Mayo older americans normative studies: factor analysis of an expanded neuropsychological battery

Inventory of sensory, emotional, and cognitive reserve (SECri): Proposal of a new instrument and preliminary data

A new model of reserve, the Sensory, Emotional, and Cognitive Reserve (SEC) model, has been recently proposed, but so far this model has not been operationalized in instruments to evaluate the different domains of the reserve. This study introduces the SEC reserve inventory (SECri) along with preliminary data obtained from a study involving 57 adults, aged 35 and older. The SECri assesses the SEC domains using specific proxies: (a) sensory reserve (SR) through sensory acuity and sensory perception proxies; (b) emotional reserve (ER) through life events, resilience, and emotional regulation proxies; and (c) cognitive reserve (CR) through education, occupation, socioeconomic status, bilingualism, leisure activities, and personality traits proxies. Key features of SECri include self- and informant-report forms, fine-grained response scales, and the evaluation of reserve development across the lifespan. Findings on the acceptability, convergent validity between SECri domains and validated tests for the same constructs, internal consistency of each domain, and predictive validity of Montreal Cognitive Assessment scores support further research with this inventory. Future studies should consider determining SECri's psychometric properties in clinical and subclinical conditions to evaluate its prognostic value in cases of neurocognitive decline.

Impact of Stimulation Frequency on Verbal Fluency Following Bilateral Subthalamic Nucleus Deep Brain Stimulation in Parkinson's Disease

OBJECTIVE

The effects of stimulation frequency on verbal fluency (VF) following subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) are not well understood. The present study examines the impact stimulation frequency has on VF following bilateral STN-DBS in PD.

METHODS

Prospective study of 38 consecutive patients with PD with low frequency STN-DBS (LFS) (n = 10) and high frequency STN-DBS (HFS) (n = 14), and a non-operated PD control group consisting of patients with fluctuating response to dopaminergic medication (n = 14) homogeneous in age, education, disease duration, and global cognitive function. Patients were evaluated on VF tasks (letter, semantic, action verbs, alternating). A one-way analysis of variance (ANOVA) was conducted to assess distinctions between groups. Pre- and post-surgical comparisons of fluencies were performed for operated groups. A mixed ANOVA was applied to the data to evaluate the interaction between treatment (HFS vs. LFS) and time (pre- vs. post-surgery). Strategy use (clustering and switching) was evaluated.

RESULTS

Semantic and letter fluency performance revealed significant differences between HFS and LFS groups. Pre- and post-surgical comparisons revealed HFS negatively affected letter, semantic, and action fluencies, but LFS had no effect on VF. No interaction effect or main effect of treatment was found. Main effect of time was significant for semantic and action fluencies indicating a decrease in postoperative fluency performance. Patients with LFS produced larger average cluster sizes than patients with HFS.

CONCLUSION

LFS may be less detrimental to VF, but these findings suggest that VF decline following STN-DBS is not caused by stimulation frequency alone.

Does neuropsychological intraindividual variability index cognitive dysfunction, an invalid presentation, or both? Preliminary findings from a mixed clinical older adult veteran sample

INTRODUCTION

Intraindividual variability across a battery of neuropsychological tests (IIV-dispersion) can reflect normal variation in scores or arise from cognitive impairment. An alternate interpretation is IIV-dispersion reflects reduced engagement/invalid test data, although extant research addressing this interpretation is significantly limited.

METHOD

We used a sample of 97 older adult (mean age: 69.92), predominantly White (57%) or Black/African American (34%), and predominantly cis-gender male (87%) veterans. Examinees completed a comprehensive neuropsychological battery, including measures of reduced engagement/invalid test data (a symptom validity test [SVT], multiple performance validity tests [PVTs]), as part of a clinical evaluation. IIV-dispersion was indexed using the coefficient of variance (CoV). We tested 1) the relationships of raw scores and "failures" on SVT/PVTs with IIV-dispersion, 2) the relationship between IIV-dispersion and validity/neurocognitive disorder status, and 3) whether IIV-dispersion discriminated the validity/neurocognitive disorder groups using receiver operating characteristic (ROC) curves.

RESULTS

IIV-dispersion was significantly and independently associated with a selection of PVTs, with small to very large effect sizes. Participants with invalid profiles and cognitively impaired participants with valid profiles exhibited medium to large (d = .55-1.09) elevations in IIV-dispersion compared to cognitively unimpaired participants with valid profiles. A non-significant but small to medium (d = .35-.60) elevation in IIV-dispersion was observed for participants with invalid profiles compared to those with a neurocognitive disorder. IIV-dispersion was largely accurate at differentiating participants without a neurocognitive disorder from invalid participants and those with a neurocognitive disorder (areas under the Curve [AUCs]=.69-.83), while accuracy was low for differentiating invalid participants from those with a neurocognitive disorder (AUCs=.58-.65).

