Active cognitive lifestyle associates with cognitive recovery and a reduced risk of cognitive decline

Education and lifestyle factors linked with complex mental activity are thought to affect the progression of cognitive decline. Collectively, these factors can be combined to create a cognitive reserve or cognitive lifestyle score. This study tested the association between cognitive lifestyle score and cognitive change in a population-based cohort of older persons from five sites across England and Wales. Data came from 13,004 participants of the Medical Research Council Cognitive Function and Ageing Study who were aged 65 years and over. Cognition was assessed at multiple waves over 16 years using the Mini-Mental State Examination. Subjects were grouped into four cognitive states (no impairment, slight impairment, moderate impairment, severe impairment) and cognitive lifestyle score was assessed as a composite measure of education, mid-life occupation, and current social engagement. A multi-state model was used to test the effect of cognitive lifestyle score on cognitive transitions. Hazard ratios for cognitive lifestyle score showed significant differences between those in the upper compared to the lower tertile with a more active cognitive lifestyle associating with: a decreased risk of moving from no to slight impairment (0.58, 95% CI (0.45, 0.74)); recovery from a slightly impaired state back to a non-impaired state (2.93 (1.35, 6.38)); but an increased mortality risk from a severely impaired state (1.28 (1.12, 1.45)). An active cognitive lifestyle is associated with a more favorable cognitive trajectory in older persons. Future studies would ideally incorporate neuroradiological and neuropathological data to determine if there is causal evidence for these associations.     

Multiple cognitive deficits in amnestic mild cognitive impairment

OBJECTIVE: To determine if more widespread cognitive deficits are present in a narrowly defined group of patients with the amnestic form of mild cognitive impairment (MCI). METHODS: From a larger sample of patients clinically diagnosed as meeting the criteria of Petersen et al. for amnestic MCI, we selected 22 subjects who had Clinical Dementia Rating scores of zero on all domains besides memory and orientation. These MCI subjects with presumably isolated memory impairments were compared to 35 age-matched normal controls and 33 very mild Alzheimer's disease (AD) patients on a battery of neuropsychological tests. RESULT: In addition to the expected deficits in episodic memory, the amnestic MCI group performed less well than the controls but better than the AD group on design fluency, category fluency, a set shifting task and the Stroop interference condition. Over half the amnestic MCI group (vs. none of the normal controls) scored at least 1 standard deviation below control means on 4 or more of the nonmemory cognitive tasks. CONCLUSIONS: Isolated memory impairment may be fairly uncommon in clinically diagnosed amnestic MCI patients, even when the criteria for amnestic MCI are fairly narrow. Additional cognitive impairments are likely to include fluency and executive functioning. These more diffuse deficits argue for comprehensive cognitive assessments, even when the patient and family are reporting only memory decline, and are consistent with the increase in attention paid to the heterogeneity of MCI.     

Mild cognitive impairment and cognitive reserve in Parkinson's disease

Patients with Parkinson’s disease (PD) typically present with motor symptoms, but non-motor symptoms, including cognitive impairment, autonomic dysfunction and neuropsychiatric symptoms, are usually also present, when looked for carefully. The objective of this paper is to provide an up-to-date, comprehensive review of two undecided issues about cognitive impairment in PD patients without dementia: the concept of Mild Cognitive Impairment (MCI) and the concept of Cognitive Reserve (CR). Empirical findings support the value of the concept of MCI in this population, from the early untreated stages onwards. Further studies are needed to establish 1) the clinical-neuroimaging characteristics of MCI subtypes in PD, in comparison to those MCI subtypes in patients without PD; 2) whether different types of MCI in PD are associated with different rates of cognitive decline during the progression of the disease. Preliminary empirical evidence also shows that education might exert a protective effect on cognitive decline in PD and that less educated subjects are at increased risk for developing dementia, lending support to the CR hypothesis, in this population as well. Further studies are necessary to investigate how CR modulates cognitive decline in PD and other frontal-subcortical disorders, e.g. by identifying possible differential effects of CR on different cognitive domains.     

MMSE和MoCA在不同类型轻度认知障碍筛查中的应用

目的探讨简易精神状态量表(MMSE)和蒙特利尔认知评估量表(Mo CA)在遗忘型轻度认知障碍(a MCI)和轻度血管性认知障碍(m VCI)患者中的应用。方法从2012年3月至2015年3月本科收治的年龄60~80岁近200例患者中筛选出a MCI组42例,m VCI组50例,采用分组对照研究,所有患者经过临床痴呆评定量表(CDR)和日常生活能力量表(ADL)评估与接受Mo CA量表中文版和MMSE量表进行认知功能评估。Mo CA与MMSE的评估间隔1h以上,在同一天进行。结果两组患者性别构成比、年龄及受教育程度间差异均无统计学意义(P>0.05)。MMSE量表测评两组间差异无统计学意义(P>0.05)。两组间MMSE分项比较,除a MCI组延迟回忆得分低于m VCI组(P<0.05)外,其余各分项得分无显著性差异(P>0.05)。m VCI组患者Mo CA总分较a MCI组水平低,差异有统计学意义(P<0.05)。两组间Mo CA分项比较,m VCI组视空间执行功能、注意力与计算各项得分低于a MCI组,差异有统计学意义(P<0.05)。a MCI组延迟回忆得分低于m VCI组,差异有统计学意义(P<0.05)。余各分项得分两组间无显著性差异(P>0.05)。m VCI组患者在交替连线、立方体画图及指针得分均低于a MCI组,差异有统计学意义(P<0.05)。相关性分析显示MMSE与Mo CA评分呈正相关关系,a MCI患者中相关系数为0.861,m VCI患者中相关系数为0.762,差异均有统计学意义(P<0.05)。结论 m VCI患者存在包括视空间执行功能、注意力及计算力等多个领域认知功能的损害,与a MCI患者相比,执行功能受损更明显。Mo CA是筛查a MCI及m VCI的一个简便、有效的工具,敏感性高于MMSE,尤其适于对m VCI患者的早期筛查。     

