Comprehensive Evaluation of the Functional Activities Questionnaire (FAQ) and Its Reliability and Validity

Assessing clinical progression measures in Alzheimer's disease trials: A systematic review and meta-analysis

INTRODUCTION

Assessing treatments for Alzheimer's disease (AD) relies on reliable tools for measuring AD progression. In this analysis, we evaluate the sensitivity of clinical progression measures in AD within randomized controlled trials (RCTs) with confirmed positive amyloid (Aβ+) status prior to trial enrollment.

METHODS

Excluding trials targeting non-cognitive symptoms, we conducted meta-analyses on progression measures from 25 selected RCTs using R version 4.2.0, along with the metafor and emmeans libraries.

RESULTS

The Functional Activities Questionnaire (FAQ) demonstrated the greatest sensitivity over 12 weeks. Other cognitive measures demonstrated lower sensitivity. The integrated Alzheimer's Disease Rating Scale (iADRS) and Clinical Dementia Rating-Sum of Boxes (CDR-SB) seemed more effective than their individual cognitive components. Neuropsychiatric measures were the least sensitive in measuring progression.

DISCUSSION

Functional measures generally outperformed other measure categories. Purely cognitive domain-based measures were suboptimal for tracking early AD progression. Ideally, future measures should incorporate both cognitive and functional components to enhance sensitivity.

HIGHLIGHTS

Concerns remain regarding the limitations of current outcome measures used in AD clinical trials, particularly their sensitivity in the early and preclinical stages of the disease, which hampers their reliability as indicators of AD progression. The Functional Activities Questionnaire (FAQ) demonstrated the most substantial weighted mean change over 12 weeks, followed by the Mini-Mental State Examination (MMSE). Functional measures outperformed other measure categories. Composite scores of integrated Alzheimer's Disease Rating Scale and Clinical Dementia Rating-Sum of Boxes are more sensitive to change than their individual cognitive components, possibly driven by the functional components of the score. Neuropsychiatric measures analyzed in this study appeared to be the least sensitive in measuring progression.

Technology-based instrumental activities of daily living in persons with Alzheimer's disease and related disorders

INTRODUCTION

Instrumental activities of daily living (iADLs) increasingly involve technology (e.g., making payments online, texting). The current study examined the applicability and diagnostic accuracy of technology-based iADLs in those evaluated for Alzheimer's disease and related dementias (ADRD).

METHODS

A total of 264 care partners of persons undergoing comprehensive interdisciplinary evaluations completed the Functional Activities Questionnaire and 11 technology-based iADL items.

RESULTS

Technology-based iADLs applied to more than 80% of patients. Average dependence on technology-based items was overall less than for traditional iADLs. The addition of technology-based items to traditional iADL items slightly improved the ability to identify individuals with dementia. When considered separately, technology-based iADL items demonstrated comparable ability to distinguish between diagnostic stages.

DISCUSSION

Technology use is common in older adults with ADRD for a range of daily activities. Accounting for technology use increases the content validity of existing iADL measures for the modern context and yields comparable diagnostic accuracy.

Highlights

Technology use is often integral to daily activity performance for individuals with Alzheimer's disease and related dementias (ADRD).Daily technologies, such as smartphones, were used frequently by those with ADRD.Many individuals were less dependent on technology activities than traditional activities.Adding technology questions slightly increased diagnostic accuracy for detecting dementia.

Cognitive dispersion and its functional relevance in behavioral variant frontotemporal dementia and prodromal behavioral variant frontotemporal dementia

OBJECTIVE

Executive dysfunction is characteristic of behavioral variant frontotemporal dementia (bvFTD) but can be challenging to detect. Dispersion-based intraindividual variability (IIV-d) is hypothesized to reflect a sensitive index of executive dysfunction and has demonstrated relevance to functional decline but has not been evaluated in bvFTD.

METHOD

We report on 477 demographically matched participants (159 cognitively healthy [CH], 159 clinical Alzheimer's disease [AD], 159 clinical bvFTD/prodromal bvFTD) who completed the Uniform Data Set 3.0 Neuropsychological Battery. IIV-d was measured using the coefficient of variance (CoV; raw and demographically adjusted) across 12 Uniform Data Set 3.0 Neuropsychological Battery indicators and the informant-rated Functional Activities Questionnaire assessed daily functioning.

RESULTS

Analysis of covariance showed that participants in the bvFTD/prodromal bvFTD group exhibited higher raw and demographically adjusted CoV compared to CH participants, at a very large effect size (d = 1.28-1.47). Demographically adjusted (but not raw) CoV was lower in the bvFTD/prodromal bvFTD group than the AD group, though the effect size was small (d = .38). Both CoV metrics accurately differentiated the bvFTD/prodromal bvFTD and CH groups (areas under the curve = .84), but not bvFTD/prodromal bvFTD and AD groups (areas under the curve = .59). Regression analyses in the bvFTD/prodromal bvFTD group indicated that higher IIV-d on both metrics was associated with greater daily functioning impairment, over and above covariates.

