Subtle changes in daily functioning predict conversion from normal to mild cognitive impairment or dementia: an analysis of the NACC database

Does Mild Functional Impairment Predict Dementia in Older Adults With Normal Cognition?

OBJECTIVES

Functional impairment can be an early indicator of cognitive decline. However, its predictive utility in cognitively normal (CN) older adults remains unclear. This study aimed to determine whether mild functional impairment (MFI) in CN older adults could predict incident dementia over 6 years, in addition to assessing its association with cognitive performance.

DESIGN

A longitudinal study with a 6-year follow-up.

PARTICIPANTS

A cohort of 296 community-dwelling CN older adults.

MEASUREMENTS

MFI was defined by cutoffs for impairment on an objective performance-based and/or subjective questionnaire-based functional assessment. Cox regression analysis was conducted to assess the relationship between MFI and risk of incident dementia and cognitive performances over 6 years. Linear regression analysis examined the association between MFI and baseline cognitive performance.

RESULTS

There were no significant longitudinal associations between MFI and incident dementia or changes in cognitive performance over 6 years. Defining MFI using both performance-based and informant-reported assessments was predictive of dementia. Cross-sectional analyses demonstrated significant associations between MFI and poorer baseline global cognition and performance in attention, visuospatial ability, and executive functioning.

CONCLUSIONS

CN older adults with MFI were not at an increased risk of developing dementia over 6 years. A definition of functional impairment requiring both performance-based and informant-based assessments may be useful in predicting dementia.

A Transformer Approach for Cognitive Impairment Classification and Prediction

INTRODUCTION

Early classification and prediction of Alzheimer disease (AD) and amnestic mild cognitive impairment (aMCI) with noninvasive approaches is a long-standing challenge. This challenge is further exacerbated by the sparsity of data needed for modeling. Deep learning methods offer a novel method to help address these challenging multiclass classification and prediction problems.

METHODS

We analyzed 3 target feature-sets from the National Alzheimer Coordinating Center (NACC) dataset: (1) neuropsychological (cognitive) data; (2) patient health history data; and (3) the combination of both sets. We used a masked Transformer-encoder without further feature selection to classify the samples on cognitive status (no cognitive impairment, aMCI, AD)-dynamically ignoring unavailable features. We then fine-tuned the model to predict the participants' future diagnosis in 1 to 3 years. We analyzed the sensitivity of the model to input features via Feature Permutation Importance.

RESULTS

We demonstrated (1) the masked Transformer-encoder was able to perform prediction with sparse input data; (2) high multiclass current cognitive status classification accuracy (87% control, 79% aMCI, 89% AD); (3) acceptable results for 1- to 3-year multiclass future cognitive status prediction (83% control, 77% aMCI, 91% AD).

CONCLUSION

The flexibility of our methods in handling inconsistent data provides a new venue for the analysis of cognitive status data.

Analysis of the relationship between blood pressure variability and subtle cognitive decline in older adults

BACKGROUND

Blood pressure variability (BPV) has been shown to be related to mild cognitive impairment and Alzheimer's disease in a number of studies. However, the relationship between BPV and subtle cognitive decline (SCD) has received minimal attention in this field of research to date and has rarely been reported.

AIM

To examine whether SCD is independently associated with changes in BPV in older adults.

METHODS

Participants were selected based on having participated in cognitive function evaluation and ambulatory blood pressure measurement at the Shanghai Sixth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine between June 2020 and August 2022. The participants included 182 individuals with SCD as the experimental group and 237 with normal cognitive function as the control group. The basic data, laboratory examinations, scale tests, and ambulatory blood pressure test results of the two groups were analyzed retrospectively, and the relationship between SCD and BPV was subsequently evaluated.

RESULTS

Significant differences were observed between the two groups of participants (P < 0.05) in terms of age, education level, prevalence rate of diabetes, fasting blood glucose level, 24-h systolic blood pressure standard deviation and coefficient of variation, 24-h diastolic blood pressure standard deviation and coefficient of variation. The scale monitoring results showed significant differences in the scores for memory, attention, and visual space between the experimental and control groups. Logistic regression analysis indicated that age, education level, blood sugar level, and BPV were factors influencing cognitive decline. Linear regression analysis showed that there was an independent correlation between blood pressure variation and SCD, even after adjusting for related factors. Each of the above differences was still significant.

CONCLUSION

This study suggests that increased BPV is associated with SCD.