The cognitive laterality battery: tests of specialized cognitive function

The Cognitive Laterality Battery of neuropsychological tests is described and normative data and statistics are presented. Selection of tests was based on converging evidence from studies on patients with unilateral cerebral lesions, complete forebrain commissurotomy, and on normal subjects suggesting that visuospatial skills are primarily related to the right hemisphere while verbal and sequential skills are primarily related to the left. Factor analyses confirmed the dichotomy of the test choices. It is suggested that test results on individuals be interpreted as a cognitive profile defining the relative performance of specialized functions rather than the relative right or hemisphere locations. Previous studies with the CLB are described.     

Intraindividual cognitive decline using a brief computerized cognitive screening test

BackgroundProgressive intraindividual decline in memory and cognition is characteristic of dementia and may be useful in detecting very early Alzheimer’s disease pathology.MethodsThis study evaluated the slopes of cognitive performance over a 12-month period in 263 healthy, community-dwelling, adult volunteers aged ≥50 years. Participants completed a brief computerized battery of cognitive tests (CogState) at baseline and during 3-, 6-, 9-, and 12-month follow-up assessments. Linear mixed models were used to estimate age-adjusted mean slopes and 95% confidence intervals of change for each of the cognitive measures.ResultsBy defining age-adjusted mean slopes, and 95% confidence intervals for a measure of episodic memory, individuals with greater than expected decline (equal to or lower than the fifth percentile level of decline) were identified. From these, four individuals completed a full medical, neurologic, and neuropsychological evaluation, with none of them fulfilling criteria for mild cognitive impairment, but three (75%) having positive amyloid-positron emission tomographic scans.ConclusionsIntraindividual decline in cognitive performance can be detected in otherwise healthy, community-dwelling, older persons, and this may deserve further study as a potential indicator of early Alzheimer’s disease pathology.     

Estrogen and cognitive functioning in men with mild cognitive impairment

Although men do not experience an abrupt cessation of gonadal hormone production at midlife as do women, levels of testosterone (T) decrease gradually with aging. Because estradiol (E₂) arises mainly from the conversion of T in men, the availability of E₂ also decreases with increasing age. In randomized clinical trials, E₂ replacement therapy has been shown to maintain aspects of cognition in postmenopausal women, specifically with regard to verbal memory. The present prospective, randomized, cross-over trial is being undertaken in order to determine whether E₂ will enhance verbal memory in men with Mild Cognitive Impairment (MCI). Men with MCI will randomly receive E₂ or placebo for the first 3 mo of treatment and will then be crossed-over to the other treatment for an additional 3 mo. A battery of neuropsychological tests will be administered at pretreatment and, again, following each 3-mo treatment phase. It is hypothesized that elderly men with MCI will perform better on tests of explicit memory when they are being treated with E₂ compared to their performance under placebo conditions.     

Hippocampal shape and cognitive performance in amnestic mild cognitive impairment

Previous studies have carried out hippocampal shape analysis of amnestic mild cognitive impairment (aMCI) patients using automated segmentation techniques. However, the relationships between hippocampal deformations and various episodic memory impairments were not clear. The aim of this study was to investigate hippocampal shape changes and their relationships with various episodic memory impairments in aMCI. Hippocampal volumes and deformations were compared between the aMCI and the controls. In addition, we explored the correlation pattern between hippocampal deformations and cognitive dysfunctions in aMCI using a comprehensive neuropsychological battery. Patients with aMCI exhibited significant hippocampal deformations in the right cornu ammonis 1 (CA1) and subiculum areas compared with healthy individuals. Significant correlations were observed between constructional recall scores and the right CA1 and subiculum areas in aMCI. Verbal delayed recall scores were also significantly correlated with the left CA1 and subiculum areas in aMCI. This study was the first to explore the relationships between hippocampal deformations and various types of cognitive performances in aMCI. These structural changes in the hippocampal CA1 and subiculum areas might be at the core of underlying neurobiological mechanisms of hippocampal dysfunction and their relevance to verbal and visuospatial delayed recall in aMCI.     

