Predictors of future cognitive decline in persons with mild cognitive impairment

Predictive Models for the Transition from Mild Neurocognitive Disorder to Major Neurocognitive Disorder: Insights from Clinical, Demographic, and Neuropsychological Data

Neurocognitive disorders (NCDs) are progressive conditions that severely impact cognitive function and daily living. Understanding the transition from mild to major NCD is crucial for personalized early intervention and effective management. Predictive models incorporating demographic variables, clinical data, and scores on neuropsychological and emotional tests can significantly enhance early detection and intervention strategies in primary healthcare settings. We aimed to develop and validate predictive models for the progression from mild NCD to major NCD using demographic, clinical, and neuropsychological data from 132 participants over a two-year period. Generalized Estimating Equations were employed for data analysis. Our final model achieved an accuracy of 83.7%. A higher body mass index and alcohol drinking increased the risk of progression from mild NCD to major NCD, while female sex, higher praxis abilities, and a higher score on the Geriatric Depression Scale reduced the risk. Here, we show that integrating multiple factors-ones that can be easily examined in clinical settings-into predictive models can improve early diagnosis of major NCD. This approach could facilitate timely interventions, potentially mitigating the progression of cognitive decline and improving patient outcomes in primary healthcare settings. Further research should focus on validating these models across diverse populations and exploring their implementation in various clinical contexts.

Association between walking speed and cognitive domain functions in Chinese suburban-dwelling older adults

Objective

To examine the relationship among walking speed, cognitive impairment, and cognitive domain functions in older men and women living in a Chinese suburban community.

Methods

In total, 625 elderly (72.54 ± 5.80 years old) men (n = 258) and women (n = 367) from the Chongming district of Shanghai participated in this study. All participants had Mini-Mental State Examination (MMSE), 4-m walking test, medical history questionnaire, and physical examination. They were grouped according to walking speed (>0.8 vs. ≤ 0.8 m/s) with the stratification of sex. The odds ratio (OR) and the 95% confidence interval (CI) were assessed using the chi-square test and logistic regression analysis.

Results

Around 11.6% of men and 14.2% of women had slow walking speeds. After adjusting for age, body mass index (BMI), education level, spouse, faller, the Geriatric Depression Scale (GDS) score, heart disease, stroke, arthritis, and low back pain, walking speed was negatively related to cognitive impairment in men (OR 0.11 [95% CI: 0.01, 0.94]; p = 0.043). In addition, the relationship between walking speed and impaired orientation was significant in both men (OR 0.003 [95% CI: 0.001, 0.05]; p < 0.001) and women (OR 0.15 [95% CI: 0.03, 0.75]; p = 0.021).

Conclusion

The relationship between walking speed and cognitive impairment was only significant in men, but the association with impaired orientation was found in both men and women. Assessing the walking speed of the elderly is beneficial, which may help with early detection and early therapeutic prevention of cognitive impairment.

The extra costs associated with a cognitive impairment: Estimates from 15 OECD countries

BACKGROUND

The objective of this study is to estimate the additional income required of a household containing an older adult member living with a cognitive impairment (CI) consistent with dementia (CID).

METHODS

Secondary analyses were provided of data from the Survey of Health Aging and Retirement in Europe incorporating data of adults' age 65 years old and older across 15 OECD countries in 2013. We also analyzed longitudinal data of a smaller subset of respondents interviewed in a previous survey wave in 2011. We used OLS regression and the Standard of Living (SOL) approach to estimating the extra costs of disability.

RESULTS

Households containing a member experiencing a CID are estimated to require 48% more income to maintain their SOL compared to similar households not including an adult with CID. Those with CI without dementia are estimated to have lower costs (14%). Those with longer-term CID are estimated to incur greater costs than those with a more recent onset of a CI. The extra costs are estimated to be lower in countries with more formalized public long-term care arrangements. We further identified out of pocket costs for home care services as a likely expenditure item driving these cost estimates.

CONCLUSIONS

Results suggest that caring for a person living with dementia can lead to considerable expenses. These additional direct costs associated with dementia provide insights for households in anticipating the risks of financial insecurity as they grow older. Future research is needed to identify the consumption items driving these estimates.