CONCLUSIONS

These preliminary data suggest IIV-dispersion may be sensitive to both neurocognitive disorders and compromised engagement. Clinicians and researchers should exercise due diligence and consider test validity (e.g. PVTs, behavioral signs of engagement) as an alternate explanation prior to interpretation of intraindividual variability as an indicator of cognitive impairment.

Small effects of olfactory identification and discrimination on global cognitive and executive performance over 1 year in aging people without a history of age-related cognitive impairment

Olfactory and cognitive performance share neural correlates profoundly affected by physiological aging. However, whether odor identification and discrimination scores predict global cognitive status and executive function in healthy older people with intact cognition is unclear. Therefore, in the present study, we set out to elucidate these links in a convenience sample of 204 independently living, cognitively intact healthy Czech adults aged 77.4 ± 8.7 (61-97 years) over two waves of data collection (one-year interval). We used the Czech versions of the Montreal Cognitive Assessment (MoCA) to evaluate global cognition, and the Prague Stroop Test (PST), Trail Making Test (TMT), and several verbal fluency (VF) tests to assess executive function. As a subsidiary aim, we aimed to examine the contribution of olfactory performance towards achieving a MoCA score above vs. below the published cut-off value. We found that the MoCA scores exhibited moderate associations with both odor identification and discrimination. Furthermore, odor identification significantly predicted PST C and C/D scores. Odor discrimination significantly predicted PST C/D, TMT B/A, and standardized composite VF scores. Our findings demonstrate that olfaction, on the one hand, and global cognition and executive function, on the other, are related even in healthy older people.

Current Understanding of Verbal Fluency in Alzheimer's Disease: Evidence to Date

Since their development, verbal fluency tests (VFTs) have been used extensively throughout research and in clinical settings to assess a variety of cognitive functions in diverse populations. In Alzheimer's disease (AD), these tasks have proven particularly valuable in identifying the earliest forms of cognitive decline in semantic processing and have been shown to relate specifically to brain regions associated with the initial stages of pathological change. In recent years, researchers have developed more nuanced techniques to evaluate verbal fluency performance, extracting a wide range of cognitive metrics from these simple neuropsychological tests. Such novel techniques allow for a more detailed exploration of the cognitive processes underlying successful task performance beyond the raw test score. The versatility of VFTs and the richness of data they may provide, in light of their low cost and speed of administration, therefore, highlight their potential value both in future research as outcome measures for clinical trials and in a clinical setting as a screening measure for early detection of neurodegenerative diseases.

Visuoconstructional Abilities of Patients With Subjective Cognitive Decline, Mild Cognitive Impairment and Alzheimer's Disease

BACKGROUND

Via the Vienna Visuoconstructional Test 3.0 (VVT 3.0) delayed recall we combined the assessment of visuoconstructive abilities and memory and investigated the test's potential to support diagnostic processes, including staging and the elaboration of a cognitive profile.

METHODS

We retrospectively analysed the data of 368 patients of the Department of Neurology, Medical University of Vienna, between 04/2014 and 10/2020 that had performed the VVT 3.0. Our sample involved 70 healthy controls (HC), 29 patients with subjective cognitive decline (SCD), 154 patients with mild cognitive impairment (MCI) and 115 patients with Alzheimer's disease (AD). We investigated the differences in the VVT 3.0 scores, as well as the VVT's ability to differentiate between AD and nonAD by calculating receiver-operating-characteristic (ROC) curves, ideal cut-offs and a logistic regression model.

RESULTS

Results stated that the VVT 3.0 delayed recall scores were able to differentiate between all diagnostic groups, respectively, except HC-SCD and SCD-MCI. The ROC analyses determined an AUC of 0.890, 95% CI [0.855; 0.925], P < .001, and the ideal cut-off at 29.5 points that maximised sensitivity at 0.896 and specificity at 0.81. The logistic regression model classified 83.4% of AD patients correctly and delivered a significant Cohen's Kappa of 0.619 (P < .001).

CONCLUSION

As the VVT 3.0 revealed satisfactory values of diagnostic accuracy in our sample, it could enrich clinical diagnosing. However, for more clarity about its informative value in other populations, there remains a need for future studies with other samples.