Clinical referral patterns and cognitive profile in mild cognitive impairment

BACKGROUND: There is current interest in exploring the different subtypes of mild cognitive impairment (MCI), in terms of both their epidemiology and their cognitive profile. AIMS: To examine the frequency of MCI subtypes presenting to a memory clinic and to document detailed neuropsychological profiles of patients with the amnestic subtype. METHOD: Consecutive tertiary referrals (n=187) were psychiatrically evaluated; 45 patients met criteria for amnestic mild cognitive impairment (aMCI). A subgroup of 33 patients with aMCI as well as 21 healthy controls took part in a thorough neuropsychological examination. RESULTS: Of the patients who were examined in greater neuropsychological detail, ten had pure aMCI (none with visual memory impairment only). Fifteen met criteria for non-amnestic MCI. Fifteen had normal neuropsychological profiles. Using more than one test increased sensitivity to detect episodic memory impairment. CONCLUSIONS: Amnestic MCI is an important diagnosis in secondary and tertiary memory clinics. There is scope to improve the efficacy and sensitivity of the clinical assessment of this impairment.     

认知功能电话问卷修订版在认知功能损害早期测查中的应用

目的　检测认知功能电话问卷修订版 (TICS m)在认知功能损害早期测查时的信度和效度。方法　认知功能损害组患者 64例,对照组为社区健康老人 52名。由 2名神经科医师独立、盲法检查TICS m。做操作者工作特征(ROC)曲线,计算诊断效度。结果　TICS m各部分面访与电话访问的Pearson相关系数在 0 79~0 96之间,重测信度Pearson相关系数在 0 89 ~0 98之间。TICS m诊断痴呆( <28分)和轻度认知功能损害( <33分)的敏感性分别为 99%和 89%,特异性为 90%和92%,优于细微精神状态检查(MMSE)。TICS m总分和记忆力部分的敏感性较高。结论　TICS m具有很好的信度和效度,可用于认知功能损害早期的临床和流行病学筛查。TICS m对早期认知功能损害的诊断效度优于MMSE。     

Longitudinal metabolic and cognitive changes in mild cognitive impairment patients

Advancements in clinical therapies have identified the need for biomarkers of early Alzheimer disease that distinguish the earliest stages of pathology and target those patients who are likely to gain the most benefit. The aim of this study was to characterize the longitudinal metabolic changes measured by 1H magnetic resonance spectroscopy in correlation to neuropsychologic indices of episodic memory, attention and mental processing speed, language facility, and executive function in subjects with mild cognitive impairment (MCI). Quantitative 1H magnetic resonance spectroscopy of the posterior cingulate gyrus was performed and repeated at 11.56+/-4.3 months. N-acetyl aspartate (NAA), total choline (Cho), total creatine (Cr), myo-inositol (mI), and glutamate/glutamine (Glx) metabolite levels were measured, corrected for cerebrospinal fluid dilution, and ratios calculated in MCI and cognitively normal subjects. In the first study, MCI subjects showed lower NAA levels, NAA/Cho, and NAA/mI ratios and increased Cho/Cr and mI/Cr compared with controls. In the follow-up study, 36% of the MCI subjects [atypical MCI (atMCI)] showed interval increases in NAA, Cr, and Glx levels compared with 64% of MCI subjects (typical MCI) who showed an interval decrease in NAA, Cr, and Glx. Both MCI subgroups had higher Clinical Dementia Rating scores and lower scores on episodic memory, phonemic, and semantic word fluency tasks, compared with controls. The annualized rate of change in metabolic and cognitive status did not differ between normal aging and MCI subjects. atMCI subjects showed significant negative correlations between metabolite levels and executive function task scores, with NAA/mI showing a significant positive correlation with phonemic and semantic word fluency. There were no significant correlations between metabolite levels and cognitive performance in tMCI subjects; however, NAA/mI and mI/Cr were negatively correlated with executive function tasks. These results indicate 2 distinct evolving metabolite profiles that correlate with changes in executive function and can be used to differentiate MCI from normal aging.     

Relationship of leukoaraiosis to cognitive decline and cognitive aging.

OBJECTIVE: Leukoaraiosis (LA) is a common finding on MRI scans of the elderly. However, its exact relationship to cognitive decline and dementia is in dispute. Because LA involves the paracallosal white matter, we sought to determine if LA, uncomplicated by ischemic lesions or complaints of cognitive impairment, is associated with cognitive loss or difficulties with interhemispheric integration of behavioral functions. METHODS: Two hundred fifty-seven MRI scans with deep white matter changes were screened. After a chart review, 38 patients had uncomplicated LA, and 31 gave informed consent to undergo cognitive and behavioral testing. RESULTS: LA severity was not related to any of the cognitive or behavioral assessments. However, some dependent measures showed medium effect sizes that were in keeping with published findings, indicating that LA has a marginal impact on cognition. In comparison, robust relationships with age were found for certain tasks, suggesting that our cohort size was sufficient to detect meaningful clinical relationships. CONCLUSION: Based on statistical interpretations using effect sizes, LA severity may be better viewed as a biomarker for physiological brain aging that is in advance of chronological age, leaving the elderly individual at greater risk for developing dementia.     

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.