Detection of Mild Cognitive Impairment Among Community-Dwelling African Americans Using the Montreal Cognitive Assessment

Meta-analysis of Montreal cognitive assessment diagnostic accuracy in amnestic mild cognitive impairment

Background

The Montreal Cognitive Assessment (MoCA) is one of the most widely-used cognitive screening instruments and has been translated into several different languages and dialects. Although the original validation study suggested to use a cutoff of ≤26, subsequent studies have shown that lower cutoff values may yield fewer false-positive indications of cognitive impairment. The aim of this study was to summarize the diagnostic accuracy and mean difference of the MoCA when comparing cognitively unimpaired (CU) older adults to those with amnestic mild cognitive impairment (aMCI).

Methods

PubMed and EMBASE databases were searched from inception to 22 February 2022. Meta-analyses for area under the curve (AUC) and standardized mean difference (SMD) values were performed.

Results

Fifty-five observational studies that included 17,343 CU and 8,413 aMCI subjects were selected for inclusion. Thirty-nine studies were used in the AUC analysis while 44 were used in the SMD analysis. The overall AUC value was 0.84 (95% CI: 0.81, 0.87) indicating good diagnostic accuracy and a large effect size was noted for the SMD analysis (Hedge's g = 1.49, 95% CI: 1.33, 1.64). Both analyses had high levels of between-study heterogeneity. The median cutoff score for identifying aMCI was <24.

Discussion and conclusion

The MoCA has good diagnostic accuracy for detecting aMCI across several different languages. The findings of this meta-analysis also support the use of 24 as the optimal cutoff when the MoCA is used to screen for suspected cognitive impairment.

Frequency and correlates of subjective cognitive complaints and objective cognitive screening results in African American adults following COVID-19 infection

Background

Subjective cognitive complaints are frequent following COVID-19 infection, but assessment of whether these complaints map onto objective cognitive findings may not be routine in busy clinical settings. Consequently, opportunities to confirm these complaints and to provide follow-up referrals and appropriate care may be missed, thereby impacting patients' functional independence and quality of life. African Americans are vulnerable to poor outcomes from COVID-19, and thus represent a minority group in whom subjective concerns are especially important to investigate. Towards this end, we examined the frequency and correlates of subjective complaints and objective screening results of African American patients referred to the Post-Acute Sequelae of SARS-CoV-2 (PASC) Clinic at Grady Memorial Hospital, a large county teaching hospital in Atlanta, Georgia.

Methods

Eighty seven African American patients (mean age = 52.5, SD = 10.5, range = 30-73) were evaluated between January 28, 2021-October 14, 2021 in the Grady PASC clinic. They ranged from 1 to 17 months post positive SARS-COV-2 antigen testing. Patients were administered a subjective cognitive complaint questionnaire (PROMIS Cognitive Function Scale Short Form 8a) as well as cognitive screening measures including the Mini-Cog (3 item recall, clock) and the Digit Symbol Substitution Test (timed visuomotor sequencing). Mood was assessed via the Patient Health Questionnaire-9, and anxiety via the Generalized Anxiety Disorders Scale. Published norms were used to identify clinically elevated scores.

Results

Sixty six (76%) patients denied experiencing meaningful cognitive concerns, and of these, 25 (38%) had positive cognitive screens indicating impaired performance on objective testing. Of 21 patients with subjectively elevated cognitive concerns, 17 (81%) also had positive cognitive screens. There were no significant differences in sociodemographic factors (p values = .07-.71), days post-acute positive SARS-COV-2 Antigen Test (p = .99), disease severity (p values = .67-.75), or COVID-19 comorbidity indices (medical conditions (p values = .20-.77), substance abuse (p = .79), psychiatric history (p values = .11-.99) in those with or without subjective complaints and objective cognitive findings. However, patients with subjective complaints and objective cognitive findings reported more post-COVID-19 anxiety (p = .02) and depression (p = .001).

