampal volume best discriminated MCI subjects from controls. These results support the utility of neuropsychological and neuroanatomical measures in diagnosing dementia and do not support the notion that P300 amplitude is sensitive to mild memory dysfunction when measured using the current task.     

老年人轻度认知功能损害的神经心理测验研究

目的;用神经心理测验研究老年人轻度认知功能损害的特点。方法;为横断面比较研究。研究对象分为两组,即有轻度认知功能损害的老年人（ＭＣＩ组）和认知功能正常的老年人（对照组,ＮＣ组）。以世界卫生组织老年认知功能介成套神经心理测验（ＷＨＯ－ＢＣＡＩ）为主要研究工具。     

Clinical correlates of functional performance in community-dwelling Chinese older persons with mild cognitive impairment

ABSTRACTBackground: Increasing evidence suggests that functional impairment can be detected in older persons with mild cognitive impairment (MCI). This study explores the functional profiles and the clinical correlates of a population-based sample of Chinese older persons with MCI in Hong Kong.Methods: A random sample of 765 Chinese elderly subjects without dementia was recruited, of which 389 were elderly normal controls (Clinical Dementia Rating = 0), and 376 had questionable dementia (CDR = 0.5). The latter were categorized into an MCI group (n = 291) and a very mild dementia (VMD) group (n = 85). Their functional performances were measured and compared with the normal controls (NC). Multiple regression analyses investigated the associations between functional scores (Disability Assessment in Dementia) and clinical correlates (cognitive test scores, neuropsychiatric symptoms and motor signs) in the NC subjects and cognitively impaired subjects.Results: Subjects with MCI had intermediate functional performance between the NC and those with VMD. Regression analyses revealed that lower scores of cognitive tests (delayed recall and categorical verbal fluency tests), apathy, aberrant motor symptoms and parkinsonism features were associated with lower functional scores in clinically non-demented subjects. Functional scores had no correlation with age, education and medical illness burden.Conclusion: Neuropsychiatric symptoms and parkinsonism features were associated with functional impairment in the clinically non-demented elderly in the community. Assessment of these should be incorporated in the evaluation of older persons for early cognitive impairment.     

Volumetric MRI measurements can differentiate Alzheimer's disease,mild cognitive impairment,and normal aging

BACKGROUND: Volumetric magnetic resonance imaging (MRI) has been extensively studied in the last decade as a method to help with the clinical diagnosis of Alzheimer's disease (AD). In recent years, researchers have also started investigating if that technique would be useful to identify individuals with mild cognitive impairment (MCI), differentiating them from AD patients and from normal elderly controls. This research project was planned to assess the accuracy of volumetric MRI to differentiate those groups of individuals. METHOD: The investigation involved 39 patients with diagnosis of mild to moderate dementia in AD, according to the criteria of the NINCDS-ADRDA, DSM-III-R, and ICD-10; 21 subjects with complaints of cognitive decline without other psychiatric disorders (MCI); and 20 normal elderly controls. All the subjects were submitted to a standard protocol, including volumetric MRI evaluations. RESULTS: The results indicated that all regions of interest measured (amygdala, hippocampus, and parahippocampal gyrus) were significantly different (p < .005) in AD patients compared to MCI subjects and controls. The left volumetric measures (amygdala, hippocampus, and parahippocampal gyrus) were also significantly different between the MCI subjects and controls (p < .05). The discriminant function analysis correctly classified 88.14% of the AD patients and controls, 81.67% of AD patients and MCI subjects, and 80.49% of the MCI subjects and controls. CONCLUSIONS: The results suggest that measures of medial temporal lobe regions are useful to identify mild to moderate AD patients and MCI subjects, separating them from normal elderly individuals.     

Magnetic resonance imaging white matter hyperintensities and brain volume in the prediction of mild cognitive impairment and dementia