CONCLUSIONS

Compared to healthy adults, individuals with bvFTD/prodromal bvFTD show greater levels of performance variability across a battery of neuropsychological measures, which interferes with everyday functioning. These data demonstrate the clinical utility and ecological validity of IIV-d in bvFTD/prodromal bvFTD, though these findings should be replicated in more diverse samples. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Alzheimer's disease: a review on the current trends of the effective diagnosis and therapeutics

The most prevalent cause of dementia is Alzheimer's disease. Cognitive decline and accelerating memory loss characterize it. Alzheimer's disease advances sequentially, starting with preclinical stages, followed by mild cognitive and/or behavioral impairment, and ultimately leading to Alzheimer's disease dementia. In recent years, healthcare providers have been advised to make an earlier diagnosis of Alzheimer's, prior to individuals developing Alzheimer's disease dementia. Regrettably, the identification of early-stage Alzheimer's disease in clinical settings can be arduous due to the tendency of patients and healthcare providers to disregard symptoms as typical signs of aging. Therefore, accurate and prompt diagnosis of Alzheimer's disease is essential in order to facilitate the development of disease-modifying and secondary preventive therapies prior to the onset of symptoms. There has been a notable shift in the goal of the diagnosis process, transitioning from merely confirming the presence of symptomatic AD to recognizing the illness in its early, asymptomatic phases. Understanding the evolution of disease-modifying therapies and putting effective diagnostic and therapeutic management into practice requires an understanding of this concept. The outcomes of this study will enhance in-depth knowledge of the current status of Alzheimer's disease's diagnosis and treatment, justifying the necessity for the quest for potential novel biomarkers that can contribute to determining the stage of the disease, particularly in its earliest stages. Interestingly, latest clinical trial status on pharmacological agents, the nonpharmacological treatments such as behavior modification, exercise, and cognitive training as well as alternative approach on phytochemicals as neuroprotective agents have been covered in detailed.

Do we all do the same things? Applicability of daily activities at the intersection of demographics

OBJECTIVE

To evaluate the extent to which demographic factors-and their intersections-influence the applicability of items assessing activities of daily living (ADLs) in a sample of older adults.

METHOD

Participants' (n = 44,713) Functional Activities Questionnaire (FAQ) scores from a multicenter database were evaluated to see how participant and collateral demographics, contextual, and clinical characteristics impacted ADL nonapplicability (NA). Collateral, contextual, and clinical characteristics were matched in those with and without NA. The effect of participant demographics and their interactions on NA responses were modeled with logistic regression.

RESULTS

At least one FAQ item (most commonly bill payment, taxes, playing games, and meal preparation) was rated as NA in up to one third of participants across ethnoracial groups. Dementia staging had the largest impact on NA, followed by participant demographics. In a matched sample, logistic models revealed that participant demographics, in particular sex, best predicted NA. However, meaningful interactions with ethnoracial group were noted for bill payment, taxes, meal preparation, and game engagement, suggesting that demographic intersections (e.g., younger vs. older Latinxs) meaningfully predict whether a given ADL was applicable to an individual participant.

CONCLUSIONS

Neuropsychology is predicated on accurate assessments of both cognition and daily functioning and, in an increasingly diverse aging population, there should be careful consideration of demographic factors, their interactions, and historical contexts that drive day-to-day demands. This study establishes limitations of existing measures and paths forward for creating fair measures of functioning in older adults. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Let Us Talk Money: Subjectively Reported Financial Performance of People Living with Neurodegenerative Diseases-A Systematic Review

Neurodegenerative diseases (NDDs) form a heterogeneous, widespread group of disorders, generally characterized by progressive cognitive decline and neuropsychiatric disturbances. One of the abilities that seems particularly vulnerable to the impairments in neurodegenerative diseases is the capability to manage one's personal finances. Indeed, people living with neurodegenerative diseases were shown to consistently present with more problems on performance-based financial tasks than healthy individuals. While objective, performance-based tasks provide insight into the financial competence of people living with neurodegenerative diseases in a controlled, standardized setting; relatively little can be said, based on these tasks, about their degree of success in dealing with the financial demands, issues, or questions of everyday life (i.e., financial performance). The aim of this systematic review is to provide an overview of the literature examining self and informant reports of financial performance in people living with neurodegenerative diseases. In total, 22 studies were included that compared the financial performance of people living with mild cognitive impairment (MCI), Alzheimer's disease (AD), Parkinson's disease, or multiple sclerosis to a (cognitively) normal control group. Overall, the results indicate that people living with neurodegenerative diseases are more vulnerable to impairments in financial performance than cognitively normal individuals and that the degree of reported problems seems to be related to the severity of cognitive decline. As the majority of studies however focused on MCI or AD and made use of limited assessment methods, future research should aim to develop and adopt more comprehensive assessments to study strengths and weaknesses in financial performance of people living with different neurodegenerative diseases.

Reliability and validity of the Montreal Cognitive Assessment's auditory items (MoCA-22)