Conclusions

Findings indicate a high concordance between subjective complaints on the PROMIS Cognitive Scale and objectively confirmed cognitive impairments in African Americans. Further, almost 40% who reported no cognitive complaints screened positive for cognitive impairment. Although depression and anxiety are associated with subjective complaints, they do not account for positive cognitive screening results, as those patients without depressive complaints also had similar rates of positive objective screens. The findings suggest that cognitive screening using assessment tools should be routinely performed in African Americans, especially those reporting cognitive symptoms on outcome scales. While future studies are needed to assess long-term outcomes, we highly recommend follow-ups in those with positive screens to characterize the specific domains that are impacted and that could affect activities of daily living and quality of life.

Subjective cognitive complaints in White and African American older adults: associations with demographic, mood, cognitive, and neuroimaging features

Subjective cognitive complaints (SCC) in cognitively intact older adults have been investigated as a clinically important symptom that may portend the onset of a neurodegenerative disorder such as Alzheimer's disease. Few studies have concurrently incorporated demographic features, depressive symptoms, neuropsychological status, and neuroimaging correlates of SCC and evaluated whether these differ in White and African American older adults. In the current study, 131 (77 White, 54 African American) healthy participants ≥50 years old completed the Cognitive Function Instrument (CFI) to assess SCC, and they underwent objective cognitive testing, assessment of mood, and brain magnetic resonance imaging. Pearson Product Moment correlations were performed to evaluate associations of the CFI self-ratings with the above measures for the combined group and separately for White and African American participants. SCC were associated with greater depressive symptoms in both White and African American participants in adjusted models controlling for overall cognitive status, education, and hypertension. Greater white matter hyperintensities, lower cortical thickness, older age, and slower set shifting speed were associated with increased SCC in White participants. Although the correlations were not significant for African Americans, the strength of the associations were comparable to White participants. Hippocampal volume was not associated with either total SCC or items specific to memory functioning in the entire group. Longitudinal studies are needed to further evaluate the clinical significance of these associations with risk of conversion to mild cognitive impairment and dementia.

Conventional clock drawing tests have low to moderate reliability and validity for detecting subtle cognitive impairments in community-dwelling older adults

Background

Early identification of subtle cognitive decline in community-dwelling older adults is critical, as mild cognitive impairment contributes to disability and can be a precursor to dementia. The clock drawing test (CDT) is a widely adopted cognitive screening measure for dementia, however, the reliability and validity of paper-and-pencil CDT scoring scales for mild cognitive impairment in community samples of older adults is less well established. We examined the reliability, sensitivity and specificity, and construct validity of two free-drawn clock drawing test scales-the Rouleau System and the Clock Drawing Interpretation Scale (CDIS)-for subtle cognitive decline in community-dwelling older adults.

Methods

We analyzed Rouleau and CDIS scores of 310 community-dwelling older adults who had MoCA scores of 20 or above. For each scale we computed Cronbach's alpha, receiver operating characteristic curves (ROC) for sensitivity and specificity using the MoCA as the index measure, and item response theory models for difficulty level.

Results

Our sample was 75% female and 85% Caucasian with a mean education of 16 years. The Rouleau scale had excellent interrater reliability (94%), poor internal consistency [0.37 (0.48)], low sensitivity (0.59) and moderate specificity (0.71) at a score of 9. The CDIS scale had good interrater reliability (88%), moderate internal consistency [0.66 (0.09)], moderate sensitivity (0.78) and low specificity (0.45) at a score of 19. In the item response models, both scales' total scores gave the most information at lower cognitive levels.

Conclusion

In our community-dwelling sample, the CDIS's psychometric properties were better in most respects than the Rouleau for use as a screening instrument. Both scales provide valuable information to clinicians screening older adults for cognitive change, but should be interpreted in the setting of a global cognitive battery and not as stand-alone instruments.

Classification statistics of the Montreal Cognitive Assessment (MoCA): Are we interpreting the MoCA correctly?

OBJECTIVE

The Montreal Cognitive Assessment (MoCA) is a common cognitive screener for detecting mild cognitive impairment (MCI). However, previously suggested cutoff scores of 26/30 and above is often criticized and lacks racial diversity. The purpose of this study is to investigate the potential influence of race on MoCA classification cutoff score accuracy.