Benefits of VR Physical Exercise on Cognition in Older Adults with and without Mild Cognitive Decline: A Systematic Review of Randomized Controlled Trials

It is well known that physical exercise has beneficial effects on cognitive function in older adults. Recently, several physical exercise programs with virtual reality (VR) have been proposed to support physical exercise benefits. However, it is still unclear whether VR physical exercise (VR-PE) has positive effects on cognitive function in older adults. The purpose of this study was to conduct a systematic review (SR) of the effects of VR-PE on cognitive function in older adults with and without cognitive decline. We used academic databases to search for research papers. The criteria were intervention study using any VR-PE, participants were older adults with and without mild cognitive decline (not dementia), and cognitive functions were assessed. We found that 6 of 11 eligible studies reported the significant benefits of the VR-PE on a wide range of cognitive functions in aging populations. The SR revealed that VR-PE has beneficial effects on the inhibition of executive functions in older adults with and without mild cognitive decline. Moreover, VR-PE selectively leads to improvements in shifting and general cognitive performance in healthy older adults. The SR suggests that VR-PE could be a successful approach to improve cognitive function in older adults with and without cognitive decline.

Usefulness of CogEvo, a computerized cognitive assessment and training tool, for distinguishing patients with mild Alzheimer's disease and mild cognitive impairment from cognitively normal older people

AIM

This study aimed to assess whether CogEvo, a computerized cognitive assessment and training tool, could distinguish patients with mild Alzheimer's disease and mild cognitive impairment from cognitively normal older people.

METHODS

This cross-sectional study enrolled 166 participants with Alzheimer's disease, mild cognitive impairment and cognitively normal older people. In CogEvo, five types of cognitive tasks were carried out, and the z-scores were used as a composite score. Logistic regression and receiver operating characteristics analyses were then carried out to evaluate the usefulness of CogEvo in distinguishing between the three groups.

RESULTS

CogEvo and Mini-Mental State Examination scores showed excellent correlation, and could significantly differentiate between the Alzheimer's disease, mild cognitive impairment and cognitively normal older people groups (Mini-Mental State Examination 20.4 ± 3.5, 25.5 ± 1.6 and 27.6 ± 2.0, respectively; CogEvo: -1.9 ± 0.9, -0.8 ± 0.8 and 0.0 ± 1.0, respectively; both P < 0.001 by analysis of variance). Logistic regression analysis adjusted for age, sex and years of education significantly differentiated the mild cognitive dysfunction group (mild cognitive impairment plus mild Alzheimer's disease; n = 78) from the cognitively normal group (n = 88) (P < 0.001), whereas receiver operating characteristics analysis showed moderate accuracy (area under the receiver operating characteristic curve 0.830).

CONCLUSIONS

These results suggest that CogEvo, a computerized cognitive assessment tool, is useful for evaluating early-stage cognitive impairment. Further studies are required to assess its effectiveness as a combination assessment and training tool. Geriatr Gerontol Int 2021; 21: 192-196.

Evaluating the Real-World Representativeness of Participants with Mild Cognitive Impairment in Canadian Research Protocols: a Comparison of the Characteristics of a Memory Clinic Patients and Research Samples

Background

Studies of mild cognitive impairment (MCI) employ rigorous eligibility criteria, resulting in sampling that may not be representative of the broader clinical population.

Objective

To compare the characteristics of MCI patients in a Calgary memory clinic to those of MCI participants in published Canadian studies.

Methods

Clinic participants included 555 MCI patients from the PROspective Registry of Persons with Memory SyMPToms (PROMPT) registry in Calgary. Research participants included 4,981 individuals with MCI pooled from a systematic literature review of 112 original, English-language peer-reviewed Canadian studies. Both samples were compared on baseline sociodemographic variables, medical and psychiatric comorbidities, and cognitive performance for MCI due to Alzheimer’s disease and Parkinson’s disease.

Results

Overall, clinic patients tended to be younger, more often male, and more educated than research participants. Psychiatric disorders, traumatic brain injury, and sensory impairment were commonplace in PROMPT (up to 83% affected) but > 80% studies in the systematic review excluded these conditions. PROMPT patients also performed worse on global cognition measures than did research participants.

Conclusion

Stringent eligibility criteria in Canadian research studies excluded a considerable subset of MCI patients with comorbid medical or psychiatric conditions. This exclusion may contribute to differences in cognitive performance and outcomes compared to real-world clinical samples.