Semantic fluency deficits and associated brain activity in Parkinson's disease with mild cognitive impairment

People living with Parkinson's disease (PD) with poor verbal fluency have an increased risk of developing dementia. This study examines the neural mechanisms underpinning semantic fluency deficits in patients with PD with mild cognitive impairment (PD-MCI) compared to those without MCI (PD-NC) and control participants without PD (non-PD). Thirty-seven (37) participants with PD completed a cognitive assessment battery to identify MCI (13 PD-MCI). Twenty sex- and age-matched non-PD patients also participated. Participants were scanned (3T Siemens PRISMA) while performing semantic fluency, semantic switching, and automatic speech tasks. The number of responses and fMRI data for semantic generation and semantic switching were analyzed. Participants also completed a series of verbal fluency tests outside the scanner, including letter fluency. Participants with PD-MCI performed significantly worse than PD-NC and non-PD participants during semantic fluency and semantic switching tasks. PD-MCI patients showed greater activity in the right angular gyrus than PD-NC and non-PD patients during semantic switching. Increased right angular activity correlated with worse verbal fluency performance outside the scanner. Our study showed that the PD-MCI group performed worse on semantic fluency than either the PD-NC or non-PD groups. Increased right angular gyrus activity in participants with PD-MCI during semantic switching suggests early compensatory mechanisms, predicting the risk of future dementia in PD.

Assessing visuo-constructive functions in patients with subjective cognitive decline, mild cognitive impairment and Alzheimer’s disease with the Vienna Visuo-Constructional Test 3.0 (VVT 3.0)

Background

Visuo-Constructive functions have considerable potential for the early diagnosis and monitoring of disease progression in Alzheimer’s disease.

Objectives

Using the Vienna Visuo-Constructional Test 3.0 (VVT 3.0), we measured visuo-constructive functions in subjective cognitive decline (SCD), mild cognitive impairment (MCI), Alzheimer’s disease (AD), and healthy controls to determine whether VVT performance can be used to distinguish these groups.

Materials and methods

Data of 671 participants was analyzed comparing scores across diagnostic groups and exploring associations with relevant clinical variables. Predictive validity was assessed using Receiver Operator Characteristic curves and multinomial logistic regression analysis.

Results

We found significant differences between AD and the other groups. Identification of cases suffering from visuo-constructive impairment was possible using VVT scores, but these did not permit classification into diagnostic subgroups.

Conclusions

In summary, VVT scores are useful indicators for visuo-constructive impairment but face challenges when attempting to discriminate between several diagnostic groups.

Distributed functional connectivity predicts neuropsychological test performance among older adults

Neuropsychological test is an essential tool in assessing cognitive and functional changes associated with late-life neurocognitive disorders. Despite the utility of the neuropsychological test, the brain-wide neural basis of the test performance remains unclear. Using the predictive modeling approach, we aimed to identify the optimal combination of functional connectivities that predicts neuropsychological test scores of novel individuals. Resting-state functional connectivity and neuropsychological tests included in the OASIS-3 dataset (n = 428) were used to train the predictive models, and the identified models were iteratively applied to the holdout internal test set (n = 216) and external test set (KSHAP, n = 151). We found that the connectivity-based predicted score tracked the actual behavioral test scores (r = 0.08-0.44). The predictive models utilizing most of the connectivity features showed better accuracy than those composed of focal connectivity features, suggesting that its neural basis is largely distributed across multiple brain systems. The discriminant and clinical validity of the predictive models were further assessed. Our results suggest that late-life neuropsychological test performance can be formally characterized with distributed connectome-based predictive models, and further translational evidence is needed when developing theoretically valid and clinically incremental predictive models.

Quantitative and Qualitative Analysis of Verb Fluency Performance in Individuals With Probable Alzheimer's Disease and Healthy Older Adults

Purpose To date, verb fluency tasks have been mainly analyzed quantitatively for individuals with dementia. Qualitative analysis, however, such as examining the semantic and psycholinguistic content of the responses might further inform researchers and clinicians about patients' cognitive and linguistic status. Therefore, the current study examined psycholinguistic and lexical characteristics of verb fluency responses in individuals with probable Alzheimer's disease (pAD) and healthy older adults to delineate qualitative and quantitative differences between the two groups. Method The verb fluency responses from participants with pAD (amnestic type) were compared to those from age- and education-matched healthy older adults. The responses were analyzed with respect to the number and proportion of correct responses, word frequency, age of acquisition, phoneme and syllable length, and neighborhood density. The verb responses were also categorized into mental state verbs and action verbs. Additionally, a battery of cognitive-linguistic tests was administered, and for each group, relationships between correct verb fluency responses and other cognitive-linguistic skills were investigated using correlation and regression analyses. Results Similar to previous findings regarding noun retrieval in dementia, the results revealed that individuals with pAD not only produced fewer correct verb fluency responses but also generated little to no mental state verbs compared to the control group. The group with pAD also produced verbs with shorter phoneme and syllable lengths, higher word frequency, and earlier age of acquisition ratings relative to the healthy older adults. The number of correct verb fluency responses was mainly predicted by a reading comprehension score in the pAD group and a nonverbal fluency test score in the healthy group. Conclusion The current quantitative and qualitative findings add support to the contention that lexical-semantic impairments underlie word retrieval problems in pAD and such difficulties present in generative naming paradigms and also across grammatical categories.

