Estimating the validity of the clinical Dementia Rating Scale: the CERAD experience. Consortium to Establish a Registry for Alzheimer's Disease

Development and Validity of Norms for Cognitive Dispersion on the Uniform Data Set 3.0 Neuropsychological Battery

OBJECTIVE

Cognitive dispersion indexes intraindividual variability in performance across a battery of neuropsychological tests. Measures of dispersion show promise as markers of cognitive dyscontrol and everyday functioning difficulties; however, they have limited practical applicability due to a lack of normative data. This study aimed to develop and evaluate normed scores for cognitive dispersion among older adults.

METHOD

We analyzed data from 4,283 cognitively normal participants aged ≥50 years from the Uniform Data Set (UDS) 3.0. We describe methods for calculating intraindividual standard deviation (ISD) and coefficient of variation (CoV), as well as associated unadjusted scaled scores and demographically adjusted z-scores. We also examined the ability of ISD and CoV scores to differentiate between cognitively normal individuals (n = 4,283) and those with cognitive impairment due to Lewy body disease (n = 282).

RESULTS

We generated normative tables to map raw ISD and CoV scores onto a normal distribution of scaled scores. Cognitive dispersion indices were associated with age, education, and race/ethnicity but not sex. Regression equations were used to develop a freely accessible Excel calculator for deriving demographically adjusted normed scores for ISD and CoV. All measures of dispersion demonstrated excellent diagnostic utility when evaluated by the area under the curve produced from receiver operating characteristic curves.

CONCLUSIONS

Results of this study provide evidence for the clinical utility of sample-based and demographically adjusted normative standards for cognitive dispersion on the UDS 3.0. These standards can be used to guide interpretation of intraindividual variability among older adults in clinical and research settings.

Association Between Executive Dysfunction-Related Activities of Daily Living Disability and Clinical Dementia Rating Domain Patterns in Patients With Vascular Dementia and Age-Matched Patients With Alzheimer's Dementia

OBJECTIVE

Although the Clinical Dementia Rating (CDR) scale was originally developed to stage Alzheimer's dementia (AD), it is now used globally for various types of dementia. The aim of this study was to investigate the characteristic pattern of CDR domains and its association with neuropsychological findings and activities of daily living (ADL) in patients with vascular dementia (VaD) and patients with AD.

METHODS

We recruited very mild to mild VaD and AD patients who were age-matched among the first visitors to a dementia clinic. All subjects underwent a standardized clinical interview, physical and neurological examinations, and laboratory tests, including brain magnetic resonance imaging, according to the protocol of the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease assessment battery.

RESULTS

A total of 105 pairs of VaD and AD patients participated in this study. Although the adjusted scores on Korean version of the Mini-Mental State Examination were similar between the two groups, the VaD patients performed better on the Boston Naming Test, Word List Memory, Word List Recall, Word List Recognition, and Constructional Recall Test. However, the scores on global CDR, CDR sum of boxes, and ADL-related CDR domains were higher in VaD patients than in AD patients (p<0.001). The VaD patients also showed poor performances on the Disability Assessment for Dementia Scale, Frontal Assessment Battery, Executive Clock Drawing Task, and Stroop tests.

CONCLUSION

Despite similar general cognitive function and better memory function, patients with VaD tend to be staged as severer dementia on the CDR scale than patients with AD because of more impaired ADL associated with executive dysfunction.

Evaluation of the Electronic Clinical Dementia Rating for Dementia Screening

Importance

The Clinical Dementia Rating (CDR) is a well-validated instrument widely used to detect and stage dementia due to Alzheimer disease. The digital Electronic Clinical Dementia Rating (eCDR) can be remotely self-administered and automatically scored, with potential to facilitate efficient dementia screening and staging.

Objective

To evaluate the association of the eCDR with the CDR and other in-clinic assessments for screening older adults for cognitive impairment.

Design, Setting, and Participants

This multisite, cross-sectional study used baseline data from a longitudinal, observational study from 2020 to 2023, including up to 3 years of follow-up. Participants were enrolled from 3 Alzheimer Disease Research Centers and the Brain Health Registry. Participants (aged ≥55 years, with a study partner, and no acute or unstable major medical conditions) were recruited during in-clinic visits or by automated emails.

Exposures

Participants completed the Uniform Data Set Version 3 (UDS; including the CDR) in supervised clinical research settings, and then completed the eCDR remotely, online and unsupervised, using their own device.

Main Outcomes and Measures

The primary outcomes were eCDR scores (item; categorical box and global; continuous box and global), CDR scores (item; categorical box and global), and UDS assessment scores. Associations were evaluated using linear and logistic regressions.

Results

A total of 3565 participants were contacted, and 288 were enrolled. Among 173 participants with item-level data (mean [SD] age, 70.84 [7.65] years; 76 women [43.9%]), eCDR to CDR concordance was 90% or higher for 33 items (63%) and 70% to 89% for 13 items (25%). Box (domain) level concordance ranged from 80% (memory) to 99% (personal care). The global score concordance rate was 81%. κ statistics were fair to moderate. Among 206 participants with box and global scores (mean [SD] age, 71.34 [7.68] years; 95 women [46.1%]), eCDR continuous global score was associated with CDR global (categorical) score with an area under the receiver operating characteristic curve of 0.79 (95% CI, 0.70-0.87). Correlations between eCDR and in-clinic UDS assessments were similar to those between CDR sum of box scores and the same in-clinic assessments.

Conclusions and Relevance

These findings suggest that the eCDR is valid and has potential use for screening and assessment of older adults for cognitive and functional decline related to Alzheimer disease. Instrument optimization and validation in diverse cohorts in remote settings are crucial for evaluating scalability and eCDR utility in clinical research, trials, and health care settings.

Disrupted excitation-inhibition balance in cognitively normal individuals at risk of Alzheimer's disease

Background

Sex differences impact Alzheimer's disease (AD) neuropathology, but cell-to-network level dysfunctions in the prodromal phase are unclear. Alterations in hippocampal excitation-inhibition balance (EIB) have recently been linked to early AD pathology.

Objective

Examine how AD risk factors (age, APOE-ɛ4, amyloid-β) relate to hippocampal EIB in cognitively normal males and females using connectome-level measures.

Methods

Individuals from the OASIS-3 cohort (age 42-95) were studied (N = 437), with a subset aged 65+ undergoing neuropsychological testing (N = 231).

Results

In absence of AD risk factors (APOE-ɛ4/Aβ+), whole-brain EIB decreases with age more significantly in males than females (p = 0.021, β = -0.007). Regression modeling including APOE-ɛ4 allele carriers (Aβ-) yielded a significant positive AGE-by-APOE interaction in the right hippocampus for females only (p = 0.013, β = 0.014), persisting with inclusion of Aβ+ individuals (p = 0.012, β = 0.014). Partial correlation analyses of neuropsychological testing showed significant associations with EIB in females: positive correlations between right hippocampal EIB with categorical fluency and whole-brain EIB with the trail-making test (p < 0.05).

Conclusion

Sex differences in EIB emerge during normal aging and progresses differently with AD risk. Results suggest APOE-ɛ4 disrupts hippocampal balance more than amyloid in females. Increased excitation correlates positively with neuropsychological performance in the female group, suggesting a duality in terms of potential beneficial effects prior to cognitive impairment. This underscores the translational relevance of APOE-ɛ4 related hyperexcitation in females, potentially informing therapeutic targets or early interventions to mitigate AD progression in this vulnerable population.

The impact of conventional versus robust norming on cognitive characterization and clinical classification of MCI and dementia

We examined the impact of conventional versus robust normative approaches on cognitive characterization and clinical classification of MCI versus dementia. The sample included participants from the National Alzheimer's Coordinating Center Uniform Data Set. Separate demographically adjusted z-scores for cognitive tests were derived from conventional (n = 4273) and robust (n = 602) normative groups. To assess the impact of deriving scores from a conventional versus robust normative group on cognitive characterization, we examined likelihood of having a low score on each neuropsychological test. Next, we created receiver operating characteristic (ROC) curves for the ability of normed scores derived from each normative group to differentiate between MCI (n = 3570) and dementia (n = 1564). We examined the impact of choice of normative group on classification accuracy by comparing sensitivity and specificity values and areas under the curves (AUC). Compared with using a conventional normative group, using a robust normative group resulted in a higher likelihood of low cognitive scores for individuals classified with MCI and dementia. Comparison of the classification accuracy for distinguishing MCI from dementia did not suggest a statistically significant advantage for either normative approach (Z = -0.29, p = .77; AUC = 0.86 for conventional and AUC = 0.86 for robust). In summary, these results indicate that using a robust normative group increases the likelihood of characterizing cognitive performance as low. However, there is not a clear advantage of using a robust over a conventional normative group when differentiating between MCI and dementia.

Statistical harmonization of everyday functioning and dementia-related behavioral measures across nine surveys and trials

Introduction

Efforts to harmonize measures of everyday function and dementia-related behaviors are needed to synthesize across studies in dementia research. There have been some psychometric attempts to harmonize everyday function for secondary analysis, but far less for dementia-related behaviors.