Are Protective Activities and Limitations in Practical Skills of Daily Living Associated with the Cognitive Performance of People with Mild Cognitive Impairment? Baseline Results from the BrainFit-Nutrition Study

Limitations in daily living have not yet been described adequately for mild cognitive impairment (MCI). In this study, we investigated first, time spent on protective activities (social, mental, and physical) and second, limitations in practical skills of daily living, both for people with MCI. We used baseline data from 270 individuals who participated in the randomized controlled trial BrainFit-Nutrition. The Montreal Cognitive Assessment (MoCA) was used to identify people with MCI. Participants were asked how much time they spent engaged in social, mental, and physical activities each week. Furthermore, the Bayer-ADL scale was used to quantify deficits in activities of daily living (ADLs). Regarding protection, the number of hours spent engaged in the three activity areas was significantly correlated with the cognitive performance in people with MCI. Social activities were positively associated with current cognitive performance. Concerning the limitations in practical skills of daily living, older and more cognitively impaired individuals were affected. Memory and orientation appear to be among the first practical skills of daily living that become impaired in people with MCI. Treatment recommendations for people with MCI include an increase in social, mental, and physical activities as well as the promotion of a healthy lifestyle.

Identifying subtle functional change in individuals with mild cognitive impairment: development and validation of the Healthy Brain Ageing - Functional Assessment Questionnaire

Accumulating research suggests that individuals with Mild Cognitive Impairment (MCI) experience subtle functional changes, but that available functional assessment tools are insensitive to this. To address this gap, we describe the development and validation of the self-report, "Healthy Brain Ageing Functional Assessment Questionnaire" (HBA-FAQ). We examined the factor structure and psychometric properties of the HBA-FAQ in 503 participants with normal cognition, subjective cognitive decline (SCD), MCI or dementia. Our results found the HBA-FAQ to have good reliability, validity and stronger discriminative ability between healthy control participants and those with SCD (0.734, p = .001), MCI (0.666, p = .012) and dementia (0.798, p < .001) compared to a widely-used instrumental activities of daily living screener. In conclusion, the HBA-FAQ is a valid, reliable self-report tool, providing an efficient and sensitive approach to identifying subtle changes in daily functioning in older people at risk of dementia.

Longitudinal Predictors of Informant-Rated Everyday Function in Mild Cognitive Impairment

OBJECTIVE

To examine predictors of informant-reported everyday functioning in mild cognitive impairment (MCI) and relations between everyday function and conversion to dementia.

METHODS

Informants of participants (n = 2614) with mild cognitive impairment (MCI) were administered the Functional Activities Questionnaire (FAQ). Changes in dimensions of functional ability as determined by an exploratory factor analysis (EFA) were examined over 3 years and participant predictors of change were examined using multilevel modeling (MLM).

RESULTS

The FAQ consisted of 3 factors, multistep, finance, and memory/orientation daily tasks. Impairment in memory/orientation tasks was significantly higher than impairment in multistep tasks. Worse functioning was associated with greater depression, worse memory, worse speed/EF, higher years of education and identifying as White. There was variability in some of these associations with different FAQ factors. Impairments in financial and memory/orientation daily tasks predicted follow-up conversion to dementia.

CONCLUSIONS

Depression, speed/EF, and memory are consistently associated with domains of everyday functioning. Race, education, and age may be more variability associated with everyday functioning. Specific attention should be paid to subtle declines in the financial and memory/orientation domains as they may uniquely predict future dementia development. Depression may be a modifiable risk factor associated with functional impairment over time.

The ecological validity of the Uniform Data Set 3.0 neuropsychological battery in individuals with mild cognitive impairment and dementia

Objective: Ecological validity refers to the ability of neuropsychological measures to predict real world performance. Questions remain as to the ecological validity of commonly used measures, particularly regarding their relationships to global versus specific activities of daily living among those with neurodegenerative disease. We explored these issues through the lens of the Uniform Data Set 3.0 Neuropsychological battery (UDS3NB) in individuals with mild cognitive impairment and dementia. Method: UDS3NB and informant rated Functional Activities Questionnaire scales were evaluated from 2,253 individuals with mild cognitive impairment and dementia. Ordinal regression equations were used to explore the relationships of demographic and cognitive variables with overall and specific instrumental activities of daily living. Results: Delayed recall for visual and verbal material, and performance on trail making tests were consistent predictors of global and specific functions. Specific skills (i.e. naming or figure copy) showed differential relationships with specific activities, while phonemic fluency was not related to any particular activity. Conclusions: Measures in the UDS3NB predicted activities of daily living in individuals with MCI and dementia, providing initial support for the ecological validity of these tests. Specifically, measures that tap core deficits of Alzheimer's disease, such as delayed recall and sequencing/shifting, are consistent predictors of performance in daily tasks.