Predicting Cognitive Decline in Parkinson's Disease with Mild Cognitive Impairment: A One-Year Observational Study

We conducted an observational study to investigate clinical predictors of cognitive decline in patients with mild cognitive impairment (MCI), with a focus on patients with Parkinson's disease (PD) and Alzheimer's disease (AD). The study was performed with detailed neuropsychological testing, a portable device for gait analysis, and a comprehensive geriatric assessment for patients with MCI. Cognitive decline was defined as subjective cognitive impairment with an objective decline in the Mini-Mental State Examination (MMSE) ≥2 points at the one-year follow-up. Participants (n = 74) had a median age of 70 (interquartile range 60–79) years, and 45.9% of them were women. At the end of the study, 17.6% of the patients with MCI had a cognitive decline. Although no differences were observed between groups at the baseline cognitive study, patients with PD-MCI demonstrated more cognitive decline than patients with AD-MCI (28.6% vs. 7.7% p = 0.03). Patients with PD-MCI had more physical disabilities, including scores of instrumental activities of daily living (IADL), Tinetti balance, and gait scores, and some Timed Up and Go components. Initial Clinical Dementia Rating—Sum of Boxes score was a better predictor of future cognitive decline than MMSE in PD-MCI. For predicting the occurrence of cognitive decline in PD-MCI, the prediction accuracy increased from the reduced model (AUC = 0.822, p < 0.001) to the full model (a total of five independent variables, AUC = 0.974, p < 0.001). Given the potentially modifiable predictor, our findings also highlight the importance of identifying sleep quality and the ability to perform IADL.

Characteristics of decline in cognition and locomotion among the elderly in seven provinces of China

BACKGROUND

Decline in cognition and in locomotion is associated with aging. However, the relationship between them and the current occurrence of them in Chinese elderly people was weak.

METHODS

To investigate the details of these two functions in Chinese elderly people and to try to find some early recognition and intervention clues, data of MMSE test and usual gait speed from 4487 elderly people from seven provinces in China were analysed.

RESULTS

The prevalence of mild cognitive impairment (MCI) and dementia in persons aged 60 and over was 17.83% and 4.08%, respectively. Among 11 items of MMSE, calculation, three-word recall, drawing two pentagons, and temporal orientation were the most commonly impaired items in persons with MCI or dementia. The gait speed of old persons with dementia was significantly slower than that of persons with MCI or NCI. Meanwhile, old persons with gait speed >1.39 m/s fast gait speed also had high MMSE scores and no dementia was detected by MMSE.

CONCLUSION

The prevalence of dementia observed in this population was similar to that reported 20 years ago. Loss of temporal orientation and drawing two pentagons may supply more information for early recognition of cognitive impairment. Maintaining locomotion in a proper way may help old persons to prevent cognitive function decline.

Sarcopenia Is Associated with Cognitive Impairment Mainly Due to Slow Gait Speed: Results from the Korean Frailty and Aging Cohort Study (KFACS)

Sarcopenia and cognitive impairment may share common risk factors and pathophysiological pathways. We examined the association between impairments in specific cognitive domains and sarcopenia (and its defining components) in community-dwelling older adults. We analyzed 1887 patients who underwent cognitive function tests and dual-energy X-ray absorptiometry from the baseline data of adults aged 70-84 years obtained from the Korean Frailty and Aging Cohort Study. Those with disability in activities of daily living, dementia, severe cognitive impairment, Parkinson's disease, musculoskeletal complaints, neurological disorders, or who were illiterate were excluded. Cognitive function was assessed using the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet, the Frontal Assessment Battery. For sarcopenia, we used the diagnostic criteria of the Asian Working Group for Sarcopenia. The prevalence of sarcopenia was 9.6% for men and 7.6% for women. Sarcopenia (odds ratio [OR] 1.76, 95% confidence interval [CI] 1.04-2.99) and slow gait speed (OR 2.58, 95% CI 1.34-4.99) were associated with cognitive impairment in men. Only slow gait speed (OR 1.88, 95% CI 1.05-3.36) was associated with cognitive impairment in women. Sarcopenia is associated with cognitive impairment mainly due to slow gait speed. Our results suggested that cognitive impairment domains, such as processing speed and executive function, are associated with sarcopenia-related slow gait speed.

Personalized Risk Index for Neurocognitive Decline Among People With Well-Controlled HIV Infection

BACKGROUND

Little is known about the predictors of neurocognitive decline in HIV+ individuals with good virological control. Identification of modifiable risk factors would allow targeted interventions to reduce the risk of decline in higher risk individuals. The objective of this study was to develop a risk index to predict neurocognitive decline over 3 years in aviremic HIV+ individuals.