Methods

Statistical co-calibration was performed to generate factor scores representing everyday function and dementia-related behaviors for participants with dementia. We evaluated convergent criterion validity of factor scores and mapped the scores onto established clinical instruments.

Results

Factor analyses of included items fit well to available data. Harmonized factors showed expected associations with the Global Clinical Dementia Rating (CDR) score, with greater impairment (higher Global CDR score) corresponding to higher (more severe) levels on factor scores.

Discussion

We used large, well-characterized samples to derive harmonized factors representing everyday functions and dementia-related behaviors. These harmonized factors can be used to tackle questions about dementia phenotypes which require either large samples or unique subpopulations.

Disrupted Excitation-Inhibition Balance in Cognitively Normal Individuals at Risk of Alzheimer's Disease

BACKGROUND

Sex differences impact Alzheimer's disease (AD) neuropathology, but cell-to-network level dysfunctions in the prodromal phase are unclear. Alterations in hippocampal excitation-inhibition balance (EIB) have recently been linked to early AD pathology.

OBJECTIVE

Examine how AD risk factors (age, APOEɛ4, amyloid-β) relate to hippocampal EIB in cognitively normal males and females using connectome-level measures.

METHODS

Individuals from the OASIS-3 cohort (age 42-95) were studied (N = 437), with a subset aged 65+ undergoing neuropsychological testing (N = 231).

RESULTS

In absence of AD risk factors (APOEɛ4/Aβ+), whole-brain EIB decreases with age more significantly in males than females (p = 0.021, β= -0.007). Regression modeling including APOEɛ4 allele carriers (Aβ-) yielded a significant positive AGE-by-APOE interaction in the right hippocampus for females only (p = 0.013, β= 0.014), persisting with inclusion of Aβ+ individuals (p = 0.012, β= 0.014). Partial correlation analyses of neuropsychological testing showed significant associations with EIB in females: positive correlations between right hippocampal EIB with categorical fluency and whole-brain EIB with the Trail Making Test (p < 0.05).

CONCLUSIONS

Sex differences in EIB emerge during normal aging and progresses differently with AD risk. Results suggest APOEɛ4 disrupts hippocampal balance more than amyloid in females. Increased excitation correlates positively with neuropsychological performance in the female group, suggesting a duality in terms of potential beneficial effects prior to cognitive impairment. This underscores the translational relevance of APOEɛ4 related hyperexcitation in females, potentially informing therapeutic targets or early interventions to mitigate AD progression in this vulnerable population.

A case study on the application evaluation of integrative medical service model for the improvement of quality of life for dementia patients and caregivers

BACKGROUND

Since 4 major diseases and geriatric diseases require consistent management, individuals with any of these diseases cannot live alone and need caregivers' assistance. Given these characteristics, an integrative medical service model for 4 major diseases and geriatric diseases was developed in Korea, currently. Dementia, one of the typical geriatric diseases, requires caregivers' assistance from the beginning because of its enormous burden. Thus, it is necessary to provide an integrative medical service that can improve the quality of life (QoL) for both patients and caregivers. Therefore, this study aims to collect various feedback by applying an integrative medical service, which was developed to improve the QoL in patients with dementia and their caregivers, to a single case, and to modify and improve the integrative medical service model based on the results.

METHOD/DESIGN

The integrative medical service program, which was developed to improve the QoL in patients with dementia and their caregivers in Korea, will be used for a patient-caregiver pair. This is an observational study with quantitative and qualitative feedback from various viewpoints. The program will be conducted in 8 sessions (twice a week, within 120 minutes). The patient will receive both Western and Korean medicine, and an integrative service will be provided to improve cognitive rehabilitation and QoL. Feedback collected at each session will be reflected on the program of the subsequent session.

RESULTS

This study will then modify and improve the program with feedback and provide integrative medical services to a patient with dementia and caregiver.

DISCUSSION

Patients with dementia need a program that would help them maintain cognitive function, and caregivers need a program that would improve their QoL by reducing the caregiving burden. This study is unique because the developed program is performed after modification based on feedback from the previous session. Accordingly, the patient and caregiver can check which program is the most satisfactory and helpful in improving their QoL. We expect that this study can modify the integrative medical service model to the optimized patient-based model. This study can also be used as basic data for a clinical pathway development study that applies the modified model to medical institutes.

Dispersion-based cognitive intra-individual variability in dementia with Lewy bodies

OBJECTIVE

Cognitive fluctuations are characteristic of dementia with Lewy bodies (DLB) but challenging to measure. Dispersion-based intra-individual variability (IIV-d) captures neurocognitive performance fluctuations across a test battery and may be sensitive to cognitive fluctuations but has not been studied in DLB.

METHOD

We report on 5,976 participants that completed the uniform data set 3.0 neuropsychological battery (UDS3NB). IIV-d was calculated via the intra-individual standard deviation across 12 primary UDS3NB indicators. Separate models using mean USD3NB score and the Montreal cognitive assessment (MoCA) total score tested the reproducibility of the incremental value of IIV-d over-and-above global cognition. Binary logistic regressions tested whether IIV-d could classify individuals with and without clinician-rated cognitive fluctuations. Multinomial logistic regressions tested whether IIV-d could differentiate participants with DLB, participants with Alzheimer's disease (AD), and participants with healthy cognition (CH), as well as the incremental diagnostic utility of IIV-d over-and-above clinician-rated cognitive fluctuations.

RESULTS

IIV-d exhibited large univariate associations with clinician-rated and non-clinician-informant reported cognitive fluctuations, which persisted when adjusting for MoCA but not the full battery mean. Of diagnostic relevance, greater IIV-d was consistently associated with DLB and AD relative to CH over-and-above global cognition and clinician-rated cognitive fluctuations. Greater IIV-d was less consistently associated with an increased probability of DLB relative to AD when controlling for global cognition.

CONCLUSIONS

IIV-d accurately differentiates DLB from CH over-and-above global cognition and clinician-rated cognitive fluctuations. IIV-d may supplement a thorough clinical interview of cognitive fluctuations and serve as a standardized performance-based indicator of this transdiagnostic phenomenon. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Development and implementation of an electronic Clinical Dementia Rating and Financial Capacity Instrument-Short Form

Introduction

To address the need for remote assessments of cognitive decline and dementia, we developed and administered electronic versions of the Clinical Dementia Rating (CDR®) and the Financial Capacity Instrument-Short Form (FCI-SF) (F-CAP®), called the eCDR and eFCI, respectively.

Methods

The CDR and FCI-SF were adapted for remote, unsupervised, online use based on item response analysis of the standard instruments. Participants completed the eCDR and eFCI first in clinic, and then at home within 2 weeks.

Results

Of the 243 enrolled participants, 179 (73%) cognitively unimpaired (CU), 50 (21%) with mild cognitive impairment (MCI) or dementia, and 14 (6%) with an unknown diagnosis, 84% and 85% of them successfully completed the eCDR and eFCI, respectively, at home.

Discussion

These results show initial feasibility in developing and administering online instruments to remotely assess and monitor cognitive decline along the CU to MCI/very mild dementia continuum. Validation is an important next step.

The Effect of Deep Micro Vibrotactile Stimulation on Cognitive Function of Mild Cognitive Impairment and Mild Dementia

Background: The purpose of this study was to clarify the effect of Deep Micro Vibrotactile (DMV) stimulation on the cognitive functions in elderly people with mild cognitive impairment or mild dementia. Methods: A total of 35 participants with dementia from three nursing homes, who had completed treatment with DMV stimulation at 15−40 Hz (hereinafter, 15−40 Hz DMV stimulation) for a month were recruited for this study. The subjects had received continuous 15−40 Hz DMV stimulation for 24 h a day for 1 month. We assessed the effect of the treatment on the cognitive functions (by the word list memory (WM) test, trail making test-part A (TMT-A) and part B (TMT-B), and symbol digit substitution task (SDST)) and physical functions (grip strength (GS) and usual walking speed (UWS)), by comparing the results at the baseline and after the 1-month intervention (DMV stimulation). Results: The results revealed that the performances in the WM test (p < 0.05), TMT-B (p < 0.05), and SDST (p < 0.01) improved significantly after the intervention. Conclusion: Our findings suggest that 15−40 Hz DMV stimulation is might be effective for improving the cognitive functions in elderly people with dementia. Furthermore, our novel findings showed the different effectiveness of the treatment depending on the stage of cognitive impairments.

Cognitive Intervention Using Information and Communication Technology for Older Adults with Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

Background: Outside activities have decreased due to the spread of the COVID-19 since 2019; therefore, the need for education using information and communication technology (ICT) for older adults with mild cognitive impairment (MCI) has increased. This study systematically evaluated the effects of cognitive enhancement interventions using ICT on older adults with MCI. Methods: Six electronic databases (CINAHL, Cochrane CENTRAL, EMBASE, PubMed, RISS, and KISS) were searched for relevant articles published from 25 January to 10 February, 2021. Results: As a result of the systematic literature review, 12 research papers were finally selected as the literature for quality evaluation, and 11 final papers were selected, excluding one in the quality evaluation. From the synthesis in this study, it was found that cognitive intervention using ICT showed a statistically significant positive effect on cognitive function when compared with various control groups (SMD = 0.4547; p < 0.001; 95% CI: 0.1980–0.7113). Conclusions: Through this study, cognitive intervention using ICT showed a small effect size for older adults with mild cognitive impairment, and statistically significant results were found.