Altered Angular Gyrus Resting State Functional Connectivity Associated with Financial Capacity in Mild Cognitive Impairment

BACKGROUND

Financial capacity (FC) is a complex ability commonly impaired in older individuals with cognitive impairment; however, the underlying neural mechanisms are not well understood.

OBJECTIVE

To assess resting state functional connectivity using functional magnetic resonance imaging (rs-fMRI) in individuals with mild cognitive impairment (MCI) and impaired FC compared to cognitively normal older adults.

METHODS

rs-fMRI scans were obtained from individuals with MCI (N = 17) and normal older adults (N = 15). All participants completed the Financial Capacity Instrument Short Form (FCI-SF) and neuropsychological assessments. Based on previous findings, the left angular gyrus (lAG) was used as the seed region. Connectivity correlation coefficients were calculated for each seed-based connection that showed significantly altered connectivity. A Pearson's correlation was calculated between the connectivity correlation values from relevant regions and FC and other cognitive measures.

RESULTS

A total of 26 brain regions showed significantly increased functional connectivity with the lAG. Of these regions, 14 were identified as relevant to higher-level cognitive function for analysis. Pearson's correlations showed a significant negative correlation between the FCI-SF total score and increased connectivity between the IAG and the right temporal fusiform cortex (rTFC) (r = -0.455, p = 0.009).

CONCLUSION

Results showed a significant correlation between FC and increased functional connectivity between the lAG and the rTFC in cognitively normal older adults compared to participants with MCI. These exploratory findings suggest that cognitive functions play important roles in FC as the functional connectivity between the lAG and rTFC was not associated with other tests of executive or visuospatial cognition.

Similarities between Cognitive Models of Language Production and Everyday Functioning: Implications for Development of Interventions for Functional Difficulties

The loss of the ability to independently complete activities of daily living, such as meal preparation and household chores, is a defining characteristic of clinical dementia; however, minor difficulties in completing everyday activities emerge in the mild cognitive impairment stage, and even healthy older adults exhibit subtle functional difficulties compared to younger adults. These functional difficulties are associated with an array of negative outcomes, including decreased quality of life, higher costs of care, and increased frustration, depression, caregiver burden, and institutionalization. While cognitive models have been proposed to explain the functional deficits seen in dementia and subtler forms of cognitive decline, in contrast to other cognitive disorders such as aphasia, there are essentially no theoretically motivated interventions to address difficulties in everyday functioning. Proposed models of functional impairment share features with cognitive processing models of language, including hierarchical organization of representations and interactive, spreading activation; thus, an examination of aphasia interventions has the potential to inform the development of theoretically motivated interventions for everyday activities. This review first addresses the shared characteristics of cognitive models of everyday function and language, with a focus on linguistic production. Next, we will present aphasia interventions that target single-word production, sentence production, short-term memory, and semantics, and discuss their implications for everyday functioning interventions. We conclude with a discussion of limitations of the language-everyday functioning comparison as well as areas of future research.

NIA-AA Alzheimer's Disease Framework: Clinical Characterization of Stages

BACKGROUND

To operationalize the National Institute on Aging - Alzheimer's Association (NIA-AA) Research Framework for Alzheimer's Disease 6-stage continuum of clinical progression for persons with abnormal amyloid.

METHODS

The Mayo Clinic Study of Aging is a population-based longitudinal study of aging and cognitive impairment in Olmsted County, Minnesota. We evaluated persons without dementia having 3 consecutive clinical visits. Measures for cross-sectional categories included objective cognitive impairment (OBJ) and function (FXN). Measures for change included subjective cognitive impairment (SCD), objective cognitive change (ΔOBJ), and new onset of neurobehavioral symptoms (ΔNBS). We calculated frequencies of the stages using different cutoff points and assessed stability of the stages over 15 months.

RESULTS

Among 243 abnormal amyloid participants, the frequencies of the stages varied with age: 66 to 90% were classified as stage 1 at age 50 but at age 80, 24 to 36% were stage 1, 32 to 47% were stage 2, 18 to 27% were stage 3, 1 to 3% were stage 4 to 6, and 3 to 9% were indeterminate. Most stage 2 participants were classified as stage 2 because of abnormal ΔOBJ only (44-59%), whereas 11 to 21% had SCD only, and 9 to 13% had ΔNBS only. Short-term stability varied by stage and OBJ cutoff points but the most notable changes were seen in stage 2 with 38 to 63% remaining stable, 4 to 13% worsening, and 24 to 41% improving (moving to stage 1).