Cognitive and neuropsychological examination of the elderly

Neuropsychological assessment plays a prominent role in the evaluation and care of patients with neurodegenerative diseases throughout the dynamic course of disease. As a biomarker of disease, neuropsychological measurement can distinguish normal from pathologic aging processes. Further, neuropsychological data can help distinguish and classify underlying pathologies in dementing diseases, augmenting imaging and biofluid markers in this area. Neuropsychological data can predict increased or reduced risk for dementia conferred by multiple factors, and describe disease trajectory in affected individuals. Cognitive evaluation can also estimate and address functional outcomes that are most important to patients and their loved ones and that are clinically relevant to diagnostic staging. In informing intervention and patient care needs, areas of cognitive weakness highlight targets for support/intervention, while areas of cognitive strength can be capitalized upon to modify the clinical course of disease. These functions can be accomplished through the complementary use of brief screening tools and comprehensive test batteries. However, for neuropsychological data to serve these functions, it is critical to understand neuropsychological test properties and nondisease factors that can account for variance in test performance. This chapter concludes with directions for future research.

An Examination of Semantic Impairment in Amnestic MCI and AD: What Can We Learn From Verbal Fluency?

Introduction

The Verbal Fluency Test (VF) is commonly used in neuropsychology. Some studies have demonstrated a marked impairment of semantic VF compared to phonemic VF in Alzheimer’s disease (AD). Since amnestic Mild Cognitive Impairment (aMCI) is associated with increased risk of conversion to incident AD, it is relevant to examine whether a similar impairment is observed in this population. The objective of the present empirical study is to compare VF performance of aMCI patients to those of AD and elderly controls matched one-to-one for age and education.

Method

Ninety-six participants divided into three equal groups (N = 32: AD, aMCI and Controls) were included in this study. Participants in each group were, on average, 76 years of age and had 13 years of education. A repeated measures ANOVA with the Group (AD, aMCI, NC) as between-subject factor and the Fluency condition (“P” and “animals”) as within-subject factor was performed. T-tests and simple ANOVAs were also conducted to examine the interaction.

Results

There was a significant interaction between the groups and the verbal fluency condition. In AD, significantly fewer words were produced in both conditions. In contrast, participants with aMCI demonstrated a pattern similar to controls in the phonemic condition, but generated significantly fewer words in the semantic condition.

Conclusion

These results indicate a semantic memory impairment in aMCI revealed by a simple, commonly-used neuropsychological test. Future studies are needed to investigate if semantic fluency deficits can help predict future conversion to AD.

Screening for dementia with the Vienna Visuo-Constructional Test 3.0 screening (VVT 3.0 screening)

BACKGROUND

Visuo-constructive functions are an important cognitive domain for the diagnosis and early detection of dementia. Using the Vienna Visuo-Constructional Test 3.0 Screening (VVT 3.0 Screening), we assessed visuo-constructive performance in subjective cognitive decline (SCD), mild cognitive impairment (MCI), Alzheimer's disease (AD), and healthy control (HC) groups to determine whether VVT scores can be used to distinguish the mentioned diagnostic groups and predict disease progression to more advanced stages.

METHODS

We analyzed the data of 422 patients referred to the Department of Neurology, Medical University of Vienna, for assessment of neurocognitive status. We also examined 110 of these patients in a follow-up with regard to stability of performance and disease progression. We compared VVT performance across diagnostic groups and explored associations with relevant sociodemographic and clinical variables. Predictive validity was assessed using receiver operator characteristic (ROC) curves and multinomial logistic regression analyses.

RESULTS

We found that most diagnostic groups differed significantly regarding VVT scores. These were shown to reliably identify cases suffering from visuo-constructive impairment but were not sufficient for classification into all diagnostic groups. Progression to more advanced disease stages could not be reliably predicted using VVT scores, possibly because subsamples of progressors were quite small.

CONCLUSION

VVT scores are useful indicators for identifying visuo-constructive impairment but are limited by factors such as similar disease manifestations when used to discriminate between several diagnostic groups. The same factors complicate the use of VVT scores for predicting disease progression to more advanced stages.