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.

Molecular signature of extracellular matrix pathology in schizophrenia

Growing evidence points to a critical involvement of the extracellular matrix (ECM) in the pathophysiology of schizophrenia (SZ). Decreases of perineuronal nets (PNNs) and altered expression of chondroitin sulphate proteoglycans (CSPGs) in glial cells have been identified in several brain regions. GWAS data have identified several SZ vulnerability variants of genes encoding for ECM molecules. Given the potential relevance of ECM functions to the pathophysiology of this disorder, it is necessary to understand the extent of ECM changes across brain regions, their region- and sex-specificity and which ECM components contribute to these changes. We tested the hypothesis that the expression of genes encoding for ECM molecules may be broadly disrupted in SZ across several cortical and subcortical brain regions and include key ECM components as well as factors such as ECM posttranslational modifications and regulator factors. Gene expression profiling of 14 neocortical brain regions, caudate, putamen and hippocampus from control subjects (n = 14/region) and subjects with SZ (n = 16/region) was conducted using Affymetrix microarray analysis. Analysis across brain regions revealed widespread dysregulation of ECM gene expression in cortical and subcortical brain regions in SZ, impacting several ECM functional key components. SRGN, CD44, ADAMTS1, ADAM10, BCAN, NCAN and SEMA4G showed some of the most robust changes. Region-, sex- and age-specific gene expression patterns and correlation with cognitive scores were also detected. Taken together, these findings contribute to emerging evidence for large-scale ECM dysregulation in SZ and point to molecular pathways involved in PNN decreases, glial cell dysfunction and cognitive impairment in SZ.

How impaired is too impaired? Exploring futile neuropsychological test patterns as a function of dementia severity and cognitive screening scores

Some older adults cannot meaningfully participate in the testing portion of a neuropsychological evaluation due to significant cognitive impairments. There are limited empirical data on this topic. Thus, the current study sought to provide an operational definition for a futile testing profile and examine cognitive severity status and cognitive screening scores as predictors of testing futility at both baseline and first follow-up evaluations. We analysed data from 9,263 older adults from the National Alzheimer's Coordinating Center Uniform Data Set. Futile testing profiles occurred rarely at baseline (7.40%). There was a strong relationship between cognitive severity status and the prevalence of futile testing profiles, χ² (4) = 3559.77, p < .001. Over 90% of individuals with severe dementia were unable to participate meaningfully in testing. Severity range on the Montreal Cognitive Assessment (MoCA) also demonstrated a strong relationship with testing futility, χ² (3) = 3962.35, p < .001. The rate of futile testing profiles was similar at follow-up (7.90%). There was a strong association between baseline dementia severity and likelihood of demonstrating a futile testing profile at follow-up, χ² (4) = 1513.40, p < .001. Over 90% of individuals with severe dementia, who were initially able to participate meaningfully testing, no longer could at follow-up. Similarly, there was a strong relationship between baseline MoCA score band and likelihood of demonstrating a futile testing profile at follow-up, χ² (3) = 1627.37, p < .001. Results can help to guide decisions about optimizing use of limited neuropsychological assessment resources.

An Initial Empirical Operationalization of the Earliest Stages of the Alzheimer's Continuum

PURPOSE

The Alzheimer's Continuum (AC) includes 2 preclinical stages defined by subjective cognitive complaints, transitional cognitive declines, and neurobehavioral symptoms. Operationalization of these stages is necessary for them to be applied in research.

METHODS

Cognitively normal individuals with known amyloid biomarker status were selected from the National Alzheimer's Coordinating Center Uniform Data Set. Participants and their caregivers provided information on subjective cognitive complaints, neurobehavioral features, and objective cognitive functioning.

PATIENTS

The sample included 101 amyloid positive (A+) and 447 amyloid negative (A-) individuals.

RESULTS

Rates of subjective cognitive complaints (A+: 34.90%, A-: 29.90%) and neurobehavioral symptoms (A+: 22.40%, A-: 22.40%) did not significantly differ between A+/- individuals. However, the frequency of transitional cognitive decline was significantly higher among A+ (38.00%) than A- participants (24.90%). We explored various empirical definitions for defining the early stages of the AC among A+ participants. Rates of classification into AC stage 1 versus AC stage 2 varied depending on the number of symptoms required: 57.40% versus 42.60% (1 symptom), 28.70% versus 71.30% (2 symptoms), and 6.90% versus 93.10% (all 3 symptoms).

CONCLUSION

The presence of 2 of the proposed symptom classes to separate AC stage 2 from stage 1 seems to provide a good empirical balance.

Non-benzodiazepine hypnotic use for sleep disturbance in people aged over 55 years living with dementia: a series of cohort studies

BACKGROUND

Sleep disturbance affects around 60% of people living with dementia and can negatively affect their quality of life and that of their carers. Hypnotic Z-drugs (zolpidem, zopiclone and zaleplon) are commonly used to treat insomnia, but their safety and efficacy have not been evaluated for people living with dementia.

OBJECTIVES

To estimate the benefits and harms of Z-drugs in people living with dementia with sleep disturbance.

DESIGN

A series of observational cohort studies using existing data from (1) primary care linked to hospital admission data and (2) clinical cohort studies of people living with dementia.

DATA SOURCES

Primary care study - Clinical Practice Research Datalink linked to Hospital Episode Statistics and Office for National Statistics mortality data. Clinical cohort studies - the Resource Use and Disease Course in Dementia - Nursing Homes (REDIC) study, National Alzheimer's Coordinating Centre (NACC) clinical data set and the Improving Well-being and Health for People with Dementia (WHELD) in nursing homes randomised controlled trial.

SETTING

Primary care study - 371 primary care practices in England. Clinical cohort studies - 47 nursing homes in Norway, 34 Alzheimer's disease centres in the USA and 69 care homes in England.

PARTICIPANTS

Primary care study - NHS England primary care patients diagnosed with dementia and aged > 55 years, with sleep disturbance or prescribed Z-drugs or low-dose tricyclic antidepressants, followed over 2 years. Clinical cohort studies - people living with dementia consenting to participate, followed over 3 years, 12 years and 9 months, for REDIC, NACC and WHELD, respectively.

INTERVENTIONS

The primary exposure was prescription or use of Z-drugs. Secondary exposures included prescription or use of benzodiazepines, low-dose tricyclic antidepressants and antipsychotics.

MAIN OUTCOME MEASURES

Falls, fractures, infection, stroke, venous thromboembolism, mortality, cognitive function and quality of life. There were insufficient data to investigate sleep disturbance.

RESULTS

The primary care study and combined clinical cohort studies included 6809 and 18,659 people living with dementia, with 3089 and 914 taking Z-drugs, respectively. New Z-drug use was associated with a greater risk of fractures (hazard ratio 1.40, 95% confidence interval 1.01 to 1.94), with risk increasing with greater cumulative dose (p = 0.002). The hazard ratio for Z-drug use and hip fracture was 1.59 (95% confidence interval 1.00 to 2.53) and for mortality was 1.34 (95% confidence interval 1.10 to 1.64). No excess risks of falls, infections, stroke or venous thromboembolism were detected. Z-drug use also did not have an impact on cognition, neuropsychiatric symptoms, disability or quality of life.

LIMITATIONS

Primary care study - possible residual confounding because of difficulties in identifying patients with sleep disturbance and by dementia severity. Clinical cohort studies - the small numbers of people living with dementia taking Z-drugs and outcomes not necessarily being measured before Z-drug initiation restricted analyses.

CONCLUSIONS

We observed a dose-dependent increase in fracture risk, but no other harms, with Z-drug use in dementia. However, multiple outcomes were examined, increasing the risk of false-positive findings. The mortality association was unlikely to be causal. Further research is needed to confirm the increased fracture risk. Decisions to prescribe Z-drugs may need to consider the risk of fractures, balanced against the impact of improved sleep for people living with dementia and that of their carers. Our findings suggest that when Z-drugs are prescribed, falls prevention strategies may be needed, and that the prescription should be regularly reviewed.

FUTURE WORK

More research is needed on safe and effective management strategies for sleep disturbance in people living with dementia.

STUDY REGISTRATION

This study is registered as European Union electronic Register of Post-Authorisation Studies (EU PAS) 18006.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 1. See the NIHR Journals Library website for further project information.

Item response theory analysis of the Clinical Dementia Rating

INTRODUCTION

The Clinical Dementia Rating (CDR) is widely used in Alzheimer's disease research studies and has well established reliability and validity. To facilitate the development of an online, electronic CDR (eCDR) for more efficient clinical applications, this study aims to produce a shortened version of the CDR, and to develop the statistical model for automatic scoring.