METHOD

Data were obtained from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set and yielded 4,758 total participants. Participants were predominately White (82.8%) and female (61.7%) with a mean age of 69.3 years (SD = 10.3) and education level of 16.3 years (SD = 2.6). Based on NACC's classification, participants were either cognitively normal (n = 3,650) or MCI (n = 1,108).

RESULTS

Sensitivity and specificity analyses revealed that when using the cutoff score of ≤26/30, the MoCA correctly classified 73.2% of White cognitively normal participants and 83.1% of White MCI participants. In contrast, this criterion correctly classified 40.5% of Black cognitively normal participants and 90.8% of Black MCI participants. Our sample was highly educated; therefore, we did not observe significant differences in scores when accounting for education across race. Classification statistics are presented.

CONCLUSIONS

Black participants were misclassified at a higher rate than White participants when applying the ≤26/30 cutoff score. We suggest cutoff scores of ≤25/30 be applied to White persons and ≤22/30 for Black persons. These findings highlight the need for racially stratified population-based norms given the high misclassification of Black participants without such adjustment.

Comparing the gut microbiome of obese, African American, older adults with and without mild cognitive impairment

Those with mild cognitive impairment (MCI), a precursor to dementia, have a gut microbiome distinct from healthy individuals, but this has only been shown in healthy individuals, not in those exhibiting several risk factors for dementia. Using amplicon 16S rRNA gene sequencing in a case-control study of 60 older (ages 55-76), obese, predominately female, African American adults, those with MCI (cases) had different gut microbiota profiles than controls. While microbial community diversity was similar between cases and controls, the abundances of specific microbial taxa weren't, such as Parabacteroides distasonis (lower in cases) and Dialister invisus (higher in cases). These differences disappeared after adjusting for markers of oxidative stress and systemic inflammation. Cognitive scores were positively correlated with levels of Akkermansia muciniphila, a bacterium associated with reduced inflammation. Our study shows that gut microbial composition may be associated with inflammation, oxidative stress, and MCI in those at high risk for dementia.

Patterns of structure-function association in normal aging and in Alzheimer's disease: Screening for mild cognitive impairment and dementia with ML regression and classification models

Background

The combined analysis of imaging and functional modalities is supposed to improve diagnostics of neurodegenerative diseases with advanced data science techniques.

Objective

To get an insight into normal and accelerated brain aging by developing the machine learning models that predict individual performance in neuropsychological and cognitive tests from brain MRI. With these models we endeavor to look for patterns of brain structure-function association (SFA) indicative of mild cognitive impairment (MCI) and Alzheimer's dementia.

Materials and methods

We explored the age-related variability of cognitive and neuropsychological test scores in normal and accelerated aging and constructed regression models predicting functional performance in cognitive tests from brain radiomics data. The models were trained on the three study cohorts from ADNI dataset-cognitively normal individuals, patients with MCI or dementia-separately. We also looked for significant correlations between cortical parcellation volumes and test scores in the cohorts to investigate neuroanatomical differences in relation to cognitive status. Finally, we worked out an approach for the classification of the examinees according to the pattern of structure-function associations into the cohorts of the cognitively normal elderly and patients with MCI or dementia.

Results

In the healthy population, the global cognitive functioning slightly changes with age. It also remains stable across the disease course in the majority of cases. In healthy adults and patients with MCI or dementia, the trendlines of performance in digit symbol substitution test and trail making test converge at the approximated point of 100 years of age. According to the SFA pattern, we distinguish three cohorts: the cognitively normal elderly, patients with MCI, and dementia. The highest accuracy is achieved with the model trained to predict the mini-mental state examination score from voxel-based morphometry data. The application of the majority voting technique to models predicting results in cognitive tests improved the classification performance up to 91.95% true positive rate for healthy participants, 86.21%-for MCI and 80.18%-for dementia cases.

Conclusion

The machine learning model, when trained on the cases of this of that group, describes a disease-specific SFA pattern. The pattern serves as a "stamp" of the disease reflected by the model.