Cognitive impairment in Parkinson's disease: a report from a multidisciplinary symposium on unmet needs and future directions to maintain cognitive health

People with Parkinson's disease (PD) and their care partners frequently report cognitive decline as one of their greatest concerns. Mild cognitive impairment affects approximately 20-50% of people with PD, and longitudinal studies reveal dementia in up to 80% of PD. Through the Parkinson's Disease Foundation Community Choice Research Award Program, the PD community identified maintaining cognitive function as one of their major unmet needs. In response, a working group of experts across multiple disciplines was organized to evaluate the unmet needs, current challenges, and future opportunities related to cognitive impairment in PD. Specific conference goals included defining the current state in the field and gaps regarding cognitive issues in PD from patient, care partner, and healthcare professional viewpoints; discussing non-pharmacological interventions to help maintain cognitive function; forming recommendations for what people with PD can do at all disease stages to maintain cognitive health; and proposing ideas for how healthcare professionals can approach cognitive changes in PD. This paper summarizes the discussions of the conference, first by addressing what is currently known about cognitive dysfunction in PD and discussing several non-pharmacological interventions that are often suggested to people with PD. Second, based on the conference discussions, we provide considerations for people with PD for maintaining cognitive health and for healthcare professionals and care partners when working with people with PD experiencing cognitive impairment. Furthermore, we highlight key issues and knowledge gaps that need to be addressed in order to advance research in cognition in PD and improve clinical care.

Decreased Cognitive Functioning After Electroconvulsive Therapy Is Related to Increased Hippocampal Volume: Exploring the Role of Brain Plasticity

OBJECTIVE

Electroconvulsive therapy (ECT) is still the most effective treatment of severe and therapy-refractory major depressive disorder. Cognitive side effects are the major disadvantage of ECT. Cognitive deficits are generally temporary in nature and may be mediated by the hippocampus. Recent studies have shown a temporary increase in hippocampal volume and a temporary decrease in cognitive functioning post-ECT compared with pre-ECT. This study investigates whether these volumetric changes are related to changes in cognitive functioning after ECT.

METHODS

Nineteen medication-free patients with treatment-resistant major depressive disorder underwent a whole-brain magnetic resonance imaging scan and a neuropsychological examination (including the Rey auditory verbal learning task, Wechsler Memory Scale Visual Reproduction, fluency, Trail Making Task) within 1 week before and within 1 week after the course of ECT. Electroconvulsive therapy was administered twice a week bitemporally with a brief pulse. A matched healthy control group (n = 18) received the same neuropsychological examination and at a similar interval to that of the patients.

RESULTS

Hippocampal volumes increased significantly from pretreatment to posttreatment in patients. Mean performance on cognitive tasks declined, or remained stable, whereas performance in controls generally improved because of retesting effects. The increase in hippocampal volume was related to changes in cognitive performance, indicating that this increase co-occurred with a decrease in cognitive functioning.

CONCLUSIONS

Our findings tentatively suggest that the temporal increase in hippocampal volume after treatment, which may result from neurotrophic processes and is thought to be crucial for the antidepressive effect, is also related to the temporary cognitive side effects of ECT.

The independent influences of age and education on functional brain networks and cognition in healthy older adults

Healthy aging is accompanied by a constellation of changes in cognitive processes and alterations in functional brain networks. The relationships between brain networks and cognition during aging in later life are moderated by demographic and environmental factors, such as prior education, in a poorly understood manner. Using multivariate analyses, we identified three latent patterns (or modes) linking resting-state functional connectivity to demographic and cognitive measures in 101 cognitively normal elders. The first mode (P = 0.00043) captures an opposing association between age and core cognitive processes such as attention and processing speed on functional connectivity patterns. The functional subnetwork expressed by this mode links bilateral sensorimotor and visual regions through key areas such as the parietal operculum. A strong, independent association between years of education and functional connectivity loads onto a second mode (P = 0.012), characterized by the involvement of key hub regions. A third mode (P = 0.041) captures weak, residual brain-behavior relations. Our findings suggest that circuits supporting lower level cognitive processes are most sensitive to the influence of age in healthy older adults. Education, and to a lesser extent, executive functions, load independently onto functional networks-suggesting that the moderating effect of education acts upon networks distinct from those vulnerable with aging. This has important implications in understanding the contribution of education to cognitive reserve during healthy aging. Hum Brain Mapp 38:5094-5114, 2017. © 2017 Wiley Periodicals, Inc.

Semantic verbal fluency impairment is detectable in patients with subjective cognitive decline

Patients with subjective cognitive decline (SCD) are at higher risk for conversion to dementia due to Alzheimer's disease (AD). Semantic verbal fluency (SVF) seems to be impaired in the early stages of AD. The goal of the present study was to identify the discriminative potential of verbal fluency (VF) in patients with SCD to show if very early signs of cognitive decline may be detected in SCD. We examined 93 normal controls (NC) and 61 participants with SCD. Each participant was administered a comprehensive neuropsychological battery. All participants underwent tests of VF: phonemic verbal fluency (PVF), letters K and P and SVF (animals and vegetables categories). In addition to the total score, two 30-second intervals, and clustering and switching indices in SVF were evaluated. SCD generated fewer words in the total score and 30- to 60-second interval in vegetables category and they performed more switches in animals category. There was no significant difference between the SCD and the NC groups in all other VF measures. Quantitative measures of SVF (a decreased number of vegetables) as well as qualitative measures were detected in SCD group and could be considered as an early neuropsychological marker of subtle cognitive impairment.

