脑小血管病的发病机制和临床特点

脑小血管病(cerebral small vessel disease,SVD)是脑血管病的一个重要亚型,也是导致老年血管性认知障碍或痴呆的主要原因之一。SVD是由多种原因导致的脑皮质下微小动静脉病变,主要引起皮质下腔隙性梗死、白质损害、微出血等病理学改变。有证据表明,血管内皮功能和血脑屏障损害可导致小血管结构和血管周围改变,可能是引起SVD的初始因素。遗传易感性亦是不可忽视的危险因素之一。     

皮质下缺血性血管性痴呆的诊断和治疗

皮质下缺血性血管性痴呆主要以小血管疾病为病因,包括腔隙状态、关键部位梗死性痴呆和Binswanger综合征,临床上表现为皮质下综合征和认知障碍.积极诊断和治疗皮质下缺血性血管性痴呆有助于降低老年人认知障碍的发病风险.     

脑小血管病与认知损害

脑小血管病(small vessel disease,SVD)是指累及颅内小动脉、微动脉、前毛细血管和小静脉的疾病,影像学分型主要包括脑白质病变、腔隙性梗死和脑微出血,被认为是认知功能损害或血管性痴呆的独立危险因素.SVD病变部位、数量和体积均会影响认知损害的程度和表现.     

单基因遗传性脑小血管病的研究进展

脑小血管病(CSVD)指脑内小动脉、小静脉、微动脉、毛细血管等小血管病变导致的一种以认知障碍、进行性痴呆、脑卒中、精神行为异常等为主要表现的脑功能损伤综合征。根据单基因遗传病导致血管病变的机制可将CSVD分为血管平滑肌细胞病、血管间质性疾病、血管内皮细胞病、血管代谢性疾病等。本文主要综述了单基因遗传性CSVD的遗传方式、病理特点、临床表现、影像学表现等,以期为临床有效诊治此类疾病提供参考。     

老年脑梗死与认知功能障碍

脑梗死可以引起局灶性运动（感觉）定位体征，也经常伴有认知障碍，并且随年龄增长而加重。血管性认知障碍（vascular cognitive impairment，VCI）是近年来提出的新的概念，它包括：VCI非痴呆，血管性痴呆（vascular dementia，VaD）及混合性血管病变与神经变性病所致的痴呆（例如阿尔茨海默病伴脑血管病变）。在老年期痴呆性疾病中，VaD是第二主要疾病，仅次于阿尔茨海默病，约占20％-30％。     

血管性痴呆与血管性认知障碍

由于传统痴呆定义的束缚,目前的血管性痴呆诊断标准不能发现非痴呆的认知障碍,也难以与混合性痴呆相区别,更不能促进血管性痴呆的防治。用血管性认知障碍的概念则可以涵盖所有与血管危险因素和脑血管病变有关的各种程度的认知障碍,促进早期识别和早期干预。     

血管性认知损害的筛查工具与早期诊断

血管性认知损害(vascular cognitive impairment,VCI)是由脑血管病危险因素(如高血压、心脏病、糖尿病和高血脂等)、明显(如脑梗死和脑出血等)或不明显的脑血管病(如白质疏松和慢性脑缺血等)引起的从轻度认知障碍到痴呆的综合征[1,2].目前较为统一的意见是VCI包括3个内容[3～6]:非痴呆型血管性认知损害 (vascular cognitive impairment,no dementia,VCIND)、血管性痴呆(vascular dementia,VD )、AD伴血管病变(即混合性痴呆,mixed AD/VD).与血管性痴呆相比,其内涵有了扩展,认知障碍不强调记忆力损害,只要有某些认知领域的功能下降,即使没有记忆力减退,仍然可定性为认知障碍;同时,"血管性"不特指脑出血或梗死,还包括各种可能影响脑功能的心脑血管病变.     