Objective: To evaluate the latent structure, internal consistency, convergent and discriminant validity, diagnostic accuracy, and criterion validity of the Montreal Cognitive Assessment's auditory items (MoCA-22), which has previously been evaluated in small samples if at all. Methods: 11,284 participants completed the MoCA over 1-2 visits to an Alzheimer Disease Research Center (Mage = 69.2, Meducation = 15.9, 57.6% women, 92.4% non-Hispanic white). MoCA-22 items were probed with alpha, omega, confirmatory factor analysis, and test-retest correlations. Scores were related to measures of neurocognition, daily functioning, behavioral-psychological symptoms (BPS), and vision performance for convergent-discriminant and criterion validity. Dementia stage was used to calculate area under the receiver operating characteristic (AUC-ROC) curves and cutoffs for mild cognitive impairment (MCI) and dementia. Results: A single-factor had good fit (CFI = .961; TLI = .945; RMSEA = .061; SRMR = .031), with good internal consistency (Omega total = .83) and test-retest consistency (ICC = .92 at 2.7 years). The strongest convergent correlations were with general cognition and executive functioning, while discriminant validity was demonstrated with its weakest and negative correlations being with BPS. There was strong classification accuracy in distinguishing MCI from normal cognition (AUC = .79; optimal cutoff point < 18), and mild-to-moderate dementia from MCI (AUC = .85; optimal cutoff point < 13). Furthermore, the MoCA-22 had negligible-to-small differences among those with and without vision limitations. Conclusions: These findings add to the evidence of the MoCA-22's utility and it serves as a useful cognitive screening tool with sound reliability and validity.

Heart rate and breathing effects on attention and memory (HeartBEAM): study protocol for a randomized controlled trial in older adults

BACKGROUND

In healthy people, the "fight-or-flight" sympathetic system is counterbalanced by the "rest-and-digest" parasympathetic system. As we grow older, the parasympathetic system declines as the sympathetic system becomes hyperactive. In our prior heart rate variability biofeedback and emotion regulation (HRV-ER) clinical trial, we found that increasing parasympathetic activity through daily practice of slow-paced breathing significantly decreased plasma amyloid-β (Aβ) in healthy younger and older adults. In healthy adults, higher plasma Aβ is associated with greater risk of Alzheimer's disease (AD). Our primary goal of this trial is to reproduce and extend our initial findings regarding effects of slow-paced breathing on Aβ. Our secondary objectives are to examine the effects of daily slow-paced breathing on brain structure and the rate of learning.

METHODS

Adults aged 50-70 have been randomized to practice one of two breathing protocols twice daily for 9 weeks: (1) "slow-paced breathing condition" involving daily cognitive training followed by slow-paced breathing designed to maximize heart rate oscillations or (2) "random-paced breathing condition" involving daily cognitive training followed by random-paced breathing to avoid increasing heart rate oscillations. The primary outcomes are plasma Aβ40 and Aβ42 levels and plasma Aβ42/40 ratio. The secondary outcomes are brain perivascular space volume, hippocampal volume, and learning rates measured by cognitive training performance. Other pre-registered outcomes include plasma pTau-181/tTau ratio and urine Aβ42. Recruitment began in January 2023. Interventions are ongoing and will be completed by the end of 2023.

DISCUSSION

Our HRV-ER trial was groundbreaking in demonstrating that a behavioral intervention can reduce plasma Aβ levels relative to a randomized control group. We aim to reproduce these findings while testing effects on brain clearance pathways and cognition.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05602220. Registered on January 12, 2023.

Digital Methods for Performing Daily Tasks Among Older Adults: An Initial Report of Frequency of Use and Perceived Utility

OBJECTIVE

Digital technologies permit new ways of performing instrumental activities of daily living (iADLs) for older adults, but these approaches are not usually considered in existing iADL measures. The current study investigated how a sample of older adults report using digital versus analog approaches for iADLs.

METHOD

248 older adults completed the Digital and Analog Daily Activities Survey, a newly developed measure of how an individual performs financial, navigation, medication, and other iADLs.

RESULTS

The majority of participants reported regularly using digital methods for some iADLs, such as paying bills (67.7%) and using GPS (67.7%). Low digital adopters were older than high adopters (F(2, 245) = 12.24, p < .001), but otherwise the groups did not differ in terms of gender, years of education, or history of neurological disorders. Participants who used digital methods relatively more than analog methods reported greater levels of satisfaction with their approach and fewer daily errors.

CONCLUSIONS

Many older adults have adopted digital technologies for supporting daily tasks, which suggests limitations to the validity of current iADL assessments. By capitalizing on existing habits and enriching environments with new technologies, there are opportunities to promote technological reserve in older adults in a manner that sustains daily functioning.

Brain Health Registry Study Partner Portal: Novel infrastructure for digital, dyadic data collection

BACKGROUND

In Alzheimer's disease (AD) research, subjective reports of cognitive and functional decline from participant-study partner dyads is an efficient method of assessing cognitive impairment and clinical progression.

METHODS

Demographics and subjective cognitive/functional decline (Everyday Cognition Scale [ECog]) scores from dyads enrolled in the Brain Health Registry (BHR) Study Partner Portal were analyzed. Associations between dyad characteristics and both ECog scores and study engagement were investigated.

RESULTS

A total of 10,494 BHR participants (mean age = 66.9 ± 12.16 standard deviations, 67.4% female) have enrolled study partners (mean age = 64.3 ± 14.3 standard deviations, 49.3% female), including 8987 dyads with a participant 55 years of age or older. Older and more educated study partners were more likely to complete tasks and return for follow-up. Twenty-five percent to 27% of older adult participants had self and study partner-report ECog scores indicating a possible cognitive impairment.

DISCUSSION

The BHR Study Partner Portal is a unique digital tool for capturing dyadic data, with high impact applications in the clinical neuroscience and AD fields. Highlights The Brain Health Registry (BHR) Study Partner Portal is a novel, digital platform of >10,000 dyads. Collection of dyadic online subjective cognitive and functional data is feasible. The portal has good usability as evidenced by positive study partner feedback. The portal is a potential scalable strategy for cognitive impairment screening in older adults.