INTERPRETATION

The frequency of the stages varied by age and the precise membership fluctuated by the parameters used to define the stages. The staging framework may require revisions before it can be adopted for clinical trials. ANN NEUROL 2021;89:1145-1156.

Impaired Financial Decision-Making as an Early Indicator of Cognitive Decline: A Commentary

Cognitive impairment and dementia are public health concerns with significant financial implications for both individual households and public insurance systems. Though research has refined diagnostic tools for cognitive impairment and dementia diseases, little attention has focused on how cognitive decline may impact financial security. Research indicates that financial decision-making may be one of the first cognitive abilities impacted by cognitive decline, putting individuals at risk of financial fraud and exploitation. However, financial decision-making is not directly assessed in cognitive screenings. Identification of prodromal decline in financial decision-making may help individuals to preserve their financial security and reduce the likelihood of relying on public benefits. This commentary outlines the need for social workers and researchers to better understand the relationship between cognitive health, financial decision-making, and financial security in later life to formulate culturally responsive strategies that can uphold and benefit financial statuses, especially for minoritized communities.

Everyday Function in Alzheimer’s and Parkinson’s Patients with Mild Cognitive Impairment

Background: Instrumental activities of daily living (IADL) impairment can begin in mild cognitive impairment (MCI), and is the core criteria for diagnosing dementia in both Alzheimer’s (AD) and Parkinson’s (PD) diseases. The Functional Activities Questionnaire (FAQ) has high discriminative power for dementia and MCI in older age populations, but is influenced by demographic factors. It is currently unclear whether the FAQ is suitable for assessing cognitive-associated IADL in non-demented PD patients, as motor disorders may affect ratings. Objective: To compare IADL profiles in MCI patients with PD (PD-MCI) and AD (AD-MCI) and to verify the discriminative ability of the FAQ for MCI in patients with (PD-MCI) and without (AD-MCI) additional motor impairment. Methods: Data of 42 patients each of PD-MCI, AD-MCI, PD cognitively normal (PD-CN), and healthy controls (HC), matched according to age, gender, education, and global cognitive impairment were analyzed. ANCOVA and binary regressions were used to examine the relationship between the FAQ scores and groups. FAQ cut-offs for PD-MCI (versus PD-NC) and AD-MCI (versus HC) were separately identified using receiver operating characteristic analyses. Results: FAQ total score did not differentiate between MCI groups. PD-MCI subjects had greater difficulties with tax records and traveling while AD-MCI individuals were more impaired in managing finances and remembering appointments. Classification accuracy of the FAQ was good for diagnosing AD-MCI (69%, cut-off ≥1) compared to HC, and sufficient for differentiating PD-MCI (38.1%, cut-off ≥3) from PD-CN. Conclusion: The FAQ task profiles and classification accuracy differed between MCI related to PD and AD.

Cerebrovascular and Neurodegenerative Pathologies in Long-Term Stable Mild Cognitive Impairment

BACKGROUND

Mild cognitive impairment (MCI) is considered by some to be a prodromal phase of a progressive disease (i.e., neurodegeneration) resulting in dementia; however, a substantial portion of individuals (ranging from 5-30%) remain cognitively stable over the long term (sMCI). The etiology of sMCI is unclear but may be linked to cerebrovascular disease (CVD), as evidence from longitudinal studies suggest a significant proportion of individuals with vasculopathy remain stable over time.

OBJECTIVE

To quantify the presence of neurodegenerative and vascular pathologies in individuals with long-term (>5-year) sMCI, in a preliminary test of the hypothesis that CVD may be a contributor to non-degenerative cognitive impairment. We expect frequent vasculopathy at autopsy in sMCI relative to neurodegenerative disease, and relative to individuals who convert to dementia.

METHODS

In this retrospective study, using data from the National Alzheimer's Coordinating Center, individuals with sMCI (n = 28) were compared to those with MCI who declined over a 5 to 9-year period (dMCI; n = 139) on measures of neurodegenerative pathology (i.e., Aβ plaques, neurofibrillary tangles, TDP-43, and cerebral amyloid angiopathy) and CVD (infarcts, lacunes, microinfarcts, hemorrhages, and microbleeds).

RESULTS

Alzheimer's disease pathology (Aβ plaques, neurofibrillary tangles, and cerebral amyloid angiopathy) was significantly higher in the dMCI group than the sMCI group. Microinfarcts were the only vasculopathy associated with group membership; these were more frequent in sMCI.