血管性痴呆与血管性认知障碍

由于传统痴呆定义的束缚，目前的血管性痴呆诊断标准不能发现非痴呆的认知障碍，也难以与混合性痴呆相区别，更不能促进血管性痴呆的防治。用血管性认知障碍的概念则可以涵盖所有与血管危险因素和脑血管病变有关的各种程度的认知障碍，促进早期识别和早期干预。     

血管性认知功能障碍的防治

有关血管病变与认知障碍的相关性研究由来已久。早在19世纪后期就曾有病理学家提出了"动脉硬化性痴呆"这一概念,后演变成现今表述的血管性痴呆(VaD)。与阿尔茨海默病(AD)相比,VaD具有相对的可预防性和可治疗性。但VaD这一概念将伴     

卒中后认知障碍

卒中后认知障碍包括卒中后非痴呆认知障碍和卒中后痴呆,是卒中后由血管因素、神经变性或混合因素导致的认知功能障碍.卒中后认知障碍的慨念虽未被普遍接受,但值得进一步探讨.文章介绍了卒中后认知障碍的流行病学、危险因素、发病机制、临床表现和防治措施.     

脑小血管病与认知功能障碍

脑小血管病是指颅内小动脉和做动脉病变引起脑的缺血或出血损害,是血管性认知功能障碍的重要亚型。其主要的影像学表现为腔隙性脑梗死、脑白质疏松和脑做出血。脑小血管病的临床分类主要包括腔隙综合征、Binswanger脑病、脑淀粉样血管病、伴有皮质下腑梗死和白质肭痫的常染色体显性遗传性脑动脉病、伴有皮质下脑梗死和白质脑病的常染色体隐性遗传性脑动脉病及其它较少见的小血管病。其临床表现则丰要为静灶腑血管病（静灶腔隙性脑梗化、脑微出血和部分白质疏松）、各类腔隙综合征和血管性认知功能障碍。     

Do Alzheimer's disease (AD) and subcortical ischemic vascular dementia (SIVD) progress differently?

Our study aimed to compare cognitive status and declines in AD with/without small vessel disease (SVD) and SIVD at baseline and 1-year follow-up. Patients with Alzheimer's disease without small vessel disease (AD(−)SVD) (n = 148), Alzheimer's disease with small vessel disease (AD(+)SVD) (n = 94) and SIVD (n = 60) were recruited from database of multiple centers in Korea. Basic demographics and detailed neuropsychological results were compared. AD, regardless of SVD, showed worse memory and better executive function than SIVD at baseline. Mini-Mental State Examination scores and visual memory function declined more in AD than those in SIVD whereas Barthel Activities of Daily Living (B-ADL) scores declined more in SIVD. AD showed different patterns of cognitive impairment compared with SIVD. After 1 year, AD showed more rapid cognitive decline in some domains. Further investigations with longer follow-up duration may be needed to confirm the cumulative effects of SVD in AD and different patterns of decline between AD and SIVD.     

Does cerebral small vessel disease predict future decline of cognitive function in elderly people with type 2 diabetes?

Aims

We conducted a 3-year longitudinal study concerning an association between cognitive function and cerebral small vessel disease (SVD) seen on magnetic resonance imaging (MRI) in elderly type 2 diabetic patients.

Methods

Four cognitive function tests - MMSE, word recall, Digit Symbol Substitution (DSS), and Stroop Color Word (Stroop) - were performed in 67 diabetic patients twice in 2006 and 2009. SVD was diagnosed as silent brain infarct (SBI) and white matter lesions (WMLs) according to MRI.

Results

Number of SBI was significantly correlated with a decline in DSS and Stroop tests, while WMLs grade was only associated with it in DSS tests after adjustment for age, gender, education years, the presence of hypertension and dyslipidemia, and smoking. Severity of SVD at baseline was stronger associated with cognitive function after the 3-year follow-up than at baseline. WMLs progression was associated with more rapid decline of DSS tests compared to a group without progression.

Conclusions

SVD seen on MRI is a good marker for predicting future cognitive decline, and monitoring of treatment through the use of such markers is expected to maintain a good quality of life for elderly diabetic patients.     