METHODS

As part of the CNS HIV Anti-Retroviral Therapy Effects Research (CHARTER) study, HIV+ adults completed clinical evaluation and neuropsychological tests every 6 months. Group-based trajectory analysis was used to detect patterns of neurocognitive change; individuals who deteriorated ≥ 0.5 SD on at least one neuropsychological test were considered decliners. Multiple logistic regression was used to identify baseline sociodemographic, clinical, biological, and lifestyle factors associated with decline in the subgroup that was consistently aviremic during the first 3 years. A risk index was developed using the beta-coefficients from the final regression model.

RESULTS

Neurocognitive decline occurred in 23 of 191 (12%) participants followed longitudinally. The baseline factors that predicted decline were glomerular filtration rate ≤50 mL/min, known duration of HIV infection ≥15 years, education ≤12 years, and cerebrospinal fluid protein >45 mg/dL.

CONCLUSIONS

Using this analytic approach, neurocognitive decline was uncommon in this sample of aviremic HIV+ individuals. The 3-year risk of decline ranged from 2% in those with no risk factors to 95% in those with all 4. The strongest predictor was glomerular filtration rate, also a predictor of cardiovascular disease. This raises the possibility that controlling vascular risk factors could reduce the risk of neurocognitive decline.

Psychometric Properties of the Persian Adaptation of Mini-Cog Test in Iranian Older Adults

The aim of this study was to assess the psychometric properties of the Mini-Cog in Iranian older adults. It was a cross-sectional study; 50 older people with dementia and 50 without dementia who matched for age, gender, and education entered the study. The diagnostic and statistical manual of mental disorders criteria for dementia were used as gold standard. A battery of scales included the abbreviated mental test score (AMTS), the Geriatric Depression Scale, and the Mini-Cog was performed. Validity and reliability of the Mini-Cog determined using the Pearson product-moment correlation coefficient (Pearson's r), Cronbach's alpha, and Receiver Operating Characteristic (ROC) curve analysis. The Persian version of Mini-Cog showed a good inter-rater reliability ( K = 0.76, p < .01) and a positive concurrent validity ( r = 0.39, p < .01) with the AMTS. The sensitivity and specificity were 88% and 62.8%, respectively, using the original cutoff point of 2. The findings showed that the Persian version of Mini-Cog have an acceptable sensitivity, specificity, and substantial overall agreement with the AMTS.

Delayed Recall and Working Memory MMSE Domains Predict Delirium following Cardiac Surgery

BACKGROUND

Reduced preoperative cognition is a risk factor for postoperative delirium. The significance for type of preoperative cognitive deficit, however, has yet to be explored and could provide important insights into mechanisms and prediction of delirium.

OBJECTIVE

Our goal was to determine if certain cognitive domains from the general cognitive screener, the Mini-Mental State Exam (MMSE), predict delirium after cardiac surgery.

METHODS

Patients completed a preoperative MMSE prior to undergoing elective cardiac surgery. Following surgery, delirium was assessed throughout ICU stay using the Confusion Assessment Method for ICU delirium and the Richmond Agitation and Sedation Scale.

RESULTS

Cardiac surgery patients who developed delirium (n = 137) had lower total MMSE scores than patients who did not develop delirium (n = 457). In particular, orientation to place, working memory, delayed recall, and language domain scores were lower. Of these, only the working memory and delayed recall domains predicted delirium in a regression model adjusting for history of chronic obstructive pulmonary disease, age, sex, and duration of cardiopulmonary bypass. For each word not recalled on the three-word delayed recall assessment, the odds of delirium increased by 50%. For each item missed on the working memory index, the odds of delirium increased by 36%. Of the patients who developed delirium, 47% had a primary impairment in memory, 21% in working memory, and 33% in both domains. The area under the receiver operating characteristics curve using only the working memory and delayed recall domains was 0.75, compared to 0.76 for total MMSE score.

CONCLUSION

Delirium risk is greater for individuals with reduced MMSE scores on the delayed recall and working memory domains. Research should address why patients with memory and executive vulnerabilities are more prone to postoperative delirium than those with other cognitive limitations.