The impact of depressive symptoms on health-related quality of life in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease

BACKGROUND

Health-related quality of life (HRQOL) is an important issue in the context of dementia care. The purpose of this study was to investigate the association between HRQOL and depressive symptoms in patients with subjective cognitive decline (SCD) and subtypes of mild cognitive impairment (MCI) and Alzheimer´s disease (AD).

METHODS

In this cross-sectional, observational study, a control group and four experimental groups (SCD, non-amnestic MCI, amnesticMCI, AD) were compared. Neuropsychological measurers (NTBV) and psychological questionnaires were used for data collection.

RESULTS

The control group scored higher than patients with SCD, naMCI, aMCI, or AD for the Mental Health Component Score (MHCS) of the Short Form of the Health Survey (SF-36). The Physical Health Component Score (PHCS) of the SF-36 differed only between some groups. Furthermore, cognitive variables were more strongly associated with the physical aspects of HRQOL, whereas depressive symptoms were more strongly related with the mental aspects of HRQOL.

CONCLUSIONS

HRQOL and depressive symptoms are closely related in patients with cognitive impairments. Therefore, it is of great importance to assess patients with subjective impairment carefully in terms of depressive symptoms.

Health-Related Quality of Life in Patients with Subjective Cognitive Decline and Mild Cognitive Impairment and its Relation to Activities of Daily Living

BACKGROUND

Health related quality of life (HRQOL) is an important issue in the context of dementia care.

OBJECTIVES

The purpose of this study was to investigate HRQOL in patients with subjective cognitive decline (SCD) and mild cognitive impairment (MCI) and its relation to Activity of Daily Living (ADL).

METHODS

In this cross sectional study, four experimental groups (each n = 98), controls, SCD, naMCI and aMCI, were compared. For data collection, neuropsychological methods (NTBV) and psychological questionnaires (SF-36 and B-ADL) were used. Multivariate analysis of variance was calculated to detect differences in HRQOL between groups. Correlations between HRQOL and ADL were explored.

RESULTS

The dimensions of HRQOL showed mainly consistent differences between the control and the SCD group and MCI subgroups. In almost every dimension of HRQOL, the control group scored higher than subjects with SCD, naMCI, or aMCI. The controls showed low to moderate negative correlations between HQROL and B-ADL in some dimensions of the HRQOL. In the SCD group, low negative correlations with ADL were observed in some HRQOL scales. Low to moderate correlations were found between each scale of the SF-36 and the B-ADL in both MCI subtypes. We found gender differences in HRQOL.

CONCLUSION

In conclusion, we could demonstrate that patients with SCD report reduced quality of life. This knowledge is important to get a better understanding of the individuals with SCD and may pave the way for the development of early intervention.

The Cattell–Horn–Carroll Model of Cognition for Clinical Assessment

The Cattell–Horn–Carroll (CHC) model is a comprehensive model of the major dimensions of individual differences that underlie performance on cognitive tests. Studies evaluating the generality of the CHC model across test batteries, age, gender, and culture were reviewed and found to be overwhelmingly supportive. However, less research is available to evaluate the CHC model for clinical assessment. The CHC model was shown to provide good to excellent fit in nine high-quality data sets involving popular neuropsychological tests, across a range of clinically relevant populations. Executive function tests were found to be well represented by the CHC constructs, and a discrete executive function factor was found not to be necessary. The CHC model could not be simplified without significant loss of fit. The CHC model was supported as a paradigm for cognitive assessment, across both healthy and clinical populations and across both nonclinical and neuropsychological tests. The results have important implications for theoretical modeling of cognitive abilities, providing further evidence for the value of the CHC model as a basis for a common taxonomy across test batteries and across areas of assessment.

Construct Validity of Fluency and Implications for the Factorial Structure of Memory

Fluency is an important construct in clinical assessment and in cognitive taxonomies. In the Cattell–Horn–Carroll (CHC) model, Fluency is represented by several narrow factors that form a subset of the long-term memory encoding and retrieval (Glr) broad factor. The CHC broad classification of Fluency was evaluated in five data sets, and the CHC narrow classification was evaluated in an additional two data sets. The results suggest that Fluency tests are more strongly related to processing speed (Gs) and acquired knowledge (Gc) than to Glr, but Fluency may also be represented as a distinct broad factor. In the two additional data sets with a large number of Fluency tests, the CHC Fluency narrow factors failed to replicate with confirmatory factor analysis. An alternative and simpler narrow structure of Fluency was found, supporting the factorial distinction of semantic versus orthographic Fluency. The results have important implications for the factorial structure of memory, the classification of Fluency tests, and the assessment of Fluency.