Increased risk of cognitive impairment and more severe brain lesions in hypertensive compared to non‐hypertensive patients with cerebral small vessel disease

Although cerebral small vessel disease (SVD) is traditionally associated with aging and hypertension (HT), there are patients exhibiting sporadic SVD, free of HT. We aimed to investigate the differences in clinical and neuroradiological presentation in SVD patients in reference to the presence of HT as a risk factor (RF). Vascular RF, cognitive and functional status were evaluated in a cohort of 424 patients. Patients were classified in two groups based on the presence of HT. Severity of vascular lesions was assessed using 1.5 T magnetic resonance imaging with Age‐Related White Matter Changes scale total score (tARWMC) and Fazekas scale periventricular (PV) and deep subcortical (DS) scores. No difference between groups in age and sex distribution was noted. In univariate analysis, HT was associated with vascular cognitive impairment (vCI) (OR 2.30, 1.53‐3.45, P < 0.0001), functional status (OR 1.47, 1.11‐1.95, P = 0.007), depression (OR 2.13, 1.23‐3.70, P = 0.007), tARWMC (OR 1.10, 1.05‐1.16 95% CI, P < 0.0001), Fazekas PV score (OR 1.34, 1.08‐1.67 95% CI, P = 0.008), Fazekas DS score (OR 1.95, 1.44‐2.63 95% CI, P < 0.0001) and total number of lacunes (OR 1.10, 1.02‐1.18 95% CI, P = 0.009). Multivariate logistic regression analysis indicated that HT was an independent RF for vCI (OR 1.74, 1.09‐2.76 95% CI, P = 0.020) and higher Fazekas DS score (OR 1.57, 1.11‐2.22 95% CI, P = 0.011). The Kaplan‐Meier curve of estimates of survival of SVD patients without vCI revealed a higher proportion of patients with HT progressing to vCI over time when compared to HT‐free cases. In patients with sporadic SVD, HT is a contributing factor to worse clinical outcomes and neuroradiological presentation.     

轻度认知损伤患者异质性特点的研究

目的研究有轻度认知损伤的人群中可能存在的不同亚型,以便为轻度认知损伤患者的临床转归及痴呆的早期干预提供依据。方法选取简易智能状态检查、临床记忆量表、词语流畅性、数字广度、画钟表和相似性测验,从10个不同认知领域利用心理测评结果对58例轻度认知损伤患者进行聚类分析。所有轻度认知损伤患者可聚为3类,分别为36例、14例和8例。结果在3个类别之间有5项认知功能(临床记忆量表、画钟表测验、词语流畅性测验、数字广度测验、相似性测验)差异有显著性意义。结论在轻度认知损伤患者中可能主要存在三种亚型,一是以单纯记忆功能减退为主;二是多个认知领域轻度损伤;三是以非记忆功能减退为主;不同亚型的认知损伤范围和临床转归不同。     

军队体检人群应用两种量表筛查认知功能障碍的临床研究

目的探讨联合应用AD8和简易智力状态评估量表(Mini-Cog)在军队体检人群筛查认知功能障碍的特异性和敏感性。方法纳入我院常规健康体检军队人群1723例,对自愿接受认知功能测评者行AD8量表和Mini-Cog测评,最终同时接受AD8量表和Mini-Cog检测的体检者160例。采用ROC曲线分析量表评估的敏感性、特异性,计算ROC曲线下面积(AUC)。结果AD8量表和Mini-Cog测评提示认知功能障碍者分别为84例(52.5%)和71例(44.4%),两者联合检测提示双异常者为43例(26.9%)。160例受检者中临床诊断为认知功能障碍者66例(41.3%),其中AD8量表检出率为69.7%,Mini-Cog检出率为83.3%,两者联合检出率为56.1%。ROC曲线分析显示,两者联合检测特异性为93.6%,敏感性为56.1%。AD8(≥2分)量表、Mini-Cog及两者联合检测评估认知功能障碍的AUC比较,差异有统计学意义(P<0.01)。与认知正常者比较,双异常者年龄明显增高(P<0.01),在调整年龄的影响因素后,协方差分析显示,双异常者连线A完成时间明显延长,简易智能状态检查量表、延迟回忆、执行功能、工作记忆、词语流畅性评分明显降低(P<0.01)。结论AD8和Mini-Cog操作简单,测评所需时间短,两者联合检测可明显提高痴呆患者检出的特异性,适用于在初级医疗卫生保健机构筛查认知功能障碍患者。     