CONCLUSION

The most frequent neuropathology in this sample of long-term sMCI was microinfarcts, tentatively suggesting that silent small vessel disease may characterize non-worsening cognitive impairment.

Predementia constructs: Mild cognitive impairment or mild neurocognitive disorder? A narrative review

BACKGROUND

Predementia is a heuristic umbrella concept to classify older adults with cognitive impairment who do not suffer dementia. Many diagnostic entities have been proposed to address this concept, but most of them have not had widespread acceptance.

AIMS

To review clinical definitions, epidemiologic data (prevalence, incidence) and rate of conversion to dementia of the main predementia constructs, with special interest in the two most frequently used: mild cognitive impairment (MCI) and minor neurocognitive disorder (miNCD).

METHODS

We have selected in three databases (MEDLINE, Web of Science and Google scholar) the references from inception to 31 December 2019 of relevant reviews, population and community-based surveys, and clinical series with >500 participants and >3 years follow-up as the best source of evidence.

MAIN RESULTS

The history of predementia constructs shows that MCI is the most referred entity. It is widely recognized as a clinical syndrome harbinger of dementia of several etiologies, mainly MCI due to Alzheimer's disease. The operational definition of MCI has shortcomings: vagueness of its requirement of "preserved independence in functional abilities" and others. The recent miNCD construct presents analogous difficulties. Current data indicate that it is a stricter predementia condition, with lower prevalence than MCI, less sensitivity to cognitive decline and, possibly, higher conversion rate to dementia.

CONCLUSIONS

MCI is a widely employed research and clinical entity. Preliminary data indicate that the clinical use of miNCD instead of MCI requires more scientific evidence. Both approaches have common limitations that need to be addressed.

Regional Hypoperfusion Predicts Decline in Everyday Functioning at Three-Year Follow-Up in Older Adults without Dementia

BACKGROUND

Increasing evidence indicates that cerebrovascular dysfunction may precede cognitive decline in aging and Alzheimer's disease (AD). Reduced cerebral blood flow (CBF) is associated with cognitive impairment in older adults. However, less is known regarding the association between CBF and functional decline, and whether CBF predicts functional decline beyond cerebrovascular and metabolic risk factors.

OBJECTIVE

To examine the association between regional CBF and functional decline in nondemented older adults.

METHOD

One hundred sixty-six (N = 166) participants without dementia from the Alzheimer's Disease Neuroimaging Initiative underwent neuropsychological testing and neuroimaging. Pulsed arterial spin labeling magnetic resonance imaging was acquired to quantify resting CBF. Everyday functioning was measured using the Functional Assessment Questionnaire at baseline and annual follow-up visit across three years.

RESULTS

Adjusting for age, education, sex, cognitive status, depression, white matter hyperintensity volume, cerebral metabolism, and reference (precentral) CBF, linear mixed effects models showed that lower resting CBF at baseline in the medial temporal, inferior temporal, and inferior parietal lobe was significantly associated with accelerated decline in everyday functioning. Results were similar after adjusting for conventional AD biomarkers, including cerebrospinal fluid (CSF) amyloid-β (Aβ) and hyperphosphorylated tau (p-tau) and apolipoprotein E (APOE) ɛ4 positivity. Individuals who later converted to dementia had lower resting CBF in the inferior temporal and parietal regions compared to those who did not.

CONCLUSION

Lower resting CBF in AD vulnerable regions including medial temporal, inferior temporal, and inferior parietal lobes predicted faster rates of decline in everyday functioning. CBF has utility as a biomarker in predicting functional declines in everyday life and conversion to dementia.

Informant Reporting in Mild Cognitive Impairment: Sources of Discrepancy on the Functional Activities Questionnaire

OBJECTIVE

Relative to dementia, little is known about informant bias in mild cognitive impairment (MCI). We investigated the influence of informant demographic and relational characteristics on reports of everyday functioning using the Functional Activities Questionnaire (FAQ).

METHOD

Four thousand two hundred eighty-four MCI participants and their informants from the National Alzheimer's Coordinating Center Uniform Data Set were included. Informants were stratified according to cohabitation, relationship, visit frequency, race/ethnicity, education, and sex. Informant-rated Mean FAQ score was compared across these groups using univariate general linear model analyses and post hoc tests. Interactions were tested between informant variables. The predictive contribution of informant variables to FAQ score was explored using hierarchical linear regression. Analyses covaried for participant cognition using a cognitive composite score, and for participant age, sex, and depression.

