Mild cognitive impairment and vascular cognitive impairment in stroke patients

In 150 older stroke patients (>75) without dementia, the proportion of people meeting different criteria for early cognitive impairment varied from 17% to 23% depending upon the individual criteria used. Given this large disparity, prospective studies to clarify the utility of different criteria as a predictor of subsequent dementia are a priority.     

皮质下缺血性脑血管病认知功能障碍研究

目的应用系列神经心理学测试分析皮质下缺血性脑血管病(SIVD)患者的认知损害特征。方法入选SIVD患者53例,年龄及性别相当的健康老年人25例为正常对照组。SIVD患者按照认知损害的诊断标准分为血管性痴呆(VaD)组27例和血管性认知障碍非痴呆(VCIND)组26例。进行MMSE及血管性痴呆包括记忆力、注意力、语言、视空间结构及执行功能5个认知域在内的神经心理学测试,确定VCIND患者受损的认知域。结果①与正常对照组比较,VaD组患者各项量表测试均严重受损,具有统计学差异(P﹤0.05);②VCIND组患者MMSE、数字倒背评分下降,连线测验时间延长,差异有统计学意义(P﹤0.05);③VaD组与VCIND组相比,上述各项均受损严重,其中单词回忆、连线测验、画钟测验、数字广度测验评分差异有统计学意义(P﹤0.05)。结论①SIVD患者同时存在多个认知域损害,以执行功能、注意力损害较为突出,记忆、语言受累相对较轻;②VCIND患者表现为执行功能、注意力受损,程度均低于VaD组,晚期VaD患者全面认知功能明显下降。     

血管性认知障碍的研究进展

血管性认知障碍(Vascular Cognitive Impairment, VCI)的概念最早由Hachinski和Bowler[1]于1993年提出,指单纯由于血管因素引起的轻度认知功能减退.随着研究的深入,VCI的概念得到不断的修改和完善,现将其定义为一类特征为影响至少一个认知区域的临床卒中或者亚临床脑损伤的临床综合征,其伴随的认知功能障碍,涵盖了从血管来源的轻度认知功能障碍(Vascular Mild Cognitive Impairment, VaMCI)到重度血管性痴呆(Vascular Dementia,VaD)的认知缺陷的所有表现形式[2].     

从血管性痴呆到血管性认知功能损害

本文通过回顾血管性痴呆的提出及争议，引出血管性认知功能损害提出的背景及其必要性，阐述了其诊断标准目前存在的问题及新近的研究进展，旨在通过比较血管性痴呆到血管性认知功能损害定义的演变说明血管性认知功能损害这一定义的重要性，指出寻找血管性认知功能损害特异性的神经心理学表现、影像学特点、生物学标记以及病理学特点将是今后。     

Clinical significance of subcortical vascular disease in patients with mild cognitive impairment

Patients with mild cognitive impairment (MCI) typically present with memory complaints. Some of these patients have subcortical vascular disease on computed tomography (CT) scan, namely white matter changes and lacunar infarcts, however it is not known whether these findings are associated with more pronounced cognitive deficits. In the present study we compare demographic, clinical and neuropsychological characteristics of MCI patients according to the presence or the absence of subcortical vascular disease. Forty consecutive patients with memory complaints, at least one neuropsychological memory test below 1 SD the normal for age and education, and maintained activities of daily living, were included. Patients with dementia, history of stroke or transient ischemic attack, or other brain disorders, were excluded. Twenty-five (62.5%) patients with MCI had no ischemic lesions on CT scan, and 15 (37.5%) were found to have subcortical vascular changes. MCI patients with subcortical vascular changes were older (77.1 +/- 6.8 vs. 70.8 +/- 7.5 years old), and more often males. The number of vascular risk factors, the frequency of neurological signs, the Hachinski score and the neuropsychological tests scores were not significantly different. The presence of subcortical vascular disease on CT scan is frequent in older patients with MCI, but does not appear to be associated with the severity of cognitive deficits.     