OBJECTIVE: To determine whether magnetic resonance imaging (MRI) white matter hyperintensities (WMH), whole-brain atrophy, and cardiovascular risk factors predict the development of cognitive decline and dementia. DESIGN: Subjects were recruited into this prospective cohort study and followed for incident cognitive decline for mean (SD) 6.0 (4.1) years. Magnetic resonance imaging dual-echo sequences, obtained at baseline, were used to determine the volume of WMH and the brain parenchymal fraction (BPF), the proportion of the intracranial cavity occupied by brain. White matter hyperintensity volume was analyzed as the percentage of intracranial volume (WMHr); "high WMH" was defined as a WMHr more than 1 SD above the mean. SETTING: General community. PATIENTS: Volunteer sample consisting of 67 subjects with normal cognition and 156 subjects with mild cognitive impairment (MCI). MAIN OUTCOME MEASURES: Time to diagnosis of MCI (among those with normal cognition at baseline) or time to diagnosis of dementia, either all-cause or probable Alzheimer disease (AD) (among those with MCI at baseline). Cox proportional hazards models were used for multivariable analysis. RESULTS: High WMH was a predictor of progression from normal to MCI (adjusted hazard ratio [HR], 3.30; 95% confidence interval [CI], 1.33-8.17; P= .01) but not conversion from MCI to all-cause dementia. Conversely, BPF did not predict progression from normal to MCI but did predict conversion to dementia (adjusted HR, 1.10 for each 1% decrease in BPF; 95% CI, 1.02-1.19; P= .02). When conversion to AD dementia was considered as the outcome, BPF was likewise a predictor (adjusted HR, 1.16 for each 1% decrease in BPF; 95% CI, 1.08-1.24; P< .001), but high WMH was not. Past tobacco smoking was associated with both progression from normal to MCI (adjusted HR, 2.71; 95% CI, 1.12-6.55; P= .03) and conversion to all-cause dementia (adjusted HR, 2.08; 95% CI, 1.13-3.82; P= .02), but not AD dementia. CONCLUSIONS: These findings suggest that WMH are associated with the risk of progressing from normal to MCI. In persons whose cognitive abilities are already impaired, BPF predicts the conversion to dementia.     

Adiponectin in plasma and cerebrospinal fluid in MCI and Alzheimer’s disease

Background and purpose: Life style‐related disorders such as hypertension, diabetes, dyslipidemia, and obesity are reported to be a great risk of dementia. Adipocytokines released from adipose tissue are thought to modulate some brain functions including memory and cognition. We here analysed adiponectin, one of the most important adipocytokines, in plasma and cerebrospinal fluid (CSF) from cognitive normal controls (NC), mild cognitive impairment (MCI) subjects, and patients with Alzheimer’s disease (AD) and discussed if/how adiponectin could relate to the pathogenesis of AD. Methods: Normal controls (n = 28), MCI (n = 18), and AD (n = 27) subjects were recruited at Tohoku University Hospital. The diagnosis of AD was based on NINCDS‐ADRDA criteria. All the blood and CSF samples were obtained from each fasted subject. Adiponectin was assayed using a sandwich ELISA system. Results: The levels of adiponectin between in plasma and in CSF showed a positive correlation. Plasma adiponectin was significantly higher in MCI and AD compared to NC, whereas CSF adiponectin was significantly higher in MCI compared to NC. Conclusion: It is possible that the level of adiponectin in plasma reflects its level in CSF. The tendency to have higher adiponectin in plasma and CSF from MCI and AD suggests that this molecule plays a critical role in the onset of AD.     

Magnetic resonance imaging of the entorhinal cortex and hippocampus in mild cognitive impairment and Alzheimer's disease

OBJECTIVES: To explore volume changes of the entorhinal cortex (ERC) and hippocampus in mild cognitive impairment (MCI) and Alzheimer's disease (AD) compared with normal cognition (NC); to determine the powers of the ERC and the hippocampus for discrimination between these groups. METHODS: This study included 40 subjects with NC, 36 patients with MCI, and 29 patients with AD. Volumes of the ERC and hippocampus were manually measured based on coronal T1 weighted MR images. Global cerebral changes were assessed using semiautomatic image segmentation. RESULTS: Both ERC and hippocampal volumes were reduced in MCI (ERC 13%, hippocampus 11%, p<0.05) and AD (ERC 39%, hippocampus 27%, p<0.01) compared with NC. Furthermore, AD showed greater volume losses in the ERC than in the hippocampus (p<0.01). In addition, AD and MCI also had cortical grey matter loss (p< 0.01) and ventricular enlargement (p<0.01) when compared with NC. There was a significant correlation between ERC and hippocampal volumes in MCI and AD (both p<0.001), but not in NC. Using ERC and hippocampus together improved discrimination between AD and CN but did not improve discrimination between MCI and NC. The ERC was better than the hippocampus for distinguishing MCI from AD. In addition, loss of cortical grey matter significantly contributed to the hippocampus for discriminating MCI and AD from NC. CONCLUSIONS: Volume reductions in the ERC and hippocampus may be early signs of AD pathology that can be measured using MRI.