METHODS

Item response theory (IRT) was used for item evaluation and model development. An automatic scoring algorithm was validated using existing CDR global and domain box scores as the reference standard.

RESULTS

Most CDR items discriminate well at mild and very mild levels of cognitive impairment. The bi-factor IRT model fits best and the shortened CDR still demonstrates very high classification accuracy (81%∼92%).

DISCUSSION

The shortened version of the CDR and the automatic scoring algorithm has established a good foundation for developing an eCDR and will ultimately improve the efficiency of cognitive assessment.

Development and Preliminary Validation of Standardized Regression-Based Change Scores as Measures of Transitional Cognitive Decline

OBJECTIVE

An increasing focus in Alzheimer's disease and aging research is to identify transitional cognitive decline. One means of indexing change over time in serial cognitive evaluations is to calculate standardized regression-based (SRB) change indices. This paper includes the development and preliminary validation of SRB indices for the Uniform Data Set 3.0 Neuropsychological Battery, as well as base rate data to aid in their interpretation.

METHOD

The sample included 1,341 cognitively intact older adults with serial assessments over 0.5-2 years in the National Alzheimer's Coordinating Center Database. SRB change scores were calculated in half of the sample and then validated in the other half of the sample. Base rates of SRB decline were evaluated at z-score cut-points, corresponding to two-tailed p-values of .20 (z = -1.282), .10 (z = -1.645), and .05 (z = -1.96). We examined convergent associations of SRB indices for each cognitive measure with each other as well as concurrent associations of SRB indices with clinical dementia rating sum of box scores (CDR-SB).

RESULTS

SRB equations were able to significantly predict the selected cognitive variables. The base rate of at least one significant SRB decline across the entire battery ranged from 26.70% to 58.10%. SRB indices for cognitive measures demonstrated theoretically expected significant positive associations with each other. Additionally, CDR-SB impairment was associated with an increasing number of significantly declined test scores.

CONCLUSIONS

This paper provides preliminary validation of SRB indices in a large sample, and we present a user-friendly tool for calculating SRB values.

Multivariate neuroanatomical correlates of behavioral and psychological symptoms in dementia and the moderating role of education

Neuropsychiatric symptoms are commonly observed as brain pathology progresses with dementia. Behavioral and affective disturbances underly the distinct neuroanatomical basis of typical symptoms of cognitive impairment; however it remains unclear whether enriched intellectual experience, such as educational attainment, can mitigate the effect of brain structural patterns on neuropsychiatric symptom severity. We utilized the Open Access Series of Imaging Studies (OASIS-3) dataset, which includes brain structural MRI and behavioral symptom evaluation. We included 904 older adults who were mostly cognitively normal, clinically diagnosed with very mild to moderate Alzheimer's disease, or other types of dementia. Canonical correlation analysis was used to identify the patterns of multivariate association between the gray matter structure and neuropsychiatric symptom severity. First, we identified two canonical modes capturing the distinct neuroanatomical basis of common and mood-specific factors of neuropsychiatric symptoms. The first common pattern reflected a smaller volume in the amygdala and adjacent temporal regional thickness. The second mood-specific pattern reflected patterns in lateral and orbital prefrontal regional thickness. In the external correlational analysis, the two canonical correlations reflected global brain volume and white matter lesions; however, the second pattern was not associated with functional impairments or cognitive function. Moreover, older adults with higher education showed an attenuated severity of behavioral symptoms, even with the presence of a brain structural pattern. Our findings suggest that educational attainment, as a proxy of cognitive reserve, can mitigate the severity of behavioral and affective symptoms of dementia.

Nighttime Agitation and Restless Legs Syndrome in Persons With Alzheimer's Disease: Study Protocol for a Double-Blind, Placebo-Controlled, Randomized Trial (NightRest)

Nighttime agitation is a prevalent symptom in persons with Alzheimer's disease (AD). Effective treatments are absent due to our limited knowledge of its etiology. We hypothesized that restless legs syndrome (RLS), a common neurological sensorimotor disorder of uncomfortable leg sensations that appear at night and interfere with sleep, might be a cause for nighttime agitation in persons with AD. RLS is infrequently identified in persons with AD because traditional diagnosis is dependent on patients answering complex questions about their symptoms. With a validated observational tool for RLS diagnosis, the Behavioral Indicators Test-Restless Legs, we aim to diagnose RLS and determine the effect of gabapentin enacarbil (GEn) compared to placebo on nighttime agitation, sleep, antipsychotic medications, and the mechanism for these effects. We hypothesize that frequency of RLS behaviors will mediate the relationship between GEn and nighttime agitation. This study is an 8-week, double-blind, placebo-controlled, randomized pilot clinical trial, followed by an 8-week open-label trial, that is being conducted in long-term care settings and private homes. The results of this study may shift, personalize, and improve standards of care for treatment of nighttime agitation; reduce aggression and other nighttime agitation behaviors; and improve sleep.

TARGETS

Persons with AD with nighttime agitation potentially caused by RLS.

INTERVENTION DESCRIPTION

Diagnose RLS and determine the effect of GEn.

MECHANISMS OF ACTION

The frequency of RLS behaviors will mediate the relationship between GEn and nighttime agitation.

OUTCOMES

Determine the effect of GEn on nighttime agitation, sleep, and antipsychotic medications.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03082755 (Date of registration March 6, 2017). [Research in Gerontological Nursing, 13(6), 280-288.].

Using multivariate base rates of low scores to understand early cognitive declines on the uniform data set 3.0 Neuropsychological Battery

OBJECTIVE

Low neuropsychological test scores are commonly observed even in cognitively healthy older adults. For batteries designed to assess for and track cognitive decline in older adults, documenting the multivariate base rates (MBRs) of low scores is important to differentiate expected from abnormal low score patterns. Additionally, it is important for our understanding of mild cognitive impairment and preclinical declines to and determine how such score patterns predict future clinical states.

METHOD

The current study utilized Uniform Data Set Neuropsychological Battery 3.0 (UDS3NB) data for 5,870 English-speaking, older adult participants from the National Alzheimer's Coordinating Center from 39 Alzheimer's disease Research Centers from March 2015 to December 2018. MBRs of low scores were identified for 2,608 cognitively healthy participants that had completed all cognitive measures. The association of abnormal MBR patterns with subsequent conversion to mild cognitive impairment and dementia were explored.

RESULTS

Depending on the operationalization of "low" score, the MBR of demographically adjusted scores ranged from 1.40 to 79.2%. Posttest probabilities using MBR methods to predict dementia status at 2-year follow up ranged from .06 to .33, while posttest probabilities for conversion to mild cognitive impairment (MCI) ranged from .12-.32.

CONCLUSIONS

The data confirm that abnormal cognitive test scores are common among cognitively normal older adults. Using MBR criteria may improve our understanding of MCI. They may also be used to enrich clinical trial selection processes through recruitment of at-risk individuals. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

The Uniform Dataset 3.0 Neuropsychological Battery: Factor Structure, Invariance Testing, and Demographically Adjusted Factor Score Calculation

OBJECTIVE

The goals of this study were to (1) specify the factor structure of the Uniform Dataset 3.0 neuropsychological battery (UDS3NB) in cognitively unimpaired older adults, (2) establish measurement invariance for this model, and (3) create a normative calculator for factor scores.

METHODS

Data from 2520 cognitively intact older adults were submitted to confirmatory factor analyses and invariance testing across sex, age, and education. Additionally, a subsample of this dataset was used to examine invariance over time using 1-year follow-up data (n = 1061). With the establishment of metric invariance of the UDS3NB measures, factor scores could be extracted uniformly for the entire normative sample. Finally, a calculator was created for deriving demographically adjusted factor scores.

RESULTS

A higher order model of cognition yielded the best fit to the data χ2(47) = 385.18, p < .001, comparative fit index = .962, Tucker-Lewis Index = .947, root mean square error of approximation = .054, and standardized root mean residual = .036. This model included a higher order general cognitive abilities factor, as well as lower order processing speed/executive, visual, attention, language, and memory factors. Age, sex, and education were significantly associated with factor score performance, evidencing a need for demographic correction when interpreting factor scores. A user-friendly Excel calculator was created to accomplish this goal and is available in the online supplementary materials.

CONCLUSIONS

The UDS3NB is best characterized by a higher order factor structure. Factor scores demonstrate at least metric invariance across time and demographic groups. Methods for calculating these factors scores are provided.

Nurse-Led Computerized Cognitive Training for Mild Cognitive Impairment: A Preliminary Study

PURPOSE

This preliminary study aimed to compare the outcomes of an occupational therapist-led and a nurse-led computerized cognitive training (CCT) for mild cognitive impairment (MCI) in older adults.

DESIGN

A single-blind randomized controlled trial was performed.

METHODS

Participants 65 years of age and older with MCI were randomly assigned to a group led by an occupational therapist or by a nurse. Both groups received CCT for 4 weeks.