RESULTS

After controlling for participant cognition, depression, age, and sex, informant-rated FAQ scores varied significantly across all informant variables (p's < .005, ηp2's ≤ .033) except sex and visit frequency. FAQ scores were higher (more impaired) among informants who cohabitate with the participant, among paid caregivers, spouses, and adult children, and among informants with higher levels of education. Scores were lowest (less impaired) among Black/African American informants as compared to all other racial/ethnic groups.

CONCLUSIONS

Demographic and relational characteristics of informants influence the perception and reporting of instrumental activities of daily living in adults with MCI. As everyday functioning is crucial for differential diagnosis and treatment outcome measurement, it is important to be aware of sources of informant report discrepancies.

Synthetic review of financial capacity in cognitive disorders: Foundations, interventions, and innovations

Purpose of review

Financial capacity (FC) is a complex, multi-dimensional construct that changes over the lifespan and commonly becomes impaired as individuals age and develop dementia. Impaired FC results in several important negative outcomes including loss of independence and increased victimization and abuse. The goal of this review is to synthesize current knowledge of the assessment and intervention of impaired financial capacity in order to propose its further development in the context of technological advancements.

Recent Findings

Current methods of assessing FC are based on conceptual foundations that include judgment, procedural, and other pragmatic skills. The neurocognitive correlates of FC include basic arithmetic skills, attention, and visual memory. These cognitive domains are presently assessed through clinical and neuropsychological evaluation as well as instruments specifically designed to assess financial capacity. Despite having a firm conceptual and neurocognitive foundation, current assessment methods of FC are limited by their ability to be flexible, individualizable, or scalable.

Summary

Computer and software technologies such as artificial intelligence, virtual reality, and the internet of things are exciting tools to achieve the ultimate goal of developing measures that allow patients to maintain or support maximal independence in financial functioning. These tools will allow for contemporaneous and ecologically valid assessment and would be useful to legal professionals and clinicians in determinations of financial competency and capacity. Moreover, interventions that provide safety and monitoring while allowing patients maximal autonomy of preserved financial abilities are needed.

Pattern of regional white matter hyperintensity volume in mild cognitive impairment subtypes and associations with decline in daily functioning

White matter hyperintensities (WMHs), a marker of small-vessel cerebrovascular disease, increase risk for mild cognitive impairment (MCI). Less is known about whether regional WMHs distinguish MCI subtypes and predict decline in everyday functioning. About 618 Alzheimer's Disease Neuroimaging Initiative participants (301 cognitively normal [CN]; 232 amnestic MCI [aMCI]; 85 nonamnestic MCI [naMCI]) underwent neuropsychological testing, MRI, and assessment of everyday functioning. aMCI participants showed greater temporal (p = 0.002) and occipital WMHs (p = 0.030) relative to CN whereas naMCI participants had greater frontal (p = 0.045), temporal (p = 0.003), parietal (p = 0.018), and occipital (p < 0.001) WMH compared with CN. Relative to those with aMCI, individuals with naMCI showed greater occipital WMH (p = 0.013). Greater WMH in temporal (p = 0.001) and occipital regions (p = 0.006) was associated with faster decline in everyday functioning across the sample. Temporal lobe WMHs were disproportionately associated with accelerated functional decline among naMCI (p = 0.045). Regional WMH volumes vary across cognitive groups and predict functional decline. Cerebrovascular markers may help identify individuals at risk for decline and distinguish subtypes of cognitive impairment.

Differential Effect of APOE ɛ4 Status and Elevated Pulse Pressure on Functional Decline in Cognitively Normal Older Adults

BACKGROUND/OBJECTIVE

The APOE ɛ4 allele and increased vascular risk have both been independently linked to cognitive impairment and dementia. Since few studies have characterized how these risk factors affect everyday functioning, we investigated the relationship between APOE ɛ4 genotype and elevated pulse pressure (PP) on functional change in cognitively normal participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI).

METHODS

738 normally aging participants underwent APOE genotyping, and baseline PP was calculated from blood pressure indices. The Functional Activities Questionnaire (FAQ) was completed by participants' informant at baseline and 6, 12, 24, 36, and 48-month follow-up visits. Multiple linear regression and multilevel modeling were used to examine the effects of PP and APOE ɛ4 genotype on cross-sectional and longitudinal FAQ scores, respectively.

RESULTS

Adjusting for demographic and clinical covariates, results showed that both APOE ɛ4 status and elevated PP predicted greater functional difficulty trajectories across four years of follow-up. Interestingly, however, elevated PP was associated with greater functional decline over time in ɛ4 non-carriers versus carriers.