Cognitive reserve in multiple sclerosis: Protective effects of education

Background:

Recent data suggest that cognitive reserve modulates the adverse effects of multiple sclerosis (MS) pathology on cognitive functioning; however, the protective effects of education in MS are still unclear.

Objective:

To explore education as an indicator of cognitive reserve, while controlling for demographic, clinical and genetic features.

Methods:

A total of 419 MS patients and 159 healthy comparison (HC) subjects underwent a comprehensive neuropsychological (NP) assessment, and answered the Hospital Anxiety and Depression Scale. Based on the HC data, MS patients’ NP scores were adjusted for sex, age and education; and the estimated 5th percentile (or 95th percentile, when appropriate) was used to identify any deficits. Patients also performed the Mini-Mental State Examination (MMSE); and their human leucocyte antigen HLA-DRB1 and apolipoprotein E ( ApoE) genotypes were investigated.

Results:

Patients with higher education were less likely ( p < 0.05) to have cognitive deficits than those with lower education, even when controlling for other covariates. Other significant predictors of cognitive deficit were: age, Expanded Disability Status Scale (EDSS), Multiple Sclerosis Severity Scale (MSSS), and a progressive course. No significant association was found with the HLA-DRB1*15:01 or ApoE ε4 alleles.

Conclusions:

These results provide support to the use of education as a proxy of cognitive reserve in MS and stress the need to take into account education when approaching cognition in MS.

Intraindividual variability across cognitive tasks as a potential marker for prodromal Alzheimer's disease

Recent studies have shown that increased cognitive intraindividual variability (IIV) across accuracy scores from tests representing different cognitive domains (across-domain IIV) might indicate prodromal Alzheimer’s disease (AD). Although IIV has been proposed to index cognitive control processes, IIV across accuracy scores from cognitive control tasks (within-domain IIV) has not been examined in healthy controls subjects (HCS), mild cognitive impairment (MCI), and AD patients in a single comparative study. This study examines the discriminative properties of within-domain IIV, and across-domain IIV in 149 HCS, 31 MCI, and 26 AD. Three tasks representing different cognitive domains were identified to calculate across-domain IIV. Three other tasks representing cognitive control were identified to calculate within-domain IIV. The intraindividual standard deviation was calculated across accuracy scores. To compare IIV between groups, ANCOVAs with the covariates age, gender, education, and mean performance were computed. IIV scores in general were higher in AD vs. HCS (p < 0.01). Only across-domain IIV was higher in AD vs. MCI (p = 0.001), and only within-domain IIV was higher in MCI vs. HCS (p = 0.05). Within-domain IIV may constitute a cognitive marker for the detection of prodromal AD at the MCI stage, whereas across-domain IIV may detect beginning AD at the MCI stage.

Prevalence of Mild Cognitive Impairment Subtypes in Patients with Parkinson’s Disease – Comparison of two Modes of Classification

Early detection of dementia in Parkinson’s disease is becoming increasingly important. The goal of this study was to establish prevalence of mild cognitive impairment subtypes in Parkinson’s disease using two different modes of mild cognitive impairment classification. Categorizing patients into mild cognitive impairment subtypes according to the minimum mode of mild cognitive impairment classification revealed the following results: three patients (2.5 %) were categorized as cognitively healthy, whereas 117 patients (97.5 %) met the criteria for mild cognitive impairment. When categorizing patients according to the mean mode of mild cognitive impairment classification, 41.7 % of the patients were categorized as cognitively healthy, whereas 58.3 % met the criteria for mild cognitive impairment. Frequency of mild cognitive impairment varies substantially, depending on how impairment is defined.

Neurocognitive speed associates with frontotemporal lobar degeneration TDP-43 subtypes