血管性痴呆与血管性认知损害的再认识

血管性痴呆(VaD)系指由脑血管病(包括出血性和缺血性脑血管病)导致的、影响日常生活活动能力(ADL)的认知功能障碍.血管性痴呆的两项核心要素是:临床痴呆综合征及作为痴呆病因的脑血管病的客观证据.     

Neuropathology of vascular cognitive impairment and vascular dementia

Understanding of vascular substrates of cognitive decline in the elderly is evolving to include a major emphasis on the impact of small vessel disease (SVD). While existing concepts of multi-infarct dementia and strategic infarct dementia remain valid, they present difficulty in generalizing clinicopathological correlations from patient to patient. The range and significance of lesions that should be included as manifestations of SVD are unresolved, as is their impact on, and association with, neurodegenerative changes. This mini-review summarizes the authors' views on SVD substrates leading to cognitive decline and proposes priorities for pathological investigations of human cerebrovascular mechanisms leading to cognitive decline.     

Behavioral symptoms in vascular cognitive impairment and vascular dementia

Noncognitive or behavioral and psychological symptoms (BPSD) are common in vascular dementia. Many occur with the same frequency as in Alzheimer's disease, though depression, emotional lability, and apathy may be more common and psychosis less so. There is a particularly strong relationship between cerebrovascular disease and depression.     

Dementia and cognitive impairment in Parkinson''s disease.

The frequency of dementia, the clinical characteristics and the pattern of cognitive impairment were studied in 147 unselected Parkinsonian patients. Twenty-one patients (14.28%) were judged to be demented. They had a more severe and widespread cognitive deficit although they were affected particularly in those tests that already discriminated Parkinsonian patients from controls. A direct comparison of Parkinsonian dementia with other types of dementia is needed to validate the concept of subcortical dementia.     

Conceptual background to vascular cognitive impairment

The current criteria for vascular dementia use a paradigm that first diagnoses dementia on the basis of Alzheimer-type criteria and then superimposes upon this vascular events and risk factors to convert a diagnosis of Alzheimer disease to one of vascular dementia. There are two fundamental flaws with this approach. First, the neuropsychological features of Alzheimer disease are not the same as those for vascular dementia and so use of the current criteria will fail to diagnose many cases, particularly those in whom memory loss is not prominent. Second, progression of vascular dementia should be modifiable by adjustment of risk factors and, possibly, by the use of neuroprotective agents. Given this, it is absurd to wait until patients are frankly demented. It is far more appropriate to detect patients at risk of developing cognitive loss as soon as possible. This could be in the earliest symptomatic stage (vascular cognitive impairment) or even prior to this (brain-at-risk) stage. New criteria, based on evidence rather than on supposition, that focus on early disease are urgently needed.     

Epidemiology: identifying vascular cognitive impairment

There has been a move in recent years to recognize that the most effective treatment for vascular dementia, and for the mixed component of mixed vascular dementia and Alzheimer's disease, lies not in treatment but in prevention. This requires that cases be identified before the onset of vascular damage (a stage termed "brain-at-risk") or, failing this, as soon as possible but certainly before dementia has developed. These early stages are termed vascular cognitive impairment (VCI). No criteria exist for this early stage of cognitive loss due to cerebrovascular disease and relatively little data exist to indicate how such cases might be identified. The data that do exist suggest that many of the traditional "vascular" features of sudden onset and stepwise progression, etc., are not common in VCI and new criteria will be needed to identify cases. This paper summarizes the data that describe the clinical, neuropsychological, and radiological features that are to be expected in VCI.     

阿尔茨海默病及血管性认知损害的神经影像学研究进展

认知功能障碍是年龄相关性神经变性疾病,常见原因为阿尔茨海默病(AD)和血管性认知损害(VCI)两大类.阿尔茨海默病是以进行性认知功能障碍和记忆损害为特征的神经系统退行性疾病,细胞外神经炎性斑[NPs,又称老年斑(SPs)]、神经原纤维缠结(NFTs)和神经毡细丝的形成是其主要病理改变.