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1.
Front Digit Health ; 6: 1366176, 2024.
Article in English | MEDLINE | ID: mdl-38707195

ABSTRACT

Accurate balance assessment is important in healthcare for identifying and managing conditions affecting stability and coordination. It plays a key role in preventing falls, understanding movement disorders, and designing appropriate therapeutic interventions across various age groups and medical conditions. However, traditional balance assessment methods often suffer from subjectivity, lack of comprehensive balance assessments and remote assessment capabilities, and reliance on specialized equipment and expert analysis. In response to these challenges, our study introduces an innovative approach for estimating scores on the Modified Clinical Test of Sensory Interaction on Balance (m-CTSIB). Utilizing wearable sensors and advanced machine learning algorithms, we offer an objective, accessible, and efficient method for balance assessment. We collected comprehensive movement data from 34 participants under four different sensory conditions using an array of inertial measurement unit (IMU) sensors coupled with a specialized system to evaluate ground truth m-CTSIB balance scores for our analysis. This data was then preprocessed, and an extensive array of features was extracted for analysis. To estimate the m-CTSIB scores, we applied Multiple Linear Regression (MLR), Support Vector Regression (SVR), and XGBOOST algorithms. Our subject-wise Leave-One-Out and 5-Fold cross-validation analysis demonstrated high accuracy and a strong correlation with ground truth balance scores, validating the effectiveness and reliability of our approach. Key insights were gained regarding the significance of specific movements, feature selection, and sensor placement in balance estimation. Notably, the XGBOOST model, utilizing the lumbar sensor data, achieved outstanding results in both methods, with Leave-One-Out cross-validation showing a correlation of 0.96 and a Mean Absolute Error (MAE) of 0.23 and 5-fold cross-validation showing comparable results with a correlation of 0.92 and an MAE of 0.23, confirming the model's consistent performance. This finding underlines the potential of our method to revolutionize balance assessment practices, particularly in settings where traditional methods are impractical or inaccessible.

2.
J Alzheimers Dis Rep ; 8(1): 637-646, 2024.
Article in English | MEDLINE | ID: mdl-38746641

ABSTRACT

Background: Few studies have investigated associations between perceived social determinants of health (SDOH) and Alzheimer's disease and related dementia (ADRD) biomarkers or between SDOH and resilience against ADRD. Objective: To examine associations between perceived and objective SDOH and ADRD-related outcomes. Methods: We used cross-sectional data on≥50-year-olds without dementia in the Healthy Brain Initiative (n = 162). Questionnaires captured trust in neighbors and indices of perceived neighborhood greenspace access, time spent in neighborhood greenspaces, and interpersonal discrimination. Residential addresses were linked to 2021 Area Deprivation Index scores. The Vulnerability Index (VI) is based on 12 dementia risk factors (e.g., age, race/ethnicity, diabetes) and Resilience Index (RI) is based on 6 protective factors (e.g., diet, mindfulness, physical activity). Cognitive measured included number symbol coding task and Montreal Cognitive Assessment. Biomarkers included Aß42/40 and pTau-217/npTau-217, hippocampal and white matter hyperintensity volume, lipoprotein A, and high-sensitivity c-reactive protein. Results: Perceived greater access to greenspaces (estimate = 2.83, 95% CI = 1.40-4.26) and greater time in neighborhood greenspaces were associated with greater RI scores (estimate = 2.30, 95% CI = 1.24-3.35). Reporting greater discrimination (estimate = 0.10, 95% CI = 0.04-0.16) and living in higher deprivation neighborhoods were associated with greater VI scores (estimate = 0.017, 95% CI = 0.003-0.032). Greater discrimination was associated with greater white matter hyperintensity volume (estimate = 0.27, 95% CI = 0.04-0.51). Conclusions: Perceived greenspace access and time spent in greenspaces were associated with resilience against ADRD, and interpersonal discrimination was associated with vulnerability to ADRD. Future work needs to validate perceived SDOH measures, examine associations in racially/ethnic diverse populations, and investigate longitudinal associations between SDOH and ADRD-related biomarkers.