CONCLUSION

Results show that, although APOE ɛ4 status is the prominent predictor of functional difficulty for ɛ4 carriers, an effect of arterial stiffening on functional difficulty was observed in non-carriers. Future studies are needed in order to clarify the etiology of the association between PP and different brain aging processes, and further explore its utility as a marker of dementia risk. The present study underscores the importance of targeting modifiable risk factors such as elevated PP to prevent or slow functional decline and pathological brain aging.

Cognitive dispersion is a sensitive marker for early neurodegenerative changes and functional decline in nondemented older adults

OBJECTIVE

Intraindividual cognitive variability (IIV), a measure of within-person variability across cognitive measures at a single time point, is associated with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Little is known regarding brain changes underlying IIV, or the relationship between IIV and functional ability. Therefore, we investigated the association between IIV and cerebral atrophy in AD-vulnerable regions and everyday functioning in nondemented older adults.

METHOD

736 Alzheimer's Disease Neuroimaging Initiative (ADNI) participants (285 cognitively normal [CN]; 451 MCI) underwent neuropsychological testing and serial MRI over 2 years. Linear mixed effects models examined the association between baseline IIV and change in entorhinal cortex thickness, hippocampal volume, and everyday functioning.

RESULTS

Adjusting for age, sex, apolipoprotein E genotype, amyloid-β positivity, and mean level of cognitive performance, higher baseline IIV predicted faster rates of entorhinal and hippocampal atrophy, as well as functional decline. Higher IIV was associated with both entorhinal and hippocampal atrophy among MCI participants but selective vulnerability of the entorhinal cortex among CN individuals.

CONCLUSIONS

IIV was associated with more widespread medial temporal lobe (MTL) atrophy in individuals with MCI relative to CN, suggesting that IIV may be tracking advancing MTL pathologic changes across the continuum of aging, MCI, and dementia. Findings suggest that cognitive dispersion may be a sensitive marker of neurodegeneration and functional decline in nondemented older adults. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Mind the gaps: What we don't know about cognitive impairment in essential tremor

INTRODUCTION

Although the hallmark feature of essential tremor (ET) is tremor, there is growing appreciation that cognitive impairment also occurs, including increased prevalence of mild cognitive impairment (MCI) and increased prevalence and incidence of dementia. With emerging knowledge of ET-cognitive impairment, come fundamental questions regarding its course, bases, predictors and clinical outcomes. Studies in the general population and in Parkinson's disease (PD), a related movement disorder, offer a starting point from which to begin filling these clinically important knowledge gaps.

METHODS

A PubMed search (June 2018) identified articles for this review.

RESULTS

Much of our knowledge of cognitive impairment in ET is of the static condition (e.g., prevalence of cognitive impairment in ET), with nearly no information on its bases, predictors and dynamics (i.e., course, and clinical outcomes). In PD, where such data have been published, rates of cognitive decline and conversion to MCI/dementia are higher than in the general population. Predictors of cognitive change in PD and the general population have also been identified, yet they only partially overlap one another.

CONCLUSION

The predictors and dynamics of cognitive impairment have been investigated fairly extensively in the general population, to a somewhat lesser extent in PD, and are emerging only now in ET. We suggest that longitudinal studies specific to ET are needed, and we outline variables to be considered in these investigations. Increased knowledge of ET-cognitive impairment will facilitate meaningful counseling of patients and their families.

Heterogeneity of Informant-Reported Functional Performance in Mild Cognitive Impairment: A Latent Profile Analysis of the Functional Activities Questionnaire

Heterogeneity of subtle functional difficulties in mild cognitive impairment (MCI) remains poorly understood. We characterized patterns of informant reports of functional abilities among participants with MCI and the relation between functional ability pattern and cognitive abilities and subsequent decline. Data from 4,273 MCI participants from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS) were included in latent profile analyses (LPA) of informant responses on the Functional Activities Questionnaire (FAQ). Profiles from the best fitting model were compared on demographic, clinical, and cognitive variables. The best fitting model supported three profiles varying by level and type of difficulty: intact function (n = 3,299), intermediate (n = 769), and high ratings of difficulty (n = 205). For the Intermediate profile, items related to finances, remembering dates, and travel were rated as most difficult. The High Ratings profile also had elevated ratings on the meal preparation item. Participants with either the Intermediate or High Ratings profile demonstrated a three-fold increase in conversion to dementia as compared to participants with the Intact profile. Demographically, the Intact profile was younger and consisted of a higher proportion of minorities. On cognitive tests, the Intact profile showed the best performance, and the Intermediate profile performed comparably to or better than the High Ratings profile. There is meaningful heterogeneity in informant ratings of function in MCI, though individuals with MCI whose informants report even intermediate-level functional difficulties are more likely to progress to dementia, suggesting that even subtle functional difficulties place individuals at higher risk for future decline.