FINDINGS

Six participants in the occupational therapist-led group and nine in the nurse-led group completed CCT. The nurse-led group showed significant improvement in scores on the Seoul Verbal Learning Test-Elderly's version immediate recall scores (p = .030) and the Korean-Boston Naming Test (p = .012).

CONCLUSIONS

Nurse-led CCT demonstrated improvement in some language and memory areas in older adults with MCI.

CLINICAL RELEVANCE

This study supports the idea of educating nurses to use a CCT program for treating older adults with MCI to improve their cognitive function.

A rapid and non-invasive fluorescence method for quantifying coenzyme Q10 in blood and urine in clinical analysis

Background

Coenzyme Q10 (CoQ10) supplementation can improve cognition in patients with Alzheimer's disease (AD) and AD transgenic model mice. To ameliorate the discomfort that patients with AD suffer after several blood extractions, a non‐invasive method for detecting urine CoQ10 levels needs to be established.

Methods

Here, we developed a new technique of fluorescence spectrophotometry with ethyl cyanoacetate (FS‐ECA), on the basis of the principle that the chemical derivative obtained from the interaction between CoQ10 and ECA was detected by a fluorescence detector at λ_ex/em = 450/515 nm. As a standard reference method, the same batches of the clinical samples were analyzed by high‐performance liquid chromatography with an ultraviolet detector (HPLC‐UV) at 275 nm.

Results

The limits of detection (LOD) and limits of quantization (LOQ) (serum: 0.021 and 0.043 mg/L; urine: 0.012 and 0.025 mg/L) determined by the FS‐ECA method were similar to that obtained through HPLC‐UV (serum: 0.017 and 0.035 mg/L; urine: 0.012 and 0.025 mg/L). More importantly, this new FS‐ECA technique as well as the conventional HPLC‐UV method could detect a marked difference in urine CoQ10 levels between AD and controls.

Conclusion

Our findings suggest that this non‐invasive method for quantifying urine CoQ10 potentially replaces HPLC to detect blood CoQ10.

A rapid and sensitive fluorescence method for detecting urine formaldehyde in patients with Alzheimer's disease

BACKGROUND

Morning urine formaldehyde concentrations could predict the severe degree of dementia in patients with post-stroke dementia and Alzheimer's disease. However, the routinely available technique of high-performance liquid chromatography (HPLC) for detecting urine formaldehyde requires expensive and sophisticated equipment.

METHODS

We established a fluorescence spectrophotometric method by using a formaldehyde-specific fluorescent probe-NaFA (λex/em = 430/543 nm). As a standard reference method, the same batch of urine samples was analysed by HPLC with a fluorescence detector (λex/em = 346/422 nm). Then we compared the limits of detection and the limits of quantization detected by these two methods and addressed the relationship between urine formaldehyde and human cognitive ability. The Mini-Mental State Examination (MMSE), Clinical Dementia Rating and Activities of Daily Living scale were used to evaluate cognition function in 30 Alzheimer's disease patients and 52 healthy age-matched controls.

RESULTS

Limits of detection and limits of quantization (1.27 and 2.48 μM) of the NaFA probe method were more accurate than Fluo-HPLC (1.52 and 2.91 μM). There was no difference in the detected formaldehyde values within day and day-to-day. Notably, only 3/82 urine formaldehyde concentrations detected by NaFA probe were below zero, while 12/82 of the values analysed by Fluo-HPLC were abnormal. More importantly, there were negatively correlated between urine formaldehyde concentrations detected by NaFA probe and MMSE scores, but positively correlated with Clinical Dementia Rating scores in Alzheimer's disease patients.

CONCLUSIONS

This detecting urine formaldehyde method by NaFA probe was more rapid, sensitive and accurate than Fluo-HPLC.

Sex differences in DEK expression in the anterior cingulate cortex and its association with dementia severity in schizophrenia

DEK is a chromatin-remodeling phosphoprotein found in most human tissues, but its expression and function in the human brain is largely unknown. DEK depletion in vitro induces cellular and molecular anomalies associated with cognitive impairment, including down-regulation of the canonical Wnt/β-catenin signaling pathway. ToppGene analyses link DEK loss to genes associated with various dementias and age-related cognitive decline. To examine the role of DEK in cognitive impairment in severe mental illness, DEK protein expression was assayed by immunoblot in the anterior cingulate cortex (ACC) of subjects with schizophrenia. Cognitive impairment is a core feature of schizophrenia and cognitive function in subjects was assessed antemortem using the clinical dementia rating (CDR) scale. DEK protein expression was not significantly altered in schizophrenia (n = 20) compared to control subjects (n = 20). Further analysis revealed significant reduction in DEK protein expression in women with schizophrenia, and a significant increase in expression in men with schizophrenia, relative to their same-sex controls. DEK protein expression levels were inversely correlated with dementia severity in women. Conversely, in men, DEK protein expression and dementia severity were positively correlated. Notably, there was no sex difference in DEK protein expression in the control group, suggesting that this sex difference is specific to schizophrenia and not due to inherent differences in DEK expression between males and females. These results suggest a novel, sex-specific role for DEK in cognitive performance and highlight a putative sex-specific link between central nervous system DEK protein expression and a neuropsychiatric disease that is commonly associated with cognitive impairment.

Careful neuropsychological testing reveals a novel genetic marker, GSTO1*C, linked to the pre-stage of Alzheimer's disease

Approximately 30 million people currently suffer from late-onset Alzheimer's disease (LOAD) worldwide. Twin studies demonstrated that 60 to 80% of LOAD is genetically determined, 20% of which remaining unassigned. This case-control study included 118 cognitively healthy controls, 52 patients with mild cognitive impairment (MCI; the pre-stage of LOAD) and 71 LOAD patients. The participants were genotyped for the genetic LOAD marker apolipoprotein E4 (APOE4) and the single-nucleotide polymorphism rs4925 in glutathione S-transferase omega-1 (GSTO1). Additive logistic regression showed a novel, statistically significant association of the major allele GSTO1*C with MCI (OR1.9; p = 0.032). However, identification of significant SNP-disease relations required well-defined study groups. When classifying participants solely by the short Mini Mental State examination (MMSE), the associations of GSTO1*C and the reference marker APOE4 with MCI were cancelled. Moreover, even identifying only the control group by MMSE nullified a statistically significant association (OR1.8; p = 0.045) between GSTO1*C and LOAD. In contrast, these statistical relations were retained when the detailed Consortium to Establish a Registry for Alzheimer's Disease (CERAD-Plus) test battery was used. Hence, besides proposing rs4925 as a genetic marker for cognitive impairment, this work also emphasized the importance of carefully characterized controls in addition to well-diagnosed patients in case-control studies.

Depressive Symptoms Are Associated with Cognitive Function in the Elderly with Type 2 Diabetes

BACKGROUND

Type 2 diabetes (T2D) is a metabolic condition associated with poor clinical and cognitive outcomes including vascular disease, depressive symptoms, cognitive impairment, and dementia. In the general elderly population, depression has been consistently identified as a risk factor for cognitive impairment/decline. However, the association between depression and cognitive function in T2D has been understudied.

OBJECTIVE

We investigated the association between depression and cognitive function in a large sample of cognitively normal elderly with T2D.

METHODS

In this cross-sectional study, we examined 738 participants, aged 65-88 years old, enrolled in the Israel Diabetes and Cognitive Decline study. For each cognitive domain (Episodic Memory, Executive Function, Attention/Working Memory, Language/Semantic Categorization) and Overall Cognition, multiple linear regressions assessed its association with depression (score greater than 5 on the 15-item version of the Geriatric Depression Scale [GDS]), adjusting for age, sex, and education.

RESULTS

Depression (n = 66, 8.9%) was associated with worse performance on tasks of Executive Function (p = 0.004), Language/Semantic Categorization (p < 0.001), and Overall Cognition (p < 0.002), but not Episodic Memory (p = 0.643) or Attention/Working Memory (p = 0.488). Secondary analyses using GDS as a continuous variable did not substantially change the results. Adjusting also for a history of antidepressant medication use slightly weakened the findings.

CONCLUSION

Significant associations of depression with several cognitive domains and Overall Cognition even in cognitively normal elderly with T2D, suggest that depression may have a role in impaired cognitive function in T2D, which may be attenuated by antidepressants.

Neuropsychological Test Performance in Cognitively Normal Spanish-speaking Nonagenarians with Little Education

To find associations of age, sex, and education with neuropsychological test performance in cognitively normal Spanish-speaking Costa Rican nonagenarians with little education; to provide norms; and to compare their performance with similar Puerto Ricans. For 95 Costa Ricans (90-102 years old, 0-6 years of education), multiple regression assessed associations with demographics of performance on six neuropsychological tests. Analyses of covariance compared them with 23 Puerto Ricans (90-99 years old). Younger age and being female-but not education-were associated with better performance on some neuropsychological tests, in particular episodic memory. The Puerto Ricans performed better on learning and memory tasks. In cognitively intact Spanish-speaking nonagenarians with little or no education, education did not affect test performance. Additional studies of the effect of education on cognitive performance are warranted in other samples with extremely low education or old age. National differences in performance highlight the importance of group-specific norms.