Approaches in methodology for population-based longitudinal study on neuroprotective model for healthy longevity (TUA) among Malaysian Older Adults

A number of longitudinal studies on aging have been designed to determine the predictors of healthy longevity, including the neuroprotective factors, however, relatively few studies included a wide range of factors and highlighted the challenges faced during data collection. Thus, the longitudinal study on neuroprotective model for healthy longevity (LRGS TUA) has been designed to prospectively investigate the magnitude of cognitive decline and its risk factors through a comprehensive multidimensional assessment comprising of biophysical health, auditory and visual function, nutrition and dietary pattern and psychosocial aspects. At baseline, subjects were interviewed for their status on sociodemographic, health, neuropsychological test, psychosocial and dietary intake. Subjects were also measured for anthropometric and physical function and fitness. Biospecimens including blood, buccal swap, hair and toenail were collected, processed and stored. A subsample was assessed for sensory function, i.e., vision and auditory. During follow-up, at 18 and 36 months, most of the measurements, along with morbidity and mortality outcomes will be collected. The description of mild cognitive impairment, successful aging and usual aging process is presented here. A total 2322 respondents were recruited in the data analysis at baseline. Most of the respondents were categorized as experiencing usual aging (73 %), followed by successful aging (11 %) and mild cognitive impairment (16 %). The LRGS TUA study is the most comprehensive longitudinal study on aging in Malaysia, and will contribute to the understanding of the aging process and factors associated with healthy aging and mental well-being of a multiethnic population in Malaysia.

Prognostic Significance of Mild Cognitive Impairment Subtypes for Dementia and Mortality: Data from the NEDICES Cohort

BACKGROUND

The predictive value of diverse subtypes of mild cognitive impairment (MCI) for dementia and death is highly variable.

OBJECTIVE

To compare the predictive value of several MCI subtypes in progression to dementia and/or mortality in the NEDICES (Neurological Disorders in Central Spain) elderly cohort.

METHODS

Retrospect algorithmic MCI subgroups were established in a non-dementia baseline NEDICES cohort using Spanish adaptations of the original Mini-Mental State Examination (MMSE-37) and Pfeffer's Functional Activities Questionnaire (Pfeffer-11). The presence of MCI was defined according two cognitive criteria: using two cut-offs points on the total MMSE-37 score. Five cognitive domains were used to establish the MCI subtypes. Functional capacity (Pfeffer-11) was preserved or minimally impaired in all MCI participants. The incident dementia diagnoses were established by specialists and the mortality data obtained from Spanish official registries.

RESULTS

3,411 participants without dementia were assessed in 1994-5. The baseline prevalence of MCI varied according to the MCI definition (4.3%-31.8%). The follow-up was a mean of 3.2 years (1997-8). The dementia incidence varied between 14.9 and 71.8 per 1,000/person-years. The dementia conversion rate was increased in almost all MCI subgroups (p >  0.01), and mortality rate was raised only in four MCI subtypes. The amnestic-multi-domain MCI (aMd-MCI) had the best dementia predictive accuracy (highest positive likelihood ratio and highest clinical utility when negative).

CONCLUSIONS

Those with aMd-MCI were at greatest risk of progression to dementia, as in other surveys and might be explored with increased attention in MCI research and in dementia preventive trials.

Accuracy of a Brief Neuropsychological Battery for the Diagnosis of Dementia and Mild Cognitive Impairment: An Analysis of the NEDICES Cohort

Early separation of mild cognitive impairment (MCI) from normal aging and mild cases of dementia remains a challenge, especially in the general population. We aimed to analyze the diagnostic accuracy of a brief neuropsychological battery (BNB) in dementia and MCI cases from the Neurological Disorders in Central Spain (NEDICES) population-based cohort study. We screened 3,891 participants into dementia and non-dementia groups using a two-phase procedure: screening (MMSE-37 and Pfeffer-11) and clinical diagnosis by specialists (DSM-IV criteria). We selected subsequently a subsample of dementia (n = 98), MCI (n = 71), and cognitively healthy (n = 123) participants matched in socio-demographic characteristics. The clinical validity of each test of the BNB was determined by the area under the ROC curve. We determined the best combination of tests to classify individuals into the diagnostic groups by logistic regression analyses. The results indicated that dementia and MCI groups could be best discriminated from the healthy control group on the basis of their scores on the semantic verbal fluency and delayed recall subtests of the BNB. As for discriminating the MCI group from the dementia group, immediate recall tasks (stories and pictures) yielded the highest level of accuracy. Probably the most interesting finding is that the verbal fluency task consistently allowed discrimination among the diagnostic groups. Overall, subtests of the BNB are more accurate in differentiating dementia patients than MCI patients from healthy controls. In this population-based sample, a more fine-grained discrimination that includes MCI patients should follow a systematic subtest-wise analysis and decision.