Pre-Mild Cognitive Impairment: Can Visual Memory Predict Who Rapidly Convert to Mild Cognitive Impairment?

OBJECTIVE

Little is known about the natural course of pre-mild cognitive impairment (pre-MCI) and predictors to MCI. We followedup individuals with pre-MCI and cognitively normal (CN) elders to identify neuropsychological predictors for rapid conversion to MCI.

METHODS

Seventy-seven individuals with pre-MCI and 180 CN elders were recruited from the pool of individuals registered at the National Research Center for Dementia in Gwangju, Korea. We followed-up with them after a mean of 14±2.29 months. All participants underwent comprehensive clinical and neuropsychological assessment. Logistic regression analysis examined the ability of neuropsychological tests to predict conversions to MCI.

RESULTS

Of 257 participants, 142 (55.3%) were eligible for the follow-up study (102 CN, 40 pre-MCI). Logistic regression revealed that spatial delayed recall significantly predicted the conversion from pre-MCI to MCI. In CN, copy for a complex figure significantly predicted the conversion to pre-MCI or MCI.

CONCLUSION

Our findings indicated that spatial delayed recall was associated with rapid conversion from pre-MCI to MCI. Spatial organization and planning, measured by complex figure reproduction, were associated with rapid conversion from CN to pre-MCI or MCI. Our study suggests that inclusion of visuospatial reproduction and memory using a complex figure further facilitates early detection of MCI.

Word-list intrusion errors predict progression to mild cognitive impairment

OBJECTIVE

Preclinical Alzheimer's disease (AD) defined by a positive AD biomarker in the presence of normal cognition is presumed to precede mild cognitive impairment (MCI). Subtle cognitive deficits and cognitive inefficiencies in preclinical AD may be detected through process and error scores on neuropsychological tests in those at risk for progression to MCI.

METHOD

Cognitively normal participants (n = 525) from the Alzheimer's Disease Neuroimaging Initiative were followed for up to 5 years and classified as either stable normal (n = 305) or progressed to MCI (n = 220). Cox regressions were used to determine whether baseline process scores on the Rey Auditory Verbal Learning Test (AVLT; intrusion errors, learning slope, proactive interference, retroactive interference) predicted progression to MCI and a Clinical Dementia Rating (CDR) score of 1 after considering demographic characteristics, apolipoprotein E ε4 status, cerebrospinal fluid AD biomarkers, ischemia risk, mood, functional difficulty, and standard neuropsychological total test scores for the model.

RESULTS

Baseline AVLT intrusion errors predicted progression to MCI (hazard ratio = 1.04, 95% confidence interval 1.01-1.07, p = .008) and improved model fit after the other valuable predictors were already in the model, χ2(df = 1) = 6.330, p = .012. AVLT intrusion errors also predicted progression to CDR = 1 (hazard ratio = 1.10, 95% confidence interval 1.02-1.18, p = .016) and again improved model fit, χ2(df = 1) = 4.682, p = .030.

CONCLUSIONS

Intrusion errors on the AVLT contribute unique value for predicting progression from normal cognition to MCI and normal cognition to mild dementia (CDR = 1). Intrusion errors appear to reflect subtle change and inefficiencies in cognition that precede impairment detected by neuropsychological total scores. (PsycINFO Database Record

Longitudinal Study-Based Dementia Prediction for Public Health

The issue of public health in Korea has attracted significant attention given the aging of the country's population, which has created many types of social problems. The approach proposed in this article aims to address dementia, one of the most significant symptoms of aging and a public health care issue in Korea. The Korean National Health Insurance Service Senior Cohort Database contains personal medical data of every citizen in Korea. There are many different medical history patterns between individuals with dementia and normal controls. The approach used in this study involved examination of personal medical history features from personal disease history, sociodemographic data, and personal health examinations to develop a prediction model. The prediction model used a support-vector machine learning technique to perform a 10-fold cross-validation analysis. The experimental results demonstrated promising performance (80.9% F-measure). The proposed approach supported the significant influence of personal medical history features during an optimal observation period. It is anticipated that a biomedical "big data"-based disease prediction model may assist the diagnosis of any disease more correctly.