Ethnicity/culture modulates the relationships of the haptoglobin (Hp) 1-1 phenotype with cognitive function in older individuals with type 2 diabetes

OBJECTIVE

The haptoglobin (Hp) genotype has been associated with cognitive function in type 2 diabetes. Because ethnicity/culture has been associated with both cognitive function and Hp genotype frequencies, we examined whether it modulates the association of Hp with cognitive function.

METHODS

This cross-sectional study evaluated 787 cognitively normal older individuals (>65 years of age) with type 2 diabetes participating in the Israel Diabetes and Cognitive Decline study. Interactions in two-way analyses of covariance compared Group (Non-Ashkenazi versus Ashkenazi Jews) on the associations of Hp phenotype (Hp 1-1 versus non- Hp 1-1) with five cognitive outcome measures. The primary control variables were age, gender, and education.

RESULTS

Compared with Ashkenazi Jews, non-Ashkenazi Jews with the Hp 1-1 phenotype had significantly poorer cognitive function than non-Hp 1-1 in the domains of Attention/Working Memory (p = 0.035) and Executive Function (p = 0.023), but not in Language/Semantic Categorization (p = 0.432), Episodic Memory (p = 0.268), or Overall Cognition (p = 0.082). After controlling for additional covariates (type 2 diabetes-related characteristics, cardiovascular risk factors, Mini-mental State Examination, and extent of depressive symptoms), Attention/Working Memory (p = 0.038) and Executive Function (p = 0.013) remained significant.

CONCLUSIONS

Older individuals from specific ethnic/cultural backgrounds with the Hp 1-1 phenotype may benefit more from treatment targeted at decreasing or halting the detrimental effects of Hp 1-1 on the brain. Future studies should examine differential associations of Hp 1-1 and cognitive impairment, especially for groups with high prevalence of both, such as African-Americans and Hispanics.

Haptoglobin genotype modulates the relationships of glycaemic control with cognitive function in elderly individuals with type 2 diabetes

AIMS/HYPOTHESIS

The purpose of this study was to investigate whether the association of glycaemic control with cognitive function is modulated by the haptoglobin 1-1 (Hp 1-1) genotype in cognitively normal elderly individuals with type 2 diabetes.

METHODS

In this cross-sectional study, we examined 793 participants who were genotyped for Hp (80 Hp 1-1 carriers and 713 Hp 1-1 non-carriers) enrolled in the Israel Diabetes and Cognitive Decline (IDCD) study. Glycaemic control was operationally defined by HbA1c level. The outcome measures were performance in four cognitive domains (episodic memory, attention/working memory, language/semantic categorisation, executive function) and overall cognition, a composite of the domains. Effect sizes were obtained from hierarchical linear regression analyses for each outcome measure, controlling for demographics, type 2 diabetes-related characteristics, cardiovascular risk factors, and their interactions with Hp genotype.

RESULTS

Interaction analyses showed significantly stronger associations of HbA1c with poorer cognitive function among Hp 1-1 carriers than non-carriers; attention/working memory (p < 0.001) and overall cognition (p = 0.003). For these two cognitive domains, associations were significant for Hp 1-1 carriers despite the small sample size (p < 0.00001 and p = 0.001, respectively), but not for non-carriers.

CONCLUSIONS/INTERPRETATION

Our findings suggest that patients with type 2 diabetes and poor glycaemic control carrying the Hp 1-1 genotype may be at increased risk of cognitive impairment, particularly in the attention/working memory domain. The association of glycaemic control with this domain may indicate cerebrovascular mechanisms.

Arterial wall function is associated with cognitive performance primarily in elderly with type 2 diabetes

Regression analyses compared 41 type 2 diabetes (T2D) and 131 non-T2D cognitively normal elderly males on the associations of arterial wall function measures [large artery elasticity index (LAEI), small artery elasticity index (SAEI), systemic vascular resistance (SVR), and total vascular impedance (TVI)] with cognitive performance (memory, language, and executive functions), controlling for socio-demographic and cardiovascular factors. Higher LAEI and lower TVI were significantly associated with better executive functions performance in T2D but not in non-T2D subjects. Lower TVI was more associated with better language performance in T2D. Results suggest that arterial wall function is associated with cognition in T2D.

Assessing neuropsychiatric symptoms in people with dementia: a systematic review of measures

BACKGROUND

Neuropsychiatric symptoms (NPS) occur in people with dementia throughout disease course and across etiologies. NPS are associated with significant morbidities and hastened disease processes. Nevertheless, people with dementia are not systematically assessed for NPS in clinical settings. We review existing NPS measures for clinical and/or research purposes, and identify measurement gaps.

METHODS

We conducted a computerized search of peer-reviewed published studies of measures (January 1, 1980-December 1, 2013) using multiple search terms. Measures selected for review were in English, had adequate psychometric properties, and were developed for or used with people with dementia. Papers describing measures were evaluated by three coders along seven characteristics: behavioral domains, number of items, method of administration, response categories, targeted population, setting, and psychometric properties.

RESULTS

Overall, 2,233 papers were identified through search terms, and 36 papers from manual searches of references. From 2,269 papers, 85 measures were identified of which 45 (52.9%) had adequate psychometric properties and were developed or used with dementia populations. Of these, 16 (35.6%) were general measures that included a wide range of behaviors; 29 (64.4%) targeted specific behaviors (e.g. agitation). Measures differed widely as to behaviors assessed and measurement properties.

CONCLUSIONS

A robust set of diverse measures exists for assessing NPS in different settings. No measures identify risk factors for behaviors or enable an evaluation of the context in which behaviors occur. To improve clinical efforts, research is needed to evaluate concordance of behavioral ratings between formal and informal caregivers, and to develop and test measures that can identify known risks for behaviors and the circumstances under which behaviors occur.

The ApoE4 genotype modifies the relationship of long-term glycemic control with cognitive functioning in elderly with type 2 diabetes

AIM

To assess whether the APOE4 genotype affects the relationship of long-term glycemic control with cognitive function in elderly with type 2 diabetes (T2D).

METHODS

Participants were cognitively normal and pertained to a Diabetes Registry which provided access to HbA1c levels and other T2D related factors since 1998. Glycemic control was defined as the mean of all HbA1c measurements available (averaging 18 measurements) per subject. Four cognitive domains (episodic memory, semantic categorization, attention/working memory and executive function), based on factor analysis and an overall cognitive score (the sum of the 4 cognitive domains) were the outcome measures.

RESULTS

The analysis included 808 subjects; 107 (11.9%) subjects had ≥1ApoE4 allele. In ApoE4 carriers, higher mean HbA1c level was significantly associated with lower scores on all cognitive measures except attention/working memory (p-values ranging from 0.047 to 0.003). In ApoE4 non-carriers, higher mean HbA1c level was significantly associated with lower scores on executive function, but not with other cognitive measures-despite the larger sample size. Compared to non-carriers, there were significantly stronger associations in ApoE4 carriers for overall cognition (p=0.02), semantic categorization (p=0.03) and episodic memory (p=0.02), and the difference for executive function approached statistical significance (p=0.06).

CONCLUSION

In this cross-sectional study of cognitively normal T2D subjects, higher mean HbA1c levels were generally associated with lower cognitive performance in ApoE4 carriers, but not in non-carriers, suggesting that ApoE4 affects the relationship between long-term glycemic control and cognition, so APOE4 carriers may be more vulnerable to the insults of poor glycemic control.

Trajectories in glycemic control over time are associated with cognitive performance in elderly subjects with type 2 diabetes

Objective

To study the relationships of long-term trajectories of glycemic control with cognitive performance in cognitively normal elderly with type 2 diabetes (T2D).

Methods

Subjects (n = 835) pertain to a diabetes registry (DR) established in 1998 with an average of 18 HbA1c measurements per subject, permitting identification of distinctive trajectory groups of HbA1c and examining their association with cognitive function in five domains: episodic memory, semantic categorization, attention/working memory, executive function, and overall cognition. Analyses of covariance compared cognitive function among the trajectory groups adjusting for sociodemographic, cardiovascular, diabetes-related covariates and depression.

Results

Subjects averaged 72.8 years of age. Six trajectories of HbA1c were identified, characterized by HbA1c level at entry into the DR (Higher/Lower), and trend over time (Stable/Decreasing/Increasing). Both groups with a trajectory of decreasing HbA1c levels had high HbA1c levels at entry into the DR (9.2%, 10.7%), and high, though decreasing, HbA1c levels over time. They had the worst cognitive performance, particularly in overall cognition (p<0.02) and semantic categorization (p<0.01), followed by that of subjects whose HbA1c at entry into the DR was relatively high (7.2%, 7.8%) and increased over time. Subjects with stable HbA1c over time had the lowest HbA1c levels at entry (6.0%, 6.8%) and performed best in cognitive tests.