Frontotemporal lobar degeneration (FTLD) is pathologically heterogeneous with the TAR DNA binding protein 43 kDa (TDP-43) proteinopathy the most common substrate. Previous work has identified atrophy patterns across TDP-43 subtypes with Type A showing greater frontotemporal and parietal atrophy, Type C predominantly anterior temporal, and Type B predominantly posterior frontal. Despite neuroanatomical correlates of involvement, neuropsychological findings have been inconsistent. The current study utilized broader neurocognitive domains based on aggregated neuropsychological measures to distinguish between subtypes. We hypothesized that patterns of neurocognitive domain impairments would predict FTLD-TDP subtype. Fifty-one patients, aged 38-87, were identified post mortem with pathologically confirmed FTLD with TDP-43. Participants were classified into subtypes A, B, or C. Patients had completed neuropsychological assessments as part of their clinical evaluation. Six cognitive domains were created: Language; Cognitive Speed; Memory; Learning; Visuoperception; and Fluency. Binary logistic regression was conducted. All but three patients could be classified as FTLD-TDP Types A, B, or C: 26 as Type A; nine as Type B; and 13 as Type C. Cognitive Speed scores were associated with Types A and C (p < 0.001 and p = 0.003, respectively). Impaired performances on the Trail Making Test differentiated Types A and C. Worse Boston Naming Test and Logical Memory (Immediate) (p < 0.05) scores also increased the likelihood of Type C phenotype. Findings suggest Cognitive Speed associates with TDP-43 subtypes. Type C also demonstrated language-specific involvement. Differences between TDP-43 subtypes further supports the notion of differences in pathophysiology or topography across these types.

Blood pressure and cognition among older adults: a meta-analysis

Hypertension has adverse effects on cognition, can alter cerebral vasculature integrity, and is associated with the pathogenesis of dementia. Using meta-analysis, we correlated blood pressure to multiple cognitive domains among older adults free of clinical stroke and dementia. We identified 230 studies indexed in PubMed and PsycINFO relating blood pressure and cognition. After applying exclusion criteria, we selected n = 12 articles with n = 4,076 participants (age range 43-91 years). Meta-analysis yielded an association between blood pressure and episodic memory (r = -.18, p < .001) and between blood pressure and global cognition (r = -.07, p < .001). When limiting analyses to studies adjusting for vascular covariates (n = 8, n = 2,141), blood pressure was modestly related to global cognition (r = -.11, p < .001), attention (r = .14, p = .002), and episodic memory (r = -.20, p < .001) with a trend for language (r = -.22, p = .07). Findings underscore the need to manage blood pressure as a key prevention method in minimizing abnormal cognitive aging prior to the onset of clinical dementia.

Neuropsychological assessment of driving safety risk in older adults with and without neurologic disease

Decline in cognitive abilities can be an important contributor to the driving problems encountered by older adults, and neuropsychological assessment may provide a practical approach to evaluating this aspect of driving safety risk. The purpose of the present study was to evaluate several commonly used neuropsychological tests in the assessment of driving safety risk in older adults with and without neurological disease. A further goal of this study was to identify brief combinations of neuropsychological tests that sample performances in key functional domains and thus could be used to efficiently assess driving safety risk. A total of 345 legally licensed and active drivers over the age of 50, with no neurologic disease (N = 185), probable Alzheimer's disease (N = 40), Parkinson's disease (N = 91), or stroke (N = 29), completed vision testing, a battery of 10 neuropsychological tests, and an 18-mile drive on urban and rural roads in an instrumented vehicle. Performances on all neuropsychological tests were significantly correlated with driving safety errors. Confirmatory factor analysis was used to identify 3 key cognitive domains assessed by the tests (speed of processing, visuospatial abilities, and memory), and several brief batteries consisting of one test from each domain showed moderate corrected correlations with driving performance. These findings are consistent with the notion that driving places demands on multiple cognitive abilities that can be affected by aging and age-related neurological disease, and that neuropsychological assessment may provide a practical off-road window into the functional status of these cognitive systems.

Discrete neuroanatomical networks are associated with specific cognitive abilities in old age

There have been many attempts at explaining age-related cognitive decline on the basis of regional brain changes, with the usual but inconsistent findings being that smaller gray matter volumes in certain brain regions predict worse cognitive performance in specific domains. Additionally, compromised white matter integrity, as suggested by white matter hyperintensities or decreased regional white matter fractional anisotropy, has an adverse impact on cognitive functions. The human brain is, however, a network and it may be more appropriate to relate cognitive functions to properties of the network rather than specific brain regions. We report on graph theory-based analyses of diffusion tensor imaging tract-derived connectivity in a sample of 342 healthy individuals aged 72-92 years. The cognitive domains included processing speed, memory, language, visuospatial, and executive functions. We examined the association of these cognitive assessments with both the connectivity of the whole brain network and individual cortical regions. We found that the efficiency of the whole brain network of cortical fiber connections had an influence on processing speed and visuospatial and executive functions. Correlations between connectivity of specific regions and cognitive assessments were also observed, e.g., stronger connectivity in regions such as superior frontal gyrus and posterior cingulate cortex were associated with better executive function. Similar to the relationship between regional connectivity efficiency and age, greater processing speed was significantly correlated with better connectivity of nearly all the cortical regions. For the first time, regional anatomical connectivity maps related to processing speed and visuospatial and executive functions in the elderly are identified.