3.
J Alzheimers Dis ; 98(3): 1017-1027, 2024.
Article in English | MEDLINE | ID: mdl-38489189

ABSTRACT

Background: Lifestyle factors are linked to differences in brain aging and risk for Alzheimer's disease, underscored by concepts like 'cognitive reserve' and 'brain maintenance'. The Resilience Index (RI), a composite of 6 factors (cognitive reserve, physical and cognitive activities, social engagement, diet, and mindfulness) provides such a holistic measure. Objective: This study aims to examine the association of RI scores with cognitive function and assess the mediating role of cortical atrophy. Methods: Baseline data from 113 participants (aged 45+, 68% female) from the Healthy Brain Initiative were included. Life course resilience was estimated with the RI, cognitive performance with Cognivue®, and brain health using a machine learning derived Cortical Atrophy Score (CAS). Mediation analysis probed the relationship between RI, cognitive outcomes, and cortical atrophy. Results: In age and sex adjusted models, the RI was significantly associated with CAS (ß= -0.25, p = 0.006) and Cognivue® scores (ß= 0.32, p < 0.001). The RI-Cognivue® association was partially mediated by CAS (ß= 0.07; 95% CI [0.02, 0.14]). Conclusions: Findings revealed that the collective effect of early and late-life lifestyle resilience factors on cognition are partially explained by their association with less brain atrophy. These findings underscore the value of comprehensive lifestyle assessments in understanding the risk and progression of cognitive decline and Alzheimer's disease in an aging population.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Resilience, Psychological , Humans , Female , Aged , Male , Alzheimer Disease/pathology , Magnetic Resonance Imaging , Neuropsychological Tests , Brain/diagnostic imaging , Brain/pathology , Cognition , Cognitive Dysfunction/psychology , Atrophy/pathology
4.
Expert Opin Emerg Drugs ; 28(3): 167-180, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37531299

ABSTRACT

INTRODUCTION: Despite faster cognitive decline and greater negative impact on patients and family caregivers, drug development efforts in Dementia with Lewy Bodies (DLB) fall behind those for Alzheimer's Disease (AD). Current off-label drug DLB treatment options are limited to symptomatic agents developed to address cognitive deficits in AD, motor deficits in Parkinson's Disease, or behavioral symptoms in psychiatric disease. Aided by recent improvements in DLB diagnosis, a new focus on the development of disease-modifying agents (DMA) is emerging. AREAS COVERED: Driven by evidence supporting different pathological mechanisms in DLB and PDD, this review assesses the evidence on symptomatic drug treatments and describes current efforts in DMA development in DLB. Specifically, our goals were to: (1) review evidence supporting the use of symptomatic drug treatments in DLB; (2) review the current DMA pipeline in DLB with a focus on Phase II and III clinical trials; and (3) identify potential issues with the development of DMA in DLB. Included in this review were completed and ongoing drug clinical trials in DLB registered on ClinicalTrials.gov (no time limits set for the search) or disseminated at the 2023 international conference on Clinical Trials in AD. Drug clinical trials registered in non-US clinical trial registries were not included. EXPERT OPINION: Adoption of current symptomatic drug treatments used off-label in DLB relied on efficacy of benefits in other disorders rather than evidence from randomized controlled clinical trials. Symptoms remain difficult to manage. Several DMA drugs are currently being evaluated as either repurposing candidates or novel small molecules. Continued improvement in methodological aspects including development of DLB-specific outcome measures and biomarkers is needed to move the field of DMA drug development forward.

5.
Alzheimers Dement ; 19(9): 4204-4225, 2023 09.
Article in English | MEDLINE | ID: mdl-37218539

ABSTRACT

INTRODUCTION: Individuals living in rural communities are at heightened risk for Alzheimer's disease and related dementias (ADRD), which parallels other persistent place-based health disparities. Identifying multiple potentially modifiable risk factors specific to rural areas that contribute to ADRD is an essential first step in understanding the complex interplay between various barriers and facilitators. METHODS: An interdisciplinary, international group of ADRD researchers convened to address the overarching question of: "What can be done to begin minimizing the rural health disparities that contribute uniquely to ADRD?" In this state of the science appraisal, we explore what is known about the biological, behavioral, sociocultural, and environmental influences on ADRD disparities in rural settings. RESULTS: A range of individual, interpersonal, and community factors were identified, including strengths of rural residents in facilitating healthy aging lifestyle interventions. DISCUSSION: A location dynamics model and ADRD-focused future directions are offered for guiding rural practitioners, researchers, and policymakers in mitigating rural disparities. HIGHLIGHTS: Rural residents face heightened Alzheimer's disease and related dementia (ADRD) risks and burdens due to health disparities. Defining the unique rural barriers and facilitators to cognitive health yields insight. The strengths and resilience of rural residents can mitigate ADRD-related challenges. A novel "location dynamics" model guides assessment of rural-specific ADRD issues.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/epidemiology , Rural Population , Rural Health , Risk Factors
6.
J Alzheimers Dis Rep ; 7(1): 151-164, 2023.
Article in English | MEDLINE | ID: mdl-36891256

ABSTRACT

Background: Greater mindfulness, the practice of awareness and living in the moment without judgement, has been linked to positive caregiving outcomes in dementia caregivers and its impact attributed to greater decentering and emotion regulation abilities. Whether the impact of these mindfulness-based processes varies across caregiver subgroups is unclear. Objective: Analyze cross-sectional associations between mindfulness and caregiver psychosocial outcomes, considering different caregiver and patient characteristics. Methods: A total of 128 family caregivers of persons living with Alzheimer's disease and related disorders were assessed on several mindfulness measures (i.e., global; decentering, positive emotion regulation, negative emotion regulation) and provided self-reported appraisals of caregiving experience; care preparedness; confidence, burden, and depression/anxiety. Bivariate relationships between mindfulness and caregiver outcomes were assessed with Pearson's correlations and stratified by caregiver (women versus men; spouse versus adult child) and patient (mild cognitive impairment (MCI) versus Dementia; AD versus dementia with Lewy bodies; low versus high symptom severity) characteristics. Results: Greater mindfulness was associated with positive outcomes and inversely associated with negative outcomes. Stratification identified specific patterns of associations across caregiver groups. Significant correlations were found between all mindfulness measures and caregiving outcomes in male and MCI caregivers while the individual mindfulness component of positive emotion regulation was significantly correlated to outcomes in most caregiver groups. Conclusion: Our findings support a link between caregiver mindfulness and improved caregiving outcomes and suggest directions of inquiry into whether the effectiveness of dementia caregiver-support interventions may be improved by targeting specific mindfulness processes or offering a more inclusive all-scope approach depending on individual caregiver or patient characteristics.

7.
J Alzheimers Dis ; 84(4): 1729-1746, 2021.
Article in English | MEDLINE | ID: mdl-34744081

ABSTRACT

BACKGROUND: There is increasing interest in lifestyle modification and integrative medicine approaches to treat and/or prevent mild cognitive impairment (MCI) and Alzheimer's disease and related dementias (ADRD). OBJECTIVE: To address the need for a quantifiable measure of brain health, we created the Resilience Index (RI). METHODS: This cross-sectional study analyzed 241 participants undergoing a comprehensive evaluation including the Clinical Dementia Rating and neuropsychological testing. Six lifestyle factors including physical activity, cognitive activity, social engagements, dietary patterns, mindfulness, and cognitive reserve were combined to derive the RI (possible range of scores: 1-378). Psychometric properties were determined. RESULTS: The participants (39 controls, 75 MCI, 127 ADRD) had a mean age of 74.6±9.5 years and a mean education of 15.8±2.6 years. The mean RI score was 138.2±35.6. The RI provided estimates of resilience across participant characteristics, cognitive staging, and ADRD etiologies. The RI showed moderate-to-strong correlations with clinical and cognitive measures and very good discrimination (AUC: 0.836; 95% CI: 0.774-0.897) between individuals with and without cognitive impairment (diagnostic odds ratio = 8.9). Individuals with high RI scores (> 143) had better cognitive, functional, and behavioral ratings than individuals with low RI scores. Within group analyses supported that controls, MCI, and mild ADRD cases with high RI had better cognitive, functional, and global outcomes than those with low RI. CONCLUSION: The RI is a brief, easy to administer, score and interpret assessment of brain health that incorporates six modifiable protective factors. Results from the RI could provide clinicians and researchers with a guide to develop personalized prevention plans to support brain health.


Subject(s)
Brain/physiology , Cognitive Dysfunction/diagnosis , Dementia/diagnosis , Health Status , Neuropsychological Tests/statistics & numerical data , Aged , Aged, 80 and over , Cognitive Reserve , Cross-Sectional Studies , Exercise , Female , Humans , Male , Mental Status and Dementia Tests , Social Interaction
8.
J Alzheimers Dis ; 82(4): 1755-1768, 2021.
Article in English | MEDLINE | ID: mdl-34219721

ABSTRACT

BACKGROUND: Although an efficacious dementia-risk score system, Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) was derived using midlife risk factors in a population with low educational attainment that does not reflect today's US population, and requires laboratory biomarkers, which are not always available. OBJECTIVE: Develop and validate a modified CAIDE (mCAIDE) system and test its ability to predict presence, severity, and etiology of cognitive impairment in older adults. METHODS: Population consisted of 449 participants in dementia research (N = 230; community sample; 67.9±10.0 years old, 29.6%male, 13.7±4.1 years education) or receiving dementia clinical services (N = 219; clinical sample; 74.3±9.8 years old, 50.2%male, 15.5±2.6 years education). The mCAIDE, which includes self-reported and performance-based rather than blood-derived measures, was developed in the community sample and tested in the independent clinical sample. Validity against Framingham, Hachinski, and CAIDE risk scores was assessed. RESULTS: Higher mCAIDE quartiles were associated with lower performance on global and domain-specific cognitive tests. Each one-point increase in mCAIDE increased the odds of mild cognitive impairment (MCI) by up to 65%, those of AD by 69%, and those for non-AD dementia by > 85%, with highest scores in cases with vascular etiologies. Being in the highest mCAIDE risk group improved ability to discriminate dementia from MCI and controls and MCI from controls, with a cut-off of ≥7 points offering the highest sensitivity, specificity, and positive and negative predictive values. CONCLUSION: mCAIDE is a robust indicator of cognitive impairment in community-dwelling seniors, which can discriminate well between dementia severity including MCI versus controls. The mCAIDE may be a valuable tool for case ascertainment in research studies, helping flag primary care patients for cognitive testing, and identify those in need of lifestyle interventions for symptomatic control.


Subject(s)
Cognitive Dysfunction/diagnosis , Mass Screening , Neuropsychological Tests/statistics & numerical data , Aged , Aging/physiology , Female , Humans , Male , Risk Factors , United States
9.
Alzheimers Dement (N Y) ; 7(1): e12134, 2021.
Article in English | MEDLINE | ID: mdl-33816759

ABSTRACT

INTRODUCTION: Potentially modifiable dementia risk factors include diet and physical and cognitive activity. However, there is a paucity of scales to quantify cognitive activities. To address this, we developed the Cognitive & Leisure Activity Scale (CLAS). METHODS: The CLAS was validated in 318 consecutive individuals with and without cognitive impairment. Psychometric properties were compared with sample characteristics, disease stage, and etiology. RESULTS: The CLAS has very good data quality (Cronbach alpha: 0.731; 95% confidence interval: 0.67-0.78). CLAS scores correlated with gold standard measures of cognition, function, physical functionality, behavior, and caregiver burden. CLAS scores were positively correlated with other resilience factors (eg, diet, physical activity) and negatively correlated with vulnerability factors (eg, older age, frailty). DISCUSSION: The CLAS is a brief inventory to estimate dosage of participation in cognitive activities. The CLAS could be used in clinical care to enhance cognitive activity or in research to estimate dosage of activities prior to an intervention.

10.
Alzheimers Dement ; 17(10): 1675-1686, 2021 10.
Article in English | MEDLINE | ID: mdl-33793069

ABSTRACT

INTRODUCTION: The National Institute on Aging Alzheimer's Disease Research Center program added the Lewy body dementia module (LBD-MOD) to the Uniform Data Set to facilitate LBD characterization and distinguish dementia with Lewy bodies (DLB) from Alzheimer's disease (AD). We tested the performance of the LBD-MOD. METHODS: The LBD-MOD was completed in a single-site study in 342 participants: 53 controls, 78 AD, and 110 DLB; 79 mild cognitive impairment due to AD (MCI-AD); and 22 MCI-DLB. RESULTS: DLB differed from AD in extrapyramidal symptoms, hallucinations, apathy, autonomic features, REM sleep behaviors, daytime sleepiness, cognitive fluctuations, timed attention tasks, and visual perception. MCI-DLB differed from MCI-AD in extrapyramidal features, mood, autonomic features, fluctuations, timed attention tasks, and visual perception. Descriptive data on LBD-MOD measures are provided for reference. DISCUSSION: The LBD-MOD provided excellent characterization of core and supportive features to differentiate DLB from AD and healthy controls while also characterizing features of MCI-DLB.


Subject(s)
Cognitive Dysfunction/diagnosis , Diagnosis, Differential , Lewy Body Disease/diagnosis , Aged , Alzheimer Disease/diagnosis , Cross-Sectional Studies , Female , Humans , Male , Neuropsychological Tests , Parkinsonian Disorders/etiology , REM Sleep Behavior Disorder/etiology
11.
J Alzheimers Dis ; 79(3): 1345-1367, 2021.
Article in English | MEDLINE | ID: mdl-33427746

ABSTRACT

BACKGROUND: Mindfulness is the practice of awareness and living in the present moment without judgment. Mindfulness-based interventions may improve dementia-related outcomes. Before initiating interventions, it would be beneficial to measure baseline mindfulness to understand targets for therapy and its influence on dementia outcomes. OBJECTIVE: This cross-sectional study examined patient and caregiver mindfulness with patient and caregiver rating scales and patient cognitive performance and determined whether dyadic pairing of mindfulness influences patient outcomes. METHODS: Individuals (N = 291) underwent comprehensive evaluations, with baseline mindfulness assessed using the 15-item Applied Mindfulness Process Scale (AMPS). Correlation, regression, and mediation models tested relationships between patient and caregiver mindfulness and outcomes. RESULTS: Patients had a mean AMPS score of 38.0±11.9 and caregivers had a mean AMPS score of 38.9±11.5. Patient mindfulness correlated with activities of daily living, behavior and mood, health-related quality of life, subjective cognitive complaints, and performance on episodic memory and attention tasks. Caregiver mindfulness correlated with preparedness, care confidence, depression, and better patient cognitive performance. Patients in dyads with higher mindfulness had better cognitive performance, less subjective complaints, and higher health-related quality of life (all p-values<0.001). Mindfulness effects on cognition were mediated by physical activity, social engagement, frailty, and vascular risk factors. CONCLUSION: Higher baseline mindfulness was associated with better patient and caregiver outcomes, particularly when both patients and caregivers had high baseline mindfulness. Understanding the baseline influence of mindfulness on the completion of rating scales and neuropsychological test performance can help develop targeted interventions to improve well-being in patients and their caregivers.


Subject(s)
Caregivers/psychology , Dementia/therapy , Mindfulness , Adult , Aged , Aged, 80 and over , Caregivers/statistics & numerical data , Cross-Sectional Studies , Dementia/psychology , Female , Humans , Male , Mental Status and Dementia Tests , Middle Aged , Mindfulness/methods , Mindfulness/statistics & numerical data , Resilience, Psychological , Retrospective Studies , Risk Factors , Surveys and Questionnaires , Treatment Outcome , Young Adult
12.
Article in English | MEDLINE | ID: mdl-33123214

ABSTRACT

OBJECTIVE: Early detection of mild cognitive impairment (MCI) and Alzheimer's disease (AD) can increase access to treatment and assist in advance care planning. However, the development of a diagnostic system that d7oes not heavily depend on cognitive testing is a major challenge. We describe a diagnostic algorithm based solely on gait and machine learning to detect MCI and AD from healthy. METHODS: We collected "single-tasking" gait (walking) and "dual-tasking" gait (walking with cognitive tasks) from 32 healthy, 26 MCI, and 20 AD participants using a computerized walkway. Each participant was assessed with the Montreal Cognitive Assessment (MoCA). A set of gait features (e.g., mean, variance and asymmetry) were extracted. Significant features for three classifications of MCI/healthy, AD/healthy, and AD/MCI were identified. A support vector machine model in a one-vs.-one manner was trained for each classification, and the majority vote of the three models was assigned as healthy, MCI, or AD. RESULTS: The average classification accuracy of 5-fold cross-validation using only the gait features was 78% (77% F1-score), which was plausible when compared with the MoCA score with 83% accuracy (84% F1-score). The performance of healthy vs. MCI or AD was 86% (88% F1-score), which was comparable to 88% accuracy (90% F1-score) with MoCA. CONCLUSION: Our results indicate the potential of machine learning and gait assessments as objective cognitive screening and diagnostic tools. SIGNIFICANCE: Gait-based cognitive screening can be easily adapted into clinical settings and may lead to early identification of cognitive impairment, so that early intervention strategies can be initiated.

13.
Clin Interv Aging ; 15: 2249-2263, 2020.
Article in English | MEDLINE | ID: mdl-33293802

ABSTRACT

PURPOSE: To assess age, sex, race and ethnicity disparities in cognitive function in community-dwelling older adults and identify factors that contribute to these disparities. PATIENTS AND METHODS: Cognitive performance (global and domain-specific) and self-reported cognitive function were compared among Black (N=57), Hispanic (N=139), and White (N=108) older adults. The impact of socioeconomic status (SES), physical functionality, and mood indicators was assessed with a combination of hierarchical general linear models and mediation analysis. RESULTS: Poorer cognitive performance and higher levels of impairment were found in older adults from racial and ethnic backgrounds. The contribution of lower SES to the observed racial and ethnic disparities in objective cognitive performance was 33% in Hispanics and about 20% in Blacks, while poorer physical functionality explained over half of the differences between Black and White participants. Higher self-reported cognitive impairment in minorities was explained by lower SES and higher depressive symptoms in Hispanics but not in Blacks. CONCLUSION: Performance on objective memory testing and self-reported cognition are greatly influenced by relevant biological, sociodemographic and medical variables. Dementia screening programs should be tailored to individual sociodemographic groups based on contributors that are specific to each group.


Subject(s)
Affect , Black People/statistics & numerical data , Dementia/ethnology , Hispanic or Latino/statistics & numerical data , Mass Screening/statistics & numerical data , White People/statistics & numerical data , Aged , Cognitive Dysfunction/ethnology , Cohort Studies , Female , Health Status Disparities , Humans , Male , Social Class , United States
14.
Alzheimers Dement (N Y) ; 6(1): e12104, 2020.
Article in English | MEDLINE | ID: mdl-33283038

ABSTRACT

INTRODUCTION: Dementia caregiving is often examined as a monolithic experience describing the challenges caregivers face, exploring one construct at a time, with little research on the positive experiences of caregiving. To address this, we developed the Positive and Negative Appraisals of Caregiving (PANAC) scale. METHODS: PANAC was validated in 253 patient-caregiver dyads. Factor analyses revealed a two-factor solution: Positive Appraisals (PAs) and Negative Appraisals (NAs). Psychometric properties were compared with patient and caregiver characteristics and outcomes, disease stage, and etiology. RESULTS: Internal consistency was good with Cronbach's alpha: 0.82 NA and 0.80 PA (P  < 0.001). NA correlated with patient and caregiver characteristics, whereas PA correlated only with caregiver characteristics. The PA/NA ratio could be used to capture change due to an intervention. DISCUSSION: The PANAC scale is a useful measure of the overall caregiver experience accounting for negative and positive experiences and may be used to tailor support to individual caregivers.

15.
PLoS One ; 15(11): e0242233, 2020.
Article in English | MEDLINE | ID: mdl-33253192

ABSTRACT

INTRODUCTION: Alzheimer's disease and related dementias (ADRD) affect over 5.7 million Americans and over 35 million people worldwide. Detection of mild cognitive impairment (MCI) and early ADRD is a challenge to clinicians and researchers. Brief assessment tools frequently emphasize memory impairment, however executive dysfunction may be one of the earliest signs of impairment. To address the need for a brief, easy-to-score, open-access test of executive function for use in clinical practice and research, we created the Number Symbol Coding Task (NSCT). METHODS: This study analyzed 320 consecutive patient-caregiver dyads who underwent a comprehensive evaluation including the Clinical Dementia Rating (CDR), patient and caregiver versions of the Quick Dementia Rating System (QDRS), caregiver ratings of behavior and function, and neuropsychological testing, with a subset undergoing volumetric magnetic resonance imaging (MRI). Estimates of cognitive reserve were calculated using education, combined indices of education and occupation, and verbal IQ. Psychometric properties of the NSCT including data quality, data distribution, floor and ceiling effects, construct and known-groups validity, discriminability, and clinical profiles were determined. RESULTS: The patients had a mean age of 75.3±9.2 years (range 38-98y) with a mean education of 15.7±2.8 years (range 6-26y) of education. The patients had a mean CDR-SB of 4.8±4.7 (range 0-18) and a mean MoCA score of 18.6±7.1 (range 1-30). The mean NSCT score was 30.1±13.8 and followed a normal distribution. All healthy controls and MCI cases were able to complete the NSCT. The NSCT showed moderate-to-strong correlations with clinical and neuropsychological measures with the strongest association (all p's < .001) for measures with executive components (e.g., Judgement and Problem Solving box of the CDR, Decision Making and Problem Solving domain of the QDRS, Trailmaking B, and Cognigram Attention and Executive Composite Scores). Women slightly outperformed men, and individuals with lower educational attainment and lower education-occupation indices had lower NSCT scores. Decreasing NSCT scores corresponded to older age, worse cognitive scores, higher CDR sum of boxes scores, worse caregiver ratings of function and behavior, worse patient and informant QDRS ratings, and smaller hippocampal volumes and hippocampal occupancy scores. The NSCT provided excellent discrimination (AUC: .866; 95% CI: .82-.91) with a cut-off score of 36 providing the best combination of sensitivity (0.880) and specificity (0.759). Combining the NSCT with patient QDRS and caregiver QDRS ratings improved discrimination (AUC: .908; 95% CI: .87-.94). DISCUSSION: The NSCT is a brief, 90-second executive task that incorporates attention, planning and set-switching that can be completed by individuals into the moderate-to-severe stages of dementia. The NSCT may be a useful tool for dementia screening, case-ascertainment in epidemiological or community-based ADRD studies, and in busy primary care settings where time is limited. Combining the NSCT with a brief structured interview tool such as the QDRS may provide excellent power to detect cognitive impairment. The NSCT performed well in comparison to standardized scales of a comprehensive cognitive neurology evaluation across a wide array of sociodemographic variables in a brief fashion that could facilitate its use in clinical care and research.


Subject(s)
Cognitive Dysfunction/diagnosis , Dementia/diagnosis , Executive Function/physiology , Psychometrics/methods , Adult , Aged , Aged, 80 and over , Area Under Curve , Caregivers/psychology , Cognitive Dysfunction/pathology , Dementia/pathology , Female , Hippocampus/diagnostic imaging , Hippocampus/physiology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , ROC Curve , Severity of Illness Index
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3204-3207, 2020 07.
Article in English | MEDLINE | ID: mdl-33018686

ABSTRACT

Alzheimer's disease (AD) affects approximately 30 million people worldwide, and this number is predicted to triple by 2050 unless further discoveries facilitate the early detection and prevention of the disease. Computerized walkways for simultaneous assessment of motor-cognitive performance, known as a dual-task assessment, has been used to associate changes in gait characteristics to mild cognitive impairment (MCI) with early-stage disease. However, to our best knowledge, there is no validated method to detect MCI using the collective analysis of these gait characteristics. In this paper, we develop a machine learning approach to analyze the gait data from the dual-task assessment in order to detect subjects with cognitive impairment from healthy individuals. We collected dual-task gait data from a computerized walkway of a total of 92 subjects with 31 healthy control (HC) and 61 MCI. Using support vector machine (SVM) and gradient tree boosting, we developed a classifier to differentiate MCI from HC subjects and compared the results with a paper-based questionnaire assessment that has been commonly used in clinical practice. SVM provided the highest accuracy of 77.17% with 81.97% sensitivity and 67.74% specificity. Our results indicate the potential of machine learning + dual-task assessment to enable early diagnosis of cognitive decline before it advances to dementia and AD, so that early intervention or prevention strategies can be initiated.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Alzheimer Disease/diagnosis , Cognitive Dysfunction/diagnosis , Early Diagnosis , Gait , Humans , Machine Learning
17.
PLoS One ; 15(10): e0241641, 2020.
Article in English | MEDLINE | ID: mdl-33125429

ABSTRACT

INTRODUCTION: Alzheimer's disease and related dementias (ADRD) currently affect over 5.7 million Americans and over 35 million people worldwide. At the same time, over 31 million older adults are physically inactive with impaired physical performance interfering with activities of daily living. Low physical activity is a risk factor for ADRD. We examined the utility of a new measure, the Quick Physical Activities Rating (QPAR) as an informant-rated instrument to quantify the dosage of physical activities in healthy controls, MCI and ADRD compared with Gold Standard assessments of objective measures of physical performance, fitness, and functionality. METHODS: This study analyzed 390 consecutive patient-caregiver dyads who underwent a comprehensive evaluation including the Clinical Dementia Rating (CDR), mood, neuropsychological testing, caregiver ratings of patient behavior and function, and a comprehensive physical performance and gait assessment. The QPAR was completed prior to the office visit and was not considered in the clinical evaluation, physical performance assessment, staging or diagnosis of the patient. Psychometric properties including item variability and distribution, floor and ceiling effects, strength of association, known-groups performance, and internal consistency were determined. RESULTS: The patients had a mean age of 75.3±9.2 years, 15.7±2.8 years of education and were 46.9% female. The patients had a mean CDR-SB of 4.8±4.7 and a mean MoCA score of 18.6±7.1 and covered a range of healthy controls (CDR 0 = 54), MCI or very mild dementia (CDR 0.5 = 161), mild dementia (CDR 1 = 92), moderate dementia (CDR 2 = 64), and severe dementia (CDR 3 = 29). The mean QPAR score was 20.2±18.9 (range 0-132) covering a wide range of physical activity. The QPAR internal consistency (Cronbach alpha) was very good at 0.747. The QPAR was correlated with measures of physical performance (dexterity, grip strength, gait, mobility), physical functionality rating scales, measures of activities of daily living and comorbidities, the UPDRS, and frailty ratings (all p < .001). The QPAR report of physical activities was able to discriminate between individuals with impaired physical functionality (32.2±23.9 vs 15.2±13.8, p < .001), falls risk (28.4±21.6 vs. 14.5±13.2, p < .001), and the presence of frailty (28.1±22.7 vs. 11.8±9.4, p < .001). The QPAR showed strong psychometric properties and excellent data quality, and worked equally well across different patient ages, sexes, informant relationships, and in individuals with and without cognitive impairment. DISCUSSION: The QPAR is a brief detection tool that captures informant reports of physical activities and differentiates individuals with normal physical functionality from those individuals with impaired physical functionality. The QPAR correlated with Gold Standard assessments of strength and sarcopenia, activities of daily living, gait and mobility, fitness, health related quality of life, frailty, global physical performance, and provided good discrimination between states of physical functionality, falls risk, and frailty. The QPAR performed well in comparison to standardized scales of objective physical performance, but in a brief fashion that could facilitate its use in clinical care and research.


Subject(s)
Cognitive Dysfunction/diagnosis , Exercise , Physical Functional Performance , Activities of Daily Living , Aged , Aged, 80 and over , Female , Humans , Male , Quality of Life
18.
PLoS One ; 15(10): e0240422, 2020.
Article in English | MEDLINE | ID: mdl-33057404

ABSTRACT

INTRODUCTION: Community detection of mild cognitive impairment (MCI) and Alzheimer's disease and related disorders (ADRD) is a challenge. While Gold Standard assessments are commonly used in research centers, these methods are time consuming, require extensive training, and are not practical in most clinical settings or in community-based research projects. Many of these methods require an informant (e.g., spouse, adult child) to provide ratings of the patients' cognitive and functional abilities. A patient-reported outcome that captures the presence of cognitive impairment and corresponds to Gold Standard assessments could improve case ascertainment, clinical care, and recruitment into clinical research. We tested the patient version of the Quick Dementia Rating System (QDRS) as a patient-reported outcome to detect MCI and ADRD. METHODS: The patient QDRS was validated in a sample of 261 consecutive patient-caregiver dyads compared with the informant version of the QDRS, the Clinical Dementia Rating (CDR), neuropsychological tests, and Gold Standard measures of function, behavior, and mood. Psychometric properties including item variability, floor and ceiling effects, construct, concurrent, and known-groups validity, and internal consistency were determined. RESULTS: The patient QDRS strongly correlated with Gold Standard measures of cognition, function, mood, behavior, and global staging methods (p-values < .001) and had strong psychometric properties with excellent data quality and internal consistency (Cronbach alpha = 0.923, 95%CI:0.91-0.94). The patient QDRS had excellent agreement with the informant QDRS, the CDR and its sum of boxes (Intraclass Correlation Coefficients: 9.781-0.876). Receiver operator characteristic curves showed excellent discrimination between normal controls from CDR 0.5 (AUC:0.820;95% CI: 0.74-0.90) and for normal controls from any cognitive impairment (AUC:0.885;95% CI: 0.83-0.94). DISCUSSION: The patient QDRS validly and reliably differentiates individuals with and without cognitive impairment and can be completed by patients through all stages of dementia. The patient QDRS is highly correlated with Gold Standard measures of cognitive, function, behavior, and global staging. The patient QDRS provides a rapid method to screen patients for MCI and ADRD in clinical practice, determine study eligibility, improve case ascertainment in community studies.


Subject(s)
Cognitive Dysfunction/pathology , Dementia/pathology , Patient Reported Outcome Measures , Aged , Aged, 80 and over , Area Under Curve , Case-Control Studies , Cognitive Dysfunction/diagnosis , Dementia/diagnosis , Female , Humans , Male , Mental Status and Dementia Tests/standards , Psychiatric Status Rating Scales/standards , ROC Curve
19.
PLoS One ; 15(7): e0235534, 2020.
Article in English | MEDLINE | ID: mdl-32609745

ABSTRACT

INTRODUCTION: Alzheimer's disease and related dementias (ADRD) and mild cognitive impairment (MCI) are often under-recognized in the community. MCI/ADRD screening could offer benefits such as early treatment, research participation, lifestyle modification, and advanced care planning. To date, there are no clear guidelines regarding the benefits vs. harms of dementia screening or whether a dementia screening program could be successful. METHODS: A community-based study was conducted to evaluate an MCI/ADRD screening program and determine what older adults would do with the information. Measures of cognition, physical health, functionality, and mood were collected. Participants met with a health professional, were given screening results with recommendations, and then contacted 60 days later to determine what was done with the results. Logistic regression models were used to build predictive models. RESULTS: Participants (n = 288) had a mean age of 71.5±8.3y, mean education of 13.3±4.8y, and were 70% female, 67% White, 26% African American, and 48% Hispanic. After 60 days, 75% of participants were re-contacted; 54% shared results with family, 33% shared results with health care providers (HCPs), and 52% initiated behavioral change. Among participants sharing results with HCPs, 51% reported HCPs did not follow-up on the results, and 18% that HCPs did not show any interest in the screening visit or its results. Predictors of sharing results with HCPs were elevated hemoglobin A1C (OR = 1.85;95%CI:1.19-2.88), uncontrolled hypertension (OR = 2.73;95%CI:1.09-6.83), and mobility issues (OR = 2.43;95%CI: 1.93-5.54). Participant behavioral changes included lifestyle modification (58%), social engagement (10%), cognitive stimulation (5%), and advanced care planning (4%). The most significant predictors of sharing with family were better overall mental health (OR = 0.19; 95%CI: 0.06-0.59) and better physical function (OR = 0.38; 95%CI: 0.17-0.81). DISCUSSION: MCI/ADRD screening was well-received by a diverse community sample. Participants showed interest in sharing the results with their family and HCPs and many attempted behavioral change. While HCPs did not always act on screening results, 25% ordered further testing and evaluation. Efforts need to be directed toward (1) increasing self-efficacy of older adults to discuss screening results with their HCPs, and (2) educating HCPs on the value of early detection of MCI/ADRD. Community dementia screening programs can increase MCI/ADRD detection and improve patient-centered outcomes and medical decision-making.


Subject(s)
Dementia/diagnosis , Mass Screening/psychology , Affect , Aged , Aged, 80 and over , Cognition , Cross-Sectional Studies , Dementia/physiopathology , Dementia/psychology , Demography , Female , Humans , Male , Mass Screening/statistics & numerical data , Middle Aged , Patient Compliance/statistics & numerical data , Residence Characteristics/statistics & numerical data
20.
Article in English | MEDLINE | ID: mdl-32230914

ABSTRACT

A random digit dialing sample from Missouri (USA) was used to compare associations between psychosocial factors and Alzheimer's disease (AD) screening intention based on residential locale. Linear regression associations between demographics and five psychosocial constructs (dementia knowledge, perceived screening benefits, preventive health behaviors, perceived susceptibility, and self-efficacy) and screening intention were compared by residential locale. Participants (n = 932) had a mean age of 62 years (urban: n = 375; suburban: n = 319, rural: n = 238). African Americans more often lived in urban than suburban/rural neighborhoods, and more urban than suburban/rural residents reported insufficient income. Preventative health behaviors (e.g., dentist visits) were higher in urban and suburban versus rural participants. AD screening intention did not differ by residential locale. Among urban participants, self-efficacy to get screened was associated with screening intention. Among rural participants, dementia knowledge was associated with screening intention. Perceived screening benefits and perceived susceptibility to AD were associated with screening intention regardless of locale. Unlike urban participants, rural participants demonstrated greater screening intention with greater dementia knowledge. Our findings suggest that psychosocial factors associated with AD screening intention differ depending on residential locale. Strategies to increase dementia screening may need to account for regional variations to be maximally effective.


Subject(s)
Alzheimer Disease , Health Behavior , Intention , Black or African American , Alzheimer Disease/diagnosis , Alzheimer Disease/ethnology , Female , Humans , Mass Screening , Middle Aged , Missouri , Residence Characteristics , Rural Population
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