脑小血管病引起的认知障碍磁共振波谱和弥散张量成像

脑小血管病(cerebral small vessel disease,SVD)的临床症状主要表现为认知障碍,病理学改变则表现为白质疏松和(或)腔隙性梗死.然而,目前尚不清楚SVD引起的认知障碍是否与白质损害程度相关.磁共振波谱分析能无创件榆测活体脑组织的代谢产物浓度,直接反映脑代谢;弥散张量成像是特异性观察脑白质的无创性新技术,通过平均弥散、各向异性等不同参数来定量评价脑白质的细微结构异常.磁共振波谱分析与弥散张量成像联合应用能更敏感地显示白质损害程度,为SVD引起的认知障碍提供研究工具.     

Predicting cognitive impairment in high-functioning community-dwelling older persons: MacArthur Studies of Successful Aging

OBJECTIVES: To examine whether simple cognitive tests, when applied to cognitively intact older persons, are useful predictors of cognitive impairment 7 years later. DESIGN: Cohort study. SETTING: Durham, North Carolina; East Boston, Massachusetts; and New Haven, Connecticut, areas that are part of the National Institute on Aging Established Populations for Epidemiological Studies of the Elderly. PARTICIPANTS: Participants, aged 70 to 79, from three community-based studies, who were in the top third of this age group, based on physical and cognitive functional status. MEASUREMENTS: New onset of cognitive impairment as defined by a score of less than 7 on the Short Portable Mental Status Questionnaire (SPMSQ) in 1995. RESULTS: At 7 years, 21.8% (149 of 684 subjects) scored lower than 7 on the SPMSQ. Using multivariate logistic regression, three baseline (1988) cognitive tests predicted impairment in 1995. These included two simple tests of delayed recall-the ability to remember up to six items from a short story and up to 18 words from recall of Boston Naming Test items. For each story item missed, the adjusted odds ratio (AOR) for cognitive impairment was 1.44 (95% confidence interval (CI) = 1.16-1.78, P <.001). For each missed item from the word list, the AOR was 1.20 (95% CI = 1.09-1.31, P <.001). The Delayed Recognition Span, which assesses nonverbal memory, also predicted cognitive impairment, albeit less strongly (odds ratio = 1.06 per each missed answer, 95% CI = 1.003-1.13, P =.04). CONCLUSIONS: This study identifies measures of delayed recall and recognition as significant early predictors of subsequent cognitive decline in high-functioning older persons. Future efforts to identify those at greatest risk of cognitive impairment may benefit by including these measures.     

慢性阻塞性肺疾病伴认知功能障碍患者血清lipocalin-2表达及意义

目的分析血清脂质运载蛋白-2(lipocalin-2)在慢性阻塞性肺疾病(chronic obstructive pulmonary disease, COPD)稳定期伴认知障碍患者血清中的表达变化及其意义。 方法依据蒙特利尔认知评估量表(Montreal cognitive assessment, MoCA)评分,MoCA分值<26分者为认知受损,将43例COPD稳定期的患者分为认知障碍组23例及认知正常组20例,并选取20例健康体检者做对照组;采用酶联免疫吸附实验(ELISA)分别检测患者外周静脉血清脂质运载蛋白-2(lipocalin-2)水平;分析血清脂质运载蛋白-2与认知功能的相关性,根据血清lipocalin-2水平预测认知障碍的受试者工作特征(ROC)曲线。 结果与健康对照组相比(60.37±10.77)μg/ml,COPD稳定期伴认知障碍患者血清lipocalin-2水平(82.76±12.90)μg/ml显著增加(P<0.05);与COPD稳定期认知正常组(69.70±11.51)μg/ml相比,认知功能障碍组血清lipocalin-2水平显著升高,差别有统计学意义(P<0.05)。Pearson相关分析结果显示血清lipocalin-2水平与MoCA评分呈负相关(r＝-0.749,P<0.001);血清lipocalin-2水平预测COPD稳定期患者认知功能障碍的ROC曲线下面积分别为0.804(95%CI 0.664~0.945,P<0.001)。 结论血清lipocalin-2表达水平与COPD稳定期患者认知功能障碍密切相关。血清lipocalin-2水平检测可能成为COPD患者出现认知功能障碍的一个重要诊断指标。