Cognitive Test Performance in Relation to Health and Function in 12 European Countries: The SHARE Study

Background

Even subtle impairments on cognitive test scores can be associated with future cognitive decline and dementia. We assayed the relationships between test score impairment and adverse outcomes.

Methods

Secondary analyses were performed on data from non-institutionalized participants, 50+ years of age (N = 30,038), from 12 countries taking part in the Survey of Health, Ageing and Retirement in Europe (SHARE) longitudinal study on aging. At baseline, participants’ cognition was tested using verbal fluency, immediate recall, and delayed recall tasks.

Results

Greater levels of cognitive impairment at baseline were strongly associated with future poor health outcomes and functional impairment. Controlling for age, sex and education, those with 1 (OR = 1.58, 95% CI = 1.34–1.87) or ≥ 2 (OR = 2.59, 95% CI = 2.17–3.09) impaired tests at baseline were more likely to die after an average of 40 months compared to individuals with no impairments. After selecting for participants who reported the absence of dementia initially, those with ≥ 2 cognitive impairments at baseline (OR = 3.34, 95% CI = 2.27–4.92) were more likely to report dementia at follow-up compared to those with no impairment.

Conclusions

People with impaired cognitive test scores at baseline are at greater risk to die or develop dementia within four years than their less impaired or unimpaired counterparts.

Clustering mild cognitive impairment by mini-mental state examination

We aimed to evaluate whether the performance of the mini-mental state examination (MMSE) could identify risky mild cognitive impairment (MCI). We recruited 122 amnestic MCI-single domain (ASM), 303 amnestic MCI-multiple domains (AMM), and 94 non-amnestic MCI (NAM). Two-step cluster and linear discriminant analyses were used for identifying the clusters of the MMSE with age and education, as well as establishing prediction models for each cluster. Conversion into dementia was compared among clusters. Cluster analyses revealed the following three: cluster 1 = 205 AMM (100 %); cluster 2 = 61 NAM (33.3 %) and 122 ASM (66.7 %); and cluster 3 = 33 NAM (25.2 %) and 98 AMM (74.8 %). Cluster 3 showed a significantly lower ability with regards to orientation to time and place, registration of three words, attention/calculation, language, and copying interlocking pentagons, than clusters 1 and 2. However, for delayed recall, cluster 1 was significantly more impaired than cluster 2. Patients in the cluster 1 showed the most common conversion into dementia [odds ratio (OR) = 2.940 vs. cluster 2, OR = 2.271 vs. cluster 3]. This study showed that clustering by performance in MMSE could help define groups at higher risk for conversion to dementia. Therefore, MMSE can be considered as a promising screening tool including subtyping for MCI when detailed neuropsychological tests are not feasible.

Cognitive impairment with and without depression history: an analysis of white matter microstructure

BACKGROUND

Mild cognitive impairment (MCI) and late-life depression are clinical syndromes that often co-occur and may represent an early manifestation of neurodegenerative disease. The present study examined white matter microstructure in patients with MCI with and without a history of major depression compared with healthy controls.

METHODS

Older adults with MCI and no history of major depression (MCI), adults with MCI and euthymic major depression (MCI-MD) and healthy controls underwent comprehensive medical, psychiatric and neuropsychological assessments. Participants also underwent diffusion tensor imaging, which was analyzed using tract-based spatial statistics. White matter hyperintensity (WMH) burden and medical burden were also quantified.

RESULTS

We enrolled 30 participants in the MCI group, 36 in the MCI-MD group and 22 in the control group. Compared with controls, participants in the MCI group had significantly reduced fractional anisotropy (FA) in the corpus callosum, superior longitudinal fasciculus (SLF), corona radiata and posterior thalamic radiation. Participants in the MCI-MD group had significantly reduced FA in the corpus callosum, internal capsule, external capsule, corona radiata, posterior thalamic radiation, sagittal striatum, fornix, SLF, uncinate fasciculus and right cingulum compared with controls. No significant differences in FA were observed between the MCI and MCI-MD groups