Conclusion

Glycemic control trajectories, which better reflect chronicity of T2D than a single HbA1c measurement, predict cognitive performance. A trajectory of stable HbA1c levels over time is associated with better cognitive function.

Prognostic factors of neurocognitive and functional outcomes in junior and senior elderly patients with traumatic brain injury undergoing disability evaluation or appointed disability evaluation

Objective

This study explored the relationships among demographic (DVs) and clinical variables (CVs), neurocognitive (NOs) and functional outcome (FO) that could be used as prognostic factors for old aged patients with traumatic brain injury (TBI) undergoing or appointed disability evaluation (DE) after treatment.

Methods

A total of 162 subjects with TBI above the age of 55 years undergoing DE or appointed to do so after treatments were selected. The patients were divided into two subgroups according to age : a junior elderly group 55 to 64 years old and a senior elderly group over the age of 65. NOs and FO were evaluated using the Seoul Neuropsychological Screening Battery and Clinical Dementia Rating scale.

Results

Gender, age, and education level were shown to significantly impact the recovery of NOs after TBI. Other DVs and CVs such as area of residency, occupation, type of injury, or loss of consciousness were not found to significantly affect the recovery of NOs after TBI. Analysis of the relationships among DVs, CVs and NOs demonstrated that gender, age, and education level contributed to the variance of NOs. In FO, loss of consciousness (LOC) was included to prognostic factor.

Conclusion

Gender, age and education level significantly influence the NOs of elderly patients with TBI. LOC may also serve as a meaningful prognostic factor in FO. Unlike younger adult patients with TBI, old aged patients with TBI did not show global faking-bad or malingering attitudes to DE for compensation, but assume that they could faking their performance in a test set available visual feedback.

Haptoglobin 1-1 genotype is associated with poorer cognitive functioning in the elderly with type 2 diabetes

OBJECTIVE

Haptoglobin (Hp) genotype (Hp 1-1, 1-2, or 2-2) is associated with risk for type 2 diabetes complications, but its relationship with cognitive compromise, a growing concern in type 2 diabetes, has rarely been studied. This study investigated whether Hp genotype is associated with cognitive function in cognitively normal elderly diabetic subjects.

RESEARCH DESIGN AND METHODS

Relationships of Hp genotype with episodic memory, semantic categorization, attention/working memory and executive function, and an overall cognitive score were examined in subjects from the Israel Diabetes and Cognitive Decline (IDCD) study.

RESULTS

In the present analysis, 812 subjects participated (84 with Hp 1-1, 335 with Hp 1-2, and 393 with Hp 2-2 genotypes). Average was 72.9 years of age (SD 4.7), and Mini-Mental State Exam (MMSE) was 28.0 (SD 1.8). Compared with subjects with Hp 1-2 genotype, Hp 1-1 subjects performed significantly worse in semantic categorization (F=7.03; P=0.008) and the overall cognitive score (F=5.57; P=0.02). A separate stepwise multiple regression analysis demonstrated that compared with subjects with Hp 2-2 genotype, Hp 1-1 subjects performed significantly worse in semantic categorization (F=4.18; P=0.04) and the overall cognitive score (F=4.70; P=0.03). The contribution of cardiovascular risk factors to cognition was significantly higher in subjects with Hp 1-1 genotype compared with Hp 2 carriers (Hp 1-2 and Hp 2-2) in the semantic categorization (P=0.009) and attention/working memory (P=0.002) cognitive domains.

CONCLUSIONS

Compared with Hp 2 carriers, those with Hp 1-1 genotype present lower cognitive performance. Stronger relationships between cardiovascular risk factors and cognition in the latter group may suggest an underlying vascular mechanism.

Confirmatory factor analysis of the ADNI Neuropsychological Battery

The Alzheimer's Disease Neuroimaging Initiative (ADNI) is a large multi-center study designed to develop optimized methods for acquiring longitudinal neuroimaging, cognitive, and biomarker measures of AD progression in a large cohort of patients with Alzheimer's disease (AD), patients with Mild Cognitive Impairment, and healthy controls. Detailed neuropsychological testing was conducted on all participants. We examined the factor structure of the ADNI Neuropsychological Battery across older adults with differing levels of clinical AD severity based on the Clinical Dementia Rating Scale (CDR). Confirmatory factor analysis (CFA) of 23 variables from 10 neuropsychological tests resulted in five factors (memory, language, visuospatial functioning, attention, and executive function/processing speed) that were invariant across levels of cognitive impairment. Thus, these five factors can be used as indicators of cognitive function in older adults who are participants in ADNI.

Cell cycle checkpoint abnormalities during dementia: A plausible association with the loss of protection against oxidative stress in Alzheimer's disease [corrected]

Background

Increasing evidence suggests an association between neuronal cell cycle (CCL) events and the processes that underlie neurodegeneration in Alzheimer’s disease (AD). Elevated levels of oxidative stress markers and mitochondrial dysfunction are also among early events in AD. Recent studies have reported the role of CCL checkpoint proteins and tumor suppressors, such as ATM and p53 in the control of glycolysis and oxidative metabolism in cancer, but their involvement in AD remains uncertain.

Methods and Findings

In this postmortem study, we measured gene expression levels of eight CCL checkpoint proteins in the superior temporal cortex (STC) of persons with varying severities of AD dementia and compare them to those of cognitively normal controls. To assess whether the CCL changes associated with cognitive impairment in AD are specific to dementia, gene expression of the same proteins was also measured in STC of persons with schizophrenia (SZ), which is also characterized by mitochondrial dysfunction. The expression of CCL-checkpoint and DNA damage response genes: MDM4, ATM and ATR was strongly upregulated and associated with progression of dementia (cognitive dementia rating, CDR), appearing as early as questionable or mild dementia (CDRs 0.5–1). In addition to gene expression changes, the downstream target of ATM-p53 signaling - TIGAR, a p53-inducible protein, the activation of which can regulate energy metabolism and protect against oxidative stress was progressively decreased as severity of dementia evolved, but it was unaffected in subjects with SZ. In contrast to AD, different CCL checkpoint proteins, which include p53, CHEK1 and BRCA1 were significantly downregulated in SZ.

Conclusions

These results support the activation of an ATM signaling and DNA damage response network during the progression of AD dementia, while the progressive decrease in the levels of TIGAR suggests loss of protection initiated by ATM-p53 signaling against intensifying oxidative stress in AD.

The association of neuropsychiatric symptoms in MCI with incident dementia and Alzheimer disease

OBJECTIVES

Individuals with mild cognitive impairment (MCI) are at high risk of developing dementia and/or Alzheimer disease (AD). Among persons with MCI, depression and anxiety have been associated with an increased risk of incident dementia. We examined whether neuropsychiatric symptoms in MCI increased the risk of incident dementia (all-cause) and incident AD.

DESIGN

Longitudinal cohort study followed annually (median: 1.58 years).

SETTING

National Alzheimer's Coordinating Center database combining clinical data from 29 Alzheimer's Disease Centers.

PARTICIPANTS

A total of 1,821 participants with MCI.

MEASUREMENTS

1) Progression to dementia (all-cause) or AD, 2) Neuropsychiatric Inventory Questionnaire (NPI-Q), 3) Geriatric Depression Scale (GDS), 4) Clinical Dementia Rating Global Score and Sum of Boxes, and 5) Mini-Mental State Examination (MMSE). The association of covariates with risk of incident dementia or AD was evaluated with hazard ratios (HR) determined by Cox proportional-hazards models adjusted for age, ethnicity, Clinical Dementia Rating Global Score and Sum of Boxes, and MMSE.

RESULTS

A total of 527 participants (28.9%) progressed to dementia and 454 (24.9%) to AD. Baseline GDS > 0 was associated with an increased risk of incident dementia (HR: 1.47, 95% CI: 1.17-1.84) and AD (HR: 1.45, 95% CI: 1.14-1.83). Baseline NPI > 0 was associated with an increased risk of incident dementia (HR: 1.37, 95% CI: 1.12-1.66) and AD (HR: 1.35, 95% CI: 1.09-1.66).

CONCLUSIONS

Neuropsychiatric symptoms in MCI are associated with significantly an increased risk of incident dementia and AD. Neuropsychiatric symptoms may be among the earliest symptoms of preclinical stages of AD and targeting them therapeutically might delay transition to dementia.

Reduced activity restriction buffers the relations between chronic stress and sympathetic nervous system activation

OBJECTIVES

Caregivers of dementia patients are at risk for developing cardiovascular disease (CVD), and this risk increases the longer they provide care. Greater perceptions that caregiving restricts social/recreational activities (i.e., activity restriction [AR]) has been associated with poorer health, and AR may exacerbate the relations between stress and health outcomes. The current study examined the interactive role of greater exposure to stress and increased AR on plasma catecholamine (CAT) levels: norepinephrine (NE) and epinephrine (EPI).

METHOD

A total of 84 dementia caregivers completed a standard assessment battery, and a nurse collected blood, which was assayed for NE and EPI. Separate regressions for NE and EPI were used to determine whether the relations between years caregiving and CATs were greater in those with high versus low AR.

RESULTS

A significant interaction was found between years caregiving and AR in predicting resting EPI (p = .032) but not resting NE (p = .103). Post hoc analyses indicated that years caregiving was significantly associated with EPI when AR was high (p = .008) but not when AR was low (p = .799). Additionally, years caregiving was not significantly associated with NE when AR was high or low.

DISCUSSION

The subjective experience of AR can play an important role in determining risk for detrimental physical health outcomes, particularly CVD risk.

The experience of caregiving: differences between behavioral variant of frontotemporal dementia and Alzheimer disease

OBJECTIVE

To examine caregiver strain, depression, perceived sense of control, and distress from patient neuropsychiatric symptoms in family caregivers of persons with Alzheimer disease (AD) and behavioral variant of frontotemporal dementia (bvFTD) and determine whether group differences exist.

METHODS

Family caregivers were recruited from the Memory and Aging Center in San Francisco, California. Analyses of cross-sectional data on 53 family caregivers (AD = 31, bvFTD = 22) were performed. The Mann-Whitney U test was used to contrast groups.

RESULTS

There were statistically significant differences between the AD and bvFTD caregivers in strain, distress, and perceived control but not in depression. On average, bvFTD caregivers experienced greater strain and distress, more depressive symptoms, and lower perceived control.

CONCLUSIONS

Findings support that experiences of AD and bvFTD caregivers may differ. Further study is needed to identify possible explanatory factors for these group differences.

Prevalence of sleep disturbances in mild cognitive impairment and dementing disorders: a multicenter Italian clinical cross-sectional study on 431 patients

BACKGROUND/AIMS

Sleep disturbances are common in the elderly and in persons with cognitive decline. The aim of this study was to describe frequency and characteristics of insomnia, excessive daytime sleepiness, sleep-disordered breathing, REM behavior disorder and restless legs syndrome in a large cohort of persons with mild cognitive impairment or dementia.

METHODS

431 consecutive patients were enrolled in 10 Italian neurological centers: 204 had Alzheimer's disease, 138 mild cognitive impairment, 43 vascular dementia, 25 frontotemporal dementia and 21 Lewy body dementia or Parkinson's disease dementia. Sleep disorders were investigated with a battery of standardized questions and questionnaires.

RESULTS

Over 60% of persons had one or more sleep disturbances almost invariably associated one to another without any evident and specific pattern of co-occurrence. Persons with Alzheimer's disease and those with mild cognitive impairment had the same frequency of any sleep disorder. Sleep-disordered breathing was more frequent in vascular dementia. REM behavior disorder was more represented in Lewy body or Parkinson's disease dementia.

CONCLUSION

A careful clinical evaluation of sleep disorders should be performed routinely in the clinical setting of persons with cognitive decline. Instrumental supports should be used only in selected patients.

A systematic review of assessment and treatment of moderate to severe Alzheimer's disease

OBJECTIVE

The systematic, large-scale study of therapies for moderate to severe Alzheimer's disease (AD) is a relatively recent advancement in the field. This review describes for the general practitioner the characterization of moderate to severe AD, discusses the development of metrics sensitive to the constellation of symptoms in these patients, and critically evaluates the use of those measures in moderate to severe AD clinical trials.

DATA SOURCES

Published clinical trials obtained by MEDLINE searches used the following key words: moderate AD, severe AD, donepezil, rivastigmine, galantamine, memantine, and anti-dementia agents. Clinical trials were limited by language (English), study type (clinical trial), and publication dates (1990-2005).

STUDY SELECTION

Nine clinical trials comprise the studies conducted to date in moderate to severe AD and include 5 prospective randomized clinical trials (3 for memantine, 2 for donepezil) and 4 retrospective subanalyses (2 for galantamine, 2 for rivastigmine) of primary datasets.

DATA EXTRACTION

Clinical trials are summarized and major findings are reviewed.

DATA SYNTHESIS

The data reviewed support the decision to initiate and maintain treatment in moderate to severe AD patients.

CONCLUSIONS

The development and implementation of improved metrics for moderate to severe AD patients has revealed that meaningful benefits are attainable in this patient population by treatment with the N-methyl-D-aspartate receptor antagonist memantine. Evidence also indicates a benefit from cholinesterase inhibitor treatment, although further study of these agents in this patient population is warranted.

Reducing case ascertainment costs in U.S. population studies of Alzheimer's disease, dementia, and cognitive impairment-Part 1

Establishing methods for ascertainment of dementia and cognitive impairment that are accurate and also cost-effective is a challenging enterprise. Large population-based studies often using administrative data sets offer relatively inexpensive and reliable estimates of severe conditions including moderate to advanced dementia that are useful for public health planning, but they can miss less severe cognitive impairment which may be the most effective point for intervention. Clinical and epidemiological cohorts, intensively assessed, provide more sensitive detection of less severe cognitive impairment but are often costly. In this article, several approaches to ascertainment are evaluated for validity, reliability, and cost. In particular, the methods of ascertainment from the Health and Retirement Study are described briefly, along with those of the Aging, Demographics, and Memory Study (ADAMS). ADAMS, a resource-intense sub-study of the Health and Retirement Study, was designed to provide diagnostic accuracy among persons with more advanced dementia. A proposal to streamline future ADAMS assessments is offered. Also considered are algorithmic and Web-based approaches to diagnosis that can reduce the expense of clinical expertise and, in some contexts, can reduce the extent of data collection. These approaches are intended for intensively assessed epidemiological cohorts where goal is valid and reliable case detection with efficient and cost-effective tools.

Predicting functional decline in behavioural variant frontotemporal dementia

Behavioural variant frontotemporal dementia is characterized by a change in comportment. It is associated with considerable functional decline over the course of the illness albeit with sometimes dramatic variability among patients. It is unknown whether any baseline features, or combination of features, could predict rate of functional decline in behavioural variant frontotemporal dementia. The aim of this study was to investigate the effects of different baseline clinical, neuropsychological, neuropsychiatric, genetic and anatomic predictors on the rate of functional decline as measured by the Clinical Dementia Rating Sum of Boxes scale. We identified 86 subjects with behavioural variant frontotemporal dementia that had multiple serial Clinical Dementia Rating Sum of Boxes assessments (mean 4, range 2-18). Atlas-based parcellation was used to generate volumes for specific regions of interest at baseline. Volumes were utilized to classify subjects into different anatomical subtypes using the advanced statistical technique of cluster analysis and were assessed as predictor variables. Composite scores were generated for the neuropsychological domains of executive, language, memory and visuospatial function. Behaviours from the brief questionnaire form of the Neuropsychiatric Inventory were assessed. Linear mixed-effects regression modelling was used to determine which baseline features predict rate of future functional decline. Rates of functional decline differed across the anatomical subtypes of behavioural variant frontotemporal dementia, with faster rates observed in the frontal dominant and frontotemporal subtypes. In addition, subjects with poorer performance on neuropsychological tests of executive, language and visuospatial function, less disinhibition, agitation/aggression and night-time behaviours at presentation, and smaller medial, lateral and orbital frontal lobe volumes showed faster rates of decline. In many instances, the effect of the predictor variables observed across all subjects was also preserved within anatomical subtypes. Furthermore, some of the predictor variables improved our prediction of rate of functional decline after anatomical subtype was taken into account. In particular, age at onset was a highly significant predictor but only after adjusting for subtype. We also found that although some predictor variables, for example gender, Mini-Mental State Examination score, and apathy/indifference, did not affect the rate of functional decline; these variables were associated with the actual Clinical Dementia Rating Sum of Boxes score estimated for any given time-point. These findings suggest that in behavioural variant frontotemporal dementia, rate of functional decline is driven by the combination of anatomical pattern of atrophy, age at onset, and neuropsychiatric characteristics of the subject at baseline.

NIA-funded Alzheimer centers are more efficient than commercial clinical recruitment sites for conducting secondary prevention trials of dementia

Study participant dropout compromises clinical trials by reducing statistical power and potentially biasing findings. We use data from a trial of treatments to delay the progression of mild cognitive impairment to Alzheimer disease (AD) [NEJM 2005;352 (23):79 to 88] to determine predictors of study participant dropout and inform the design and implementation of future trials. Time to study discontinuation was modeled by proportional hazards regression with censoring at incident dementia or trial completion. Of 769 participants, 230 (30%) discontinued prematurely. Risk of dropout was higher among nonwhites [hazard ratio (HR) 2.1, P=0.0007], participants with less than college education (HR=1.6, P=0.02), participants with a Hamilton Depression score of 6 or more (HR=1.3, P=0.04), unmarried males (HR=2.1 relative to married males, P=0.003) and participants recruited by commercial clinical sites (HR=2.2 relative to participants recruited by NIA-funded AD research centers, P<0.0001). A trial using commercial sites with the discontinuation rates and incident dementia event rates experienced in this trial would require 80% more participants than a comparably powered trial using NIA-funded AD research center sites. Targeted retention efforts and utilization of academic sites could substantively improve the statistical power and validity of future clinical trials of cognitively impaired elderly.