Performance Comparisons on the Saint Louis University Mental Status Examination Between Black and White Veterans and Education Classification in a Large Outpatient Sample from the Southern United States

Objective

An increasing scientific literature recognizes that traditional cut-off scores for cognitive screeners may not be optimal for use in patients who differ in race/ethnicity from the screeners’ normative/reference group. There is also literature on how racial/ethnic contextual factors, such as stereotype threat or perceived discrimination, may influence performance on cognitive testing. The current study examined the characteristics of SLUMS (a cognitive screening measure) performance in a large (n = 602) sample of Black (n = 229) and White (n = 373) veterans in a VA hospital located in the Southern United States.

Method

SLUMS data were gathered from retrospective electronic chart review between January 2013 and February 2020. Race/ethnicity of veterans was gathered by chart review and race of hospital providers who administered the SLUMS by personal communication.

Results

Black veterans were 1.99 times more likely to be classified by total SLUMS score as being within the dementia range compared with White veterans. Differences in item level performance were only found between Black and White veterans with ≥ high school education. Race of clinical provider (i.e., Black or White) administering the SLUMS did not significantly impact veteran performance on the SLUMS.

Conclusion

This is the first large sample study of differences in SLUMS performance between Black and White veterans. Findings replicate earlier research on Black and White performance differences on individual SLUMS items and provide an analysis of examiner–examinee racial discordance. This study underscores the importance of researching cognitive measures in groups who differ from the original normative/references samples.

Improvements in Cognitive Performance With Computerized Training in Older People With and Without Cognitive Impairment: Synergistic Effects of Skills-Focused and Cognitive-Focused Strategies

OBJECTIVES

Both cognitively impaired (CI) and nonimpaired (NC) older people have challenges in performing everyday tasks. Previous skills training efforts in NC individuals have led to improvements in both functional skills and cognitive functioning. We evaluated the cognitive benefits of combining computerized cognitive training (CCT) with a computer-based functional skills assessment and training (CFSAT) program in a sample of CI and NC older adults.

DESIGN

Randomized parallel clinical trial with two treatment conditions: up to 24 sessions of CFSAT training alone or CFSAT plus speed focused CCT.

PARTICIPANTS

NC (n = 62) and CI (n = 55) older adults, ranging in age from 60-86 years (M = 73.12), primarily female (90%), and ethnically diverse (21% Hispanic, 52% African American). Participants were divided based on Montreal Cognitive Assessment scores and cognitive complaints.

SETTING

Three different community centers in Miami, FL.

MEASUREMENTS

The Brief Assessment of Cognition, app version, was used to measure cognitive performance across six different cognitive domains before and after training.

RESULTS

All six cognitive domains improved from baseline. Multivariate analyses found the effects of the combined CFSAT and CCT to be superior. The interaction of training condition and cognitive status was not statistically significant, indicating no global impact of cognitive status on improvements in cognition across training conditions.

CONCLUSIONS

CFSAT training was associated with cognitive benefits, particularly in CI participants. The combined intervention led to greater improvements. Consistent with results of previous studies, there is considerable evidence of cognitive plasticity in older adults, including those with CI.

Systematic Review of the Psychometric Properties of the Saint Louis University Mental Status (SLUMS) Examination

OBJECTIVES

This systemic review qualitatively synthesizes existing psychometric support for the Saint Louis University Mental Status (SLUMS) Examination, a cognitive screening measure which presents as a free alternative to other widely used dementia screening measures including the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA).

METHODS

A total of 90 peer-reviewed articles on the SLUMS were identified from PsycINFO and PubMed databases.

RESULTS

Sixty-eight records were identified and reviewed by the lead author for eligibility. Studies that included at least one psychometric property of the SLUMS (n = 20) were included in this review.

CONCLUSIONS

Support for the SLUMS remains preliminary; however, it appears to have adequate validity, and adequate sensitivity and specificity in detecting cognitive impairment. Numerous shortcomings were identified, including lack of sufficient normative data, information on test-reliability, explored factor structure, and limited application of criterion measures (e.g., imaging studies, biomarkers). Research is needed to establish diverse normative samples and describe the reliability and validity of the SLUMS to strengthen the empirical support for its use.

CLINICAL IMPLICATIONS

Until its psychometric properties are better established the SLUMS should be used cautiously when screening for cognitive impairment.