An explainable machine learning approach for Alzheimer's disease classification

The early diagnosis of Alzheimer's disease (AD) presents a significant challenge due to the subtle biomarker changes often overlooked. Machine learning (ML) models offer a promising tool for identifying individuals at risk of AD. However, current research tends to prioritize ML accuracy while neglecting the crucial aspect of model explainability. The diverse nature of AD data and the limited dataset size introduce additional challenges, primarily related to high dimensionality. In this study, we leveraged a dataset obtained from the National Alzheimer's Coordinating Center, comprising 169,408 records and 1024 features. After applying various steps to reduce the feature space. Notably, support vector machine (SVM) models trained on the selected features exhibited high performance when tested on an external dataset. SVM achieved a high F1 score of 98.9% for binary classification (distinguishing between NC and AD) and 90.7% for multiclass classification. Furthermore, SVM was able to predict AD progression over a 4-year period, with F1 scores reached 88% for binary task and 72.8% for multiclass task. To enhance model explainability, we employed two rule-extraction approaches: class rule mining and stable and interpretable rule set for classification model. These approaches generated human-understandable rules to assist domain experts in comprehending the key factors involved in AD development. We further validated these rules using SHAP and LIME models, underscoring the significance of factors such as MEMORY, JUDGMENT, COMMUN, and ORIENT in determining AD risk. Our experimental outcomes also shed light on the crucial role of the Clinical Dementia Rating tool in predicting AD.

Digital Clock and Recall is superior to the Mini-Mental State Examination for the detection of mild cognitive impairment and mild dementia

BACKGROUND

Disease-modifying treatments for Alzheimer's disease highlight the need for early detection of cognitive decline. However, at present, most primary care providers do not perform routine cognitive testing, in part due to a lack of access to practical cognitive assessments, as well as time and resources to administer and interpret the tests. Brief and sensitive digital cognitive assessments, such as the Digital Clock and Recall (DCR™), have the potential to address this need. Here, we examine the advantages of DCR over the Mini-Mental State Examination (MMSE) in detecting mild cognitive impairment (MCI) and mild dementia.

METHODS

We studied 706 participants from the multisite Bio-Hermes study (age mean ± SD = 71.5 ± 6.7; 58.9% female; years of education mean ± SD = 15.4 ± 2.7; primary language English), classified as cognitively unimpaired (CU; n = 360), mild cognitive impairment (MCI; n = 234), or probable mild Alzheimer's dementia (pAD; n = 111) based on a review of medical history with selected cognitive and imaging tests. We evaluated cognitive classifications (MCI and early dementia) based on the DCR and the MMSE against cohorts based on the results of the Rey Auditory Verbal Learning Test (RAVLT), the Trail Making Test-Part B (TMT-B), and the Functional Activities Questionnaire (FAQ). We also compared the influence of demographic variables such as race (White vs. Non-White), ethnicity (Hispanic vs. Non-Hispanic), and level of education (≥ 15 years vs. < 15 years) on the DCR and MMSE scores.

RESULTS

The DCR was superior on average to the MMSE in classifying mild cognitive impairment and early dementia, AUC = 0.70 for the DCR vs. 0.63 for the MMSE. DCR administration was also significantly faster (completed in less than 3 min regardless of cognitive status and age). Among 104 individuals who were labeled as "cognitively unimpaired" by the MMSE (score ≥ 28) but actually had verbal memory impairment as confirmed by the RAVLT, the DCR identified 84 (80.7%) as impaired. Moreover, the DCR score was significantly less biased by ethnicity than the MMSE, with no significant difference in the DCR score between Hispanic and non-Hispanic individuals.

CONCLUSIONS

DCR outperforms the MMSE in detecting and classifying cognitive impairment-in a fraction of the time-while being not influenced by a patient's ethnicity. The results support the utility of DCR as a sensitive and efficient cognitive assessment in primary care settings.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04733989.

Ecological validity of cognitive fluctuations in dementia with Lewy bodies

OBJECTIVES

Cognitive fluctuations are a core clinical feature of dementia with Lewy bodies (DLB), but their contribution to the everyday functioning difficulties evident DLB are not well understood. The current study evaluated whether intraindividual variability across a battery of neurocognitive tests (intraindividual variability-dispersion) and daily cognitive fluctuations as measured by informant report are associated with worse daily functioning in DLB.

METHODS

The study sample included 97 participants with consensus-defined DLB from the National Alzheimer's Coordinating Center (NACC). Intraindividual variability-dispersion was measured using the coefficient of variation, which divides the standard deviation of an individual's performance scores across 12 normed neurocognitive indices from the NACC neuropsychological battery by that individual's performance mean. Informants reported on daily cognitive fluctuations using the Mayo Fluctuations Scale (MFS) and on daily functioning using the functional activities questionnaire (FAQ).

RESULTS

Logistic regression identified a large univariate association of intraindividual variability-dispersion and presence of daily cognitive fluctuations on the MFS (Odds Ratio = 73.27, 95% Confidence Interval = 1.38, 3,895.05). Multiple linear regression demonstrated that higher intraindividual variability-dispersion and presence of daily cognitive fluctuations as assessed by the MFS were significantly and independently related to worse daily functioning (FAQ scores).

CONCLUSIONS

Among those with DLB, informant-rated daily cognitive fluctuations and cognitive fluctuations measured in the clinic (as indexed by intraindividual variability-dispersion across a battery of tests) were independently associated with poorer everyday functioning. These data demonstrate ecological validity in measures of cognitive fluctuations in DLB.

Predicting Conversion Time from Mild Cognitive Impairment to Dementia with Interval-Censored Models

Background

Mild cognitive impairment (MCI) patients are at a high risk of developing Alzheimer's disease and related dementias (ADRD) at an estimated annual rate above 10%. It is clinically and practically important to accurately predict MCI-to-dementia conversion time.

Objective

It is clinically and practically important to accurately predict MCI-to-dementia conversion time by using easily available clinical data.

Methods

The dementia diagnosis often falls between two clinical visits, and such survival outcome is known as interval-censored data. We utilized the semi-parametric model and the random forest model for interval-censored data in conjunction with a variable selection approach to select important measures for predicting the conversion time from MCI to dementia. Two large AD cohort data sets were used to build, validate, and test the predictive model.

Results

We found that the semi-parametric model can improve the prediction of the conversion time for patients with MCI-to-dementia conversion, and it also has good predictive performance for all patients.

Conclusions

Interval-censored data should be analyzed by using the models that were developed for interval- censored data to improve the model performance.

Effect of hyperbaric oxygen on symptoms of dementia in patients with delayed encephalopathy after acute carbon monoxide poisoning

OBJECTIVES

Delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) is the most severe complication of carbon monoxide poisoning, which seriously endangers patients' quality of life. This study aims to investigate the efficacy of hyperbaric oxygen (HBO2) on improving dementia symptoms in patients with DEACMP.

METHODS

A retrospective analysis was performed on DEACMP patients, who visited Xiangya Hospital, Central South University from June 2014 to June 2020. Among them, patients who received conventional drug treatment combined with HBO2 treatment were included in an HBO2 group, while those who only received conventional drug treatment were included in a control group. HBO2 was administered once daily. Patients in the HBO2 group received 6 courses of treatment, with each course consisting of 10 sessions. The Hasegawa Dementia Scale (HDS) was used to diagnose dementia, and the Clinical Dementia Rating (CDR) was used to grade the severity of dementia for DEACMP. The Alzheimer's Disease Assessment Scale-Cognitive Section (ADAS-Cog), the Functional Activities Questionnaire (FAQ), the Neuropsychiatric Inventory (NPI), and the Clinician's Interview-Based Impression of Change-Plus Caregiver Input (CIBIC-Plus) were performed to assess cognitive function, ability to perform activities of daily living (ADL), behavioral and psychological symptoms, and overall function. The study further analyzed the results of objective examinations related to patients' dementia symptoms, including magnetic resonance imaging detection of white matter lesions and abnormal electroencephalogram (EEG). The changes of the above indicators before and after treatment, as well as the differences between the 2 groups after treatment were compared.

RESULTS

There was no significant difference in the HDS score and CDR grading between the 2 groups before treatment (both P>0.05). After treatment, the score of ADAS-Cog, FAQ, NPI, and CIBIC Plus grading of the 2 groups were significantly improved, and the improvement of the above indicators in the HBO2 group was greater than that in the control group (all P<0.05). The effective rate of the HBO2 group in treating DEACMP was significantly higher than that of the control group (89.47% vs 65.87%, P<0.05). The objective examination results (white matter lesions and abnormal EEG) showed that the recovery of patients in the HBO2 group was better than that in the control group.

CONCLUSIONS

Hyperbaric oxygen can significantly relieve the symptoms of dementia in patients with DEACMP.

Informant Characteristics Influence Reports of Participant Functioning and their Associations with Neuropsychological Performance in Non-Hispanic Black Adults

OBJECTIVE

Assessing one's functional capacity-in addition to neuropsychological performance-is essential for determining neurocognitive status, and functional assessment is often provided via informant report. Although informant characteristics have been shown to influence reports of participant functioning, the degree to which they moderate relationships between reported functioning and participant performance on neuropsychological testing is unclear. Moreover, associations among informant characteristics, reported functioning, and neuropsychological performance have not been adequately examined with non-Hispanic Black (NHB) samples, despite this population's disproportionately high risk of Alzheimer's disease and related dementias.

METHOD

In this cross-sectional observational study, we examined the influence of informant characteristics on informant reports of participant functioning (assessed via the Functional Activities Questionnaire [FAQ]) and associations between reported functioning and participant performance on neuropsychological testing, among NHB adult participants in the National Alzheimer's Coordinating Center cohort (n = 1024).

RESULTS

Informants who were younger, female, more educated, knew participants longer, or lived with participants reported poorer participant functioning (p < .001). However, younger (vs. older) informants provided reports of functioning that were more predictive of visuoconstructional ability and visual memory, and male (vs. female) informants provided reports of functioning that were more predictive of verbal memory, visuoconstructional ability and visual memory, and language (ps < .001).

CONCLUSIONS

Within the context of neurocognitive evaluations of NHB participants, informant characteristics may influence subjective reports of participants' functioning and the extent to which reported functioning corroborates objective participant performance on neuropsychological testing.

Alterations of gut microbiota are associated with brain structural changes in the spectrum of Alzheimer's disease: the SILCODE study in Hainan cohort

Background

The correlation between gut microbiota and Alzheimer's disease (AD) is increasingly being recognized by clinicians. However, knowledge about the gut-brain-cognition interaction remains largely unknown.

Methods

One hundred and twenty-seven participants, including 35 normal controls (NCs), 62 with subjective cognitive decline (SCD), and 30 with cognitive impairment (CI), were included in this study. The participants underwent neuropsychological assessments and fecal microbiota analysis through 16S ribosomal RNA (rRNA) Illumina Miseq sequencing technique. Structural MRI data were analyzed for cortical anatomical features, including thickness, sulcus depth, fractal dimension, and Toro's gyrification index using the SBM method. The association of altered gut microbiota among the three groups with structural MRI metrics and cognitive function was evaluated. Furthermore, co-expression network analysis was conducted to investigate the gut-brain-cognition interactions.

Results

The abundance of Lachnospiraceae, Lachnospiracea_incertae_sedis, Fusicatenibacter, and Anaerobutyricum decreased with cognitive ability. Rikenellaceae, Odoribacteraceae, and Alistipes were specifically enriched in the CI group. Mediterraneibacter abundance was correlated with changes in brain gray matter and cerebrospinal fluid volume (p = 0.0214, p = 0.0162) and significantly with changes in cortical structures in brain regions, such as the internal olfactory area and the parahippocampal gyrus. The three colonies enriched in the CI group were positively correlated with cognitive function and significantly associated with changes in cortical structure related to cognitive function, such as the precuneus and syrinx gyrus.

Conclusion

This study provided evidence that there was an inner relationship among the altered gut microbiota, brain atrophy, and cognitive decline. Targeting the gut microbiota may be a novel therapeutic strategy for early AD.

Regional cerebral tau predicts decline in everyday functioning across the Alzheimer's disease spectrum

BACKGROUND

Emerging difficulty performing cognitively complex everyday tasks, or 'instrumental activities of daily living' (IADL) may be an early clinical sign of Alzheimer's disease (AD). We aimed to investigate how changes over time in everyday functioning relate to cerebral tau burden across the AD clinical spectrum.

METHODS

We included 581 participants (73.9 ± 7.6 years old; 52% female) from the Alzheimer's Disease Neuroimaging Initiative who underwent tau positron emission tomography (PET) and completed at least two assessments of the Functional Activities Questionnaire (FAQ). Participants were classified as cognitively normal (n = 334) or symptomatic (n = 247). We analyzed the association between longitudinal FAQ scores and baseline tau in six temporal, parietal, and frontal brain regions in mixed-effects models. Models were run in the entire sample, as well as stratified by diagnostic group (cognitively normal or symptomatic). We additionally investigated tau-PET adjusted for, as well as interacting with, amyloid-β.

RESULTS

Greater tau burden in several frontal, temporal, and parietal regions was associated with steeper decline over time in everyday functioning. These findings remained when adjusting for baseline global cortical amyloid-β; amyloid-β itself was only associated with change over time in FAQ scores when tau was not included in the model. When stratifying by diagnostic group, most associations between tau and everyday functioning, adjusted for amyloid-β, were present only in the symptomatic group.

CONCLUSIONS

The rate of change in everyday functioning is related to baseline tau burden in various brain regions, more strongly so than global cortical amyloid-β, specifically in cognitively symptomatic individuals. Longitudinal studies in incident dementia populations are needed to better understand functional changes in response to AD pathology across the disease.

Clinical observation and mechanism of acupuncture on amnestic mild cognitive impairment based on the gut-brain axis: study protocol for a randomized controlled trial

Background

Amnestic mild cognitive impairment (aMCI) is a pre-dementia condition associated with declined cognitive function dominated by memory impairment. The occurrence of aMCI is associated with the gut-brain axis. Previous studies have shown cognitive improvements in MCI after acupuncture treatment. This study evaluates whether acupuncture can produce a therapeutic effect in patients with aMCI by modulating the gut-brain axis.

Methods and design

This is a prospective, parallel, multicenter randomized controlled trial. A total of 40 patients with aMCI will be randomly assigned to an acupuncture group (AG) or a waiting-list group (WG), participants in both groups will receive health education on improving cognitive function at each visit, and acupuncture will be conducted twice a week for 12 weeks in the AG. Another 20 matched healthy volunteers will be enrolled as normal control. The primary outcome will be the change in Alzheimer's Disease Assessment Scale-cognitive scale score before and after treatment. Additionally, functional magnetic resonance imaging data, faeces, and blood will be collected from each participant to characterize the brain function, gut microbiota, and inflammatory cytokines, respectively. The differences between patients with aMCI and healthy participants, and the changes in the AG and WG groups before and after treatment will be observed. Ultimately, the correlation among brain function, gut microbiota, inflammatory cytokines, and clinical efficacy evaluation in patients with aMCI will be analyzed.

Discussion

This study will identify the efficacy and provide preliminary data on the possible mechanism of acupuncture in treating aMCI. Furthermore, it will also identify biomarkers of the gut microbiota, inflammatory cytokines, and brain function correlated with therapeutic effects. The results of this study will be published in peer-reviewed journals.

Clinical trial registration

http://www.chictr.org.cn, identifier ChiCTR2200062084.

Delivering Food Resources and Kitchen Skills (FoRKS) to Adults with Food Insecurity and Hypertension: A Pilot Study

Food insecurity affects nearly 50 million Americans and is linked to cardiovascular disease risk factors and health disparities. The purpose of this single-arm pilot study was to determine the feasibility of a 16-week dietitian-led lifestyle intervention to concurrently address food access, nutrition literacy, cooking skills, and hypertension among safety-net primary care adult patients. The Food Resources and Kitchen Skills (FoRKS) intervention provided nutrition education and support for hypertension self-management, group kitchen skills and cooking classes from a health center teaching kitchen, medically tailored home-delivered meals and meal kits, and a kitchen toolkit. Feasibility and process measures included class attendance rates and satisfaction and social support and self-efficacy toward healthy food behaviors. Outcome measures included food security, blood pressure, diet quality, and weight. Participants (n = 13) were on average {mean (SD)} aged 58.9 ± 4.5 years, 10 were female, and 12 were Black or African American. Attendance averaged 19 of 22 (87.1%) classes and satisfaction was rated as high. Food self-efficacy and food security improved, and blood pressure and weight declined. FoRKS is a promising intervention that warrants further evaluation for its potential to reduce cardiovascular disease risk factors among adults with food insecurity and hypertension.

Brief Report: An Evaluation of Item Bias on the Functional Activities Questionnaire

OBJECTIVE

To evaluate whether the Functional Activities Questionnaire (FAQ), a commonly used measure of functional status in neurodegenerative disease research, performs equivalently across demographically diverse subgroups of participants.

METHOD

The FAQs from 30,613 National Alzheimer's Coordinating Center participants were evaluated with a hybrid graded response model-logistic ordinal regression approach to determine the presence of differential item functioning (DIF) within five demographic groups: education, ethnicity, race, language, and sex.

RESULTS

Measurable DIF was observed for FAQ items in all groups; however, measures of effect size, latent trait distributions, and item characteristic curves suggested that the impact was minimal for research and practice.

CONCLUSIONS

The FAQ is able to provide minimally biased assessments of daily functioning across diverse participants, suggesting potential value for offsetting disparities in diagnosis and treatment.

Intra-individual variability in cognitive performance predicts functional decline in Parkinson's disease

BACKGROUND

Cognitive deficits contribute to disability in Parkinson's disease (PD). Cognitive intra-individual variability (IIV) is associated with cognitive decline in age-related disorders, but IIV has not been related to functional ability in PD. We examined IIV in predicting functional ability in participants with PD.

METHODS

De-identified National Alzheimer's Coordinating Center data (N = 1,228) from baseline and follow-up visits included participants with PD propensity score matched to control participants at baseline on age (M = 72), education (M = 15), and gender (28% female). PD symptom duration averaged 6 years. Outcome measures included the Functional Ability Questionnaire (FAQ), overall test battery mean (OTBM) of ten cognitive variables, IIV calculated as the standard deviation of cognitive data for each participant, Geriatric Depression Scale (GDS), and Unified PD Rating Scale gait and posture items. Baseline FAQ status in the PD group was predicted using logistic regression with age, education, cognition, GDS, and motor function as predictors. We compared baseline characteristics of PD participants with and without functional impairment at follow up.

RESULTS

PD participants showed lower OTBM and greater IIV, GDS, and motor dysfunction than controls (p < .0001). Education, OTBM, IIV, GDS, and gait predicted functional status (77% overall classification; AUC = .84). PD participants with functional impairment at follow up showed significantly lower OTBM and greater IIV, GDS, and motor dysfunction at baseline (p < .001).

CONCLUSION

IIV independently predicts functional status in participants with PD while controlling for other variables. PD participants with functional impairment at follow up showed greater IIV than those without functional impairment at follow up.

Cerebrospinal Fluid Complement 4 Levels Were Associated with Alzheimer's Disease Pathology and Cognition in Non-Demented Elderly

BACKGROUND

Numerous studies have shown that the complement system plays an important role in Alzheimer's disease (AD). However, whether complement 4 (C4) protein in cerebrospinal fluid (CSF) was associated with AD pathology, especially in the early stage of AD, is still unclear.

OBJECTIVE

We aimed to explore the association of CSF C4 with AD pathology and cognition in the preclinical AD.

METHODS

The study included a total of 287 participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Based on the A/T scheme, they were divided into four groups to access the changes of CSF C4 in the preclinical AD. Linear regression models were used to test the associations between CSF C4 and AD core biomarkers, namely Aβ42, P-tau, and T-tau.

RESULTS

The level of CSF C4 decreased in the A + T- group compared with the A-T- group (p = 0.04) and it increased in the A-T+ group compared to the A + T- group (p = 0.01). In pooled samples, C4 was significantly associated with AD core biomarkers (all p < 0.05), but only in the A + group after stratification according to the A/T scheme. Furthermore, CSF C4 levels at baseline were associated with longitudinal cognitive changes.

CONCLUSIONS

Our results showed that CSF C4 levels changed dynamically in the preclinical AD, and that the responses of CSF C4 to brain Aβ pathology, tau pathology and neurodegeneration were found only in the presence of amyloid plaques, both of which indicates the complex link between C4 and AD.

Prediction of Medical Conditions Using Machine Learning Approaches: Alzheimer’s Case Study

Alzheimer’s Disease (AD) is a highly prevalent condition and most of the people suffering from it receive the diagnosis late in the process. The diagnosis is currently established following an evaluation of the protein biomarkers in cerebrospinal fluid (CSF), brain imaging, cognitive tests, and the medical history of the individuals. While diagnostic tools based on CSF collections are invasive, the tools used for acquiring brain scans are expensive. Taking these into account, an early predictive system, based on Artificial Intelligence (AI) approaches, targeting the diagnosis of this condition, as well as the identification of lead biomarkers becomes an important research direction. In this survey, we review the state-of-the-art research on machine learning (ML) techniques used for the detection of AD and Mild Cognitive Impairment (MCI). We attempt to identify the most accurate and efficient diagnostic approaches, which employ ML techniques and therefore, the ones most suitable to be used in practice. Research is still ongoing to determine the best biomarkers for the task of AD classification. At the beginning of this survey, after an introductory part, we enumerate several available resources, which can be used to build ML models targeting the diagnosis and classification of AD, as well as their main characteristics. After that, we discuss the candidate markers which were used to build AI models with the best results in terms of diagnostic accuracy, as well as their limitations.

Toward Pre-Diagnostic Detection of Dementia in Primary Care

Background: Preventing dementia warrants the pragmatic engagement of primary care. Objective: This study predicted conversion to dementia 12 months before diagnosis with indicators that primary care can utilize within the practical constraints of routine practice. Methods: The study analyzed data from the Alzheimer’s Disease Neuroimaging Initiative (Total sample = 645, converting participants = 54). It predicted the conversion from biological (plasma neurofilament light chain), cognitive (Trails Making Test– B), and functional (Functional Activities Questionnaire) measures, in addition to demographic variables (age and education). Results: A Gradient Booster Trees classifier effectively predicted the conversion, based on a Synthetic Minority Oversampling Technique (n = 1,290, F1 Score = 92, AUC = 94, Recall = 87, Precision = 97, Accuracy = 92). Subsequent analysis indicated that the MCI False Positive group (i.e., non-converting participants with cognitive impairment flagged by the model for prospective conversion) scored significantly lower on multiple cognitive tests (Montreal Cognitive Assessment, p < 0.002; ADAS-13, p < 0.0004; Rey Auditory Verbal Learning Test, p < 0.002/0.003) than the MCI True Negative group (i.e., correctly classified non-converting participants with cognitive impairment). These groups also differed in CSF tau levels (p < 0.04), while consistent effect size differences emerged in the all-pairwise comparisons of hippocampal volume and CSF Aβ1 - 42. Conclusion: The model effectively predicted 12-month conversion to dementia and further identified non-converting participants with MCI, in the False Positive group, at relatively higher neurocognitive risk. Future studies may seek to extend these results to earlier prodromal phases. Detection of dementia before diagnosis may be feasible and practical in primary care settings, pending replication of these findings in diverse clinical samples.

Cognitive screening with functional assessment improves diagnostic accuracy and attenuates bias

INTRODUCTION

Cognitive screening measures often lack sensitivity and are hampered by inequities across ethnoracial groups. A multitrait multimethod (MTMM) classification may attenuate these shortcomings.

METHODS

A sample of 7227 participants across the diagnostic spectrum were selected from the National Alzheimer's Coordinating Center cohort. Random forest ensemble methods were used to predict diagnosis across the sample and within Black American (n = 1025) and non-Hispanic White groups (n = 5263) based on: (1) a demographically corrected Montreal Cognitive Assessment (MoCA), (2) MoCA and Functional Assessment Questionnaire (FAQ), (3) MoCA and FAQ with demographic correction.

RESULTS

The MTMM approach with demographic correction had the highest diagnostic accuracy for the cognitively unimpaired (area under curve [AUC] [95% confidence interval (CI)]): 0.906 [0.892, 0.920]) and mild cognitive impairment (AUC: 0.835 [0.810, 0.860]) groups and reduced racial disparities.

DISCUSSION

With further validation, the MTMM approach combining cognitive screening and functional status assessment may serve to improve diagnostic accuracy and extend opportunities for early intervention with greater equity.

Instrumental Activities of Daily Living Scales to Detect Cognitive Impairment and Dementia in Low- and Middle-Income Countries: A Systematic Review

BACKGROUND

The largest proportion of people with dementia worldwide live in low- and middle- income countries (LMICs), with dementia prevalence continuing to rise. Assessment and diagnosis of dementia involves identifying the impact of cognitive decline on function, usually measured by instrumental activities of daily living (IADLs).

OBJECTIVE

This review aimed to identify IADL measures which are specifically developed, validated, or adapted for use in LMICs to guide selection of such tools.

METHODS

A systematic search was conducted (fourteen databases) up to April 2020. Only studies reporting on development, validation, or adaptation of IADL measures for dementia or cognitive impairment among older adults (aged over 50) in LMICs were included. The QUADAS 2 was used to assess quality of diagnostic accuracy studies.

RESULTS

22 papers met inclusion criteria; identifying 19 discrete IADL tools across 11 LMICs. These were either translated from IADL measures used in high-income countries (n = 6), translated and adapted for cultural differences (n = 6), or newly developed for target LMIC populations (n = 7). Seven measures were investigated in multiple studies; overall quality of diagnostic accuracy was moderate to good.

CONCLUSION

Reliability, validity, and accuracy of IADL measures for supporting dementia diagnosis within LMICs was reported. Key components to consider when selecting an IADL tool for such settings were highlighted, including choosing culturally appropriate, time-efficient tools that account for gender- and literacy-bias, and can be conducted by any volunteer with appropriate training. There is a need for greater technical and external validation of IADL tools across different regions, countries, populations, and cultures.