Montreal Cognitive Assessment: Seeking a Single Cutoff Score May Not Be Optimal

Background

Cutoff scores of the Montreal cognitive assessment (MoCA) for screening mild cognitive impairment in older adults differ across the world and within the Chinese culture. It is argued that to seek a cutoff score is essential to classify test participants. It was unknown how taking a classifying approach might reveal the cutoff score for identifying mildly cognitively impaired older adults.

Methods

Participants, selected from 13 communities in Wuhan, China, were tested with the Chinese version of MoCA and rated with the Activities of Daily Living and the Clinical Dementia Rating scales. Mixture modeling was applied to the data with certain covariates and MoCA sum scores as the outcome of the latent class. Models with different numbers of classes were compared in terms of information criteria, likelihood ratio test, entropy, and interpretability.

Results

A 3-class model (normal, mildly impaired, and severely impaired) was found to fit the data best. The normal class averaged a MoCA score of 24, while the severely impaired class averaged a score below 18. For those cases with MoCA scores above 18 and below 24, it is not certain if they are in the normal or the severely impaired classes.

Conclusion

Latent variable classification modeling provides another option to identify MCI in older adults. Some categorically different cases of MCI cannot be captured with any single MoCA sum score. A range of 18–24 MoCA scores might serve as a better screening criterion of MCI. Older adults who scored within this gray zone should be monitored for potential interventions.

Perceived Stress is Associated with Alzheimer's Disease Cerebrospinal Fluid Biomarkers in African Americans with Mild Cognitive Impairment

BACKGROUND

African Americans (AA) have a higher Alzheimer's disease (AD) prevalence and report more perceived stress than White Americans. The biological basis of the stress-AD link is unclear. This study investigates the connection between stress and AD biomarkers in a biracial cohort.

OBJECTIVE

Establish biomarker evidence for the observed association between stress and AD, especially in AA.

METHODS

A cross-sectional study (n = 364, 41.8% AA) administering cognitive tests and the perceived stress scale (PSS) questionnaire. A subset (n = 309) provided cerebrospinal fluid for measurement of Aβ42, Tau, Ptau, Tau/Aβ42 (TAR), and Ptau/Aβ42 (PTAR). Multivariate linear regression, including factors that confound racial differences in AD, was performed.

RESULTS

Higher PSS scores were associated with higher Ptau (β= 0.43, p = 0.01) and PTAR (β= 0.005, p = 0.03) in AA with impaired cognition (mild cognitive impairment).

CONCLUSION

Higher PSS scores were associated with Tau-related AD biomarker indices in AA/MCI, suggesting a potential biological connection for stress with AD and its racial disparity.

Reporting of Demographic Variables in Neuropsychological Research: An Update of O'Bryant et al.'s Trends in the Current Literature

OBJECTIVE

Demographic trends and the globalization of neuropsychology have led to a push toward inclusivity and diversity in neuropsychological research in order to maintain relevance in the healthcare marketplace. However, in a review of neuropsychological journals, O'Bryant et al. found systematic under-reporting of sample characteristics vital for understanding the generalizability of research findings. We sought to update and expand the findings reported by O'Bryant et al.

METHOD

We evaluated 1648 journal articles published between 2016 and 2019 from 7 neuropsychological journals. Of these, 1277 were original research or secondary analyses and were examined further. Articles were coded for reporting of age, sex/gender, years of education, ethnicity/race, socioeconomic status (SES), language, and acculturation. Additionally, we recorded information related to sample size, country, and whether the article focused on a pediatric or adult sample.

RESULTS

Key variables such as age and sex/gender (both over 95%) as well as education (71%) were frequently reported. Language (20%) and race/ethnicity (36%) were modestly reported, and SES (13%), and acculturation (<1%) were more rarely reported. SES was more commonly reported in pediatric than adult samples, and the opposite was true for education. There were differences between the present results and those of O'Bryant et al., though the same general trends remained.

CONCLUSIONS

Reporting of demographic data in neuropsychological research appears to be slowly changing toward greater comprehensiveness, though clearly more work is needed. Greater systematic reporting of such data is likely to be beneficial for the generalizability and contextualization of neurocognitive function.

Accuracy of the Montreal Cognitive Assessment in Detecting Mild Cognitive Impairment and Dementia in the Rural African Population

OBJECTIVE

The incidence of dementia in the sub-Saharan Africa is rising. However, screening tools for cognitive decline that fits their linguistic and cultural context are lacking. The aim of this study was to determine the accuracy of the Kiswahili version of Montreal Cognitive Assessment (K-MoCA) to detect mild cognitive impairment or dementia among older adults in the rural Tanzania.

METHODS

We recruited 259 community-dwelling older adults in Chamwino district, Tanzania. The concurrent validity and discriminatory power of K-MoCA were examined by comparing its score with IDEA cognitive screening and psychiatrist's diagnosis using DSM-V, respectively. All the questionnaires were administered in face-to-face interview.

RESULTS

K-MoCA demonstrated acceptable reliability (Cronbach's alpha = 0.780). Concurrent validity was evident by its significant correlation with the IDEA screening test (Pearson's r = 0.651, p < 0.001). Using the psychiatrist's rating as the reference, the optimal cut-off score for MCI and dementia was 19 and 15, respectively, which yielded the sensitivity of 70% and specificity of 60% for MCI, and sensitivity of 72% and specificity of 60% for dementia. Further analysis indicated that education and age influence performance on K-MoCA.

CONCLUSION

Overall, the K-MoCA is a reliable and valid tool for measuring cognitive decline. However, its limited discriminatory power for MCI and dementia may be compromised by the cultural irrelevance of some items.

Differentiating among stages of cognitive impairment in aging: Version 3 of the Uniform Data Set (UDS) neuropsychological test battery and MoCA index scores

INTRODUCTION

Federally funded Alzheimer's Disease Centers in the United States have been using a standardized neuropsychological test battery as part of the National Alzheimer's Coordinating Center Uniform Data Set (UDS) since 2005. Version 3 (V3) of the UDS replaced the previous version (V2) in 2015. We compared V2 and V3 neuropsychological tests with respect to their ability to distinguish among the Clinical Dementia Rating (CDR) global scores of 0, 0.5, and 1.

METHODS

First, we matched participants receiving V2 tests (V2 cohort) and V3 tests (V3 cohort) in their cognitive functions using tests common to both versions. Then, we compared receiver-operating characteristic (ROC) area under the curve in differentiating CDRs for the remaining tests.

RESULTS

Some V3 tests performed better than V2 tests in differentiating between CDR 0.5 and 0, but the improvement was limited to Caucasian participants.

DISCUSSION

Further efforts to improve the ability for early identification of cognitive decline among diverse racial groups are required.

Application of neuropsychological criteria to classify mild cognitive impairment in the active study

Objective: Comprehensive neuropsychological criteria (NP criteria) for mild cognitive impairment (MCI) has reduced diagnostic errors and better predicted progression to dementia than conventional MCI criteria that rely on a single impaired score and/or subjective report. This study aimed to implement an actuarial approach to classifying MCI in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study. Method: ACTIVE study participants (N = 2,755) were classified as cognitively normal (CN) or as having MCI using NP criteria. Estimated proportion of MCI participants and reversion rates were examined as well as baseline characteristics by MCI subtype. Mixed effect models examined associations of MCI subtype with 10-year trajectories of self-reported independence and difficulty performing instrumental activities of daily living (IADLs). Results: The proportion of MCI participants was estimated to be 18.8%. Of those with MCI at baseline, 19.2% reverted to CN status for all subsequent visits. At baseline, the multidomain-amnestic MCI group generally had the greatest breadth and depth of cognitive impairment and reported the most IADL difficulty. Longitudinally, MCI participants showed faster IADL decline than CN participants (multidomain-amnestic MCI > single domain-amnestic MCI > nonamnestic MCI). Conclusion: NP criteria identified a proportion of MCI and reversion rate within ACTIVE that is consistent with prior studies involving community-dwelling samples. The pattern of everyday functioning change suggests that being classified as MCI, particularly amnestic MCI, is predictive of future loss of independence. Future work will apply these classifications in ACTIVE to better understand the relationships between MCI and health, social, and cognitive intervention-related factors. (PsycInfo Database Record (c) 2020 APA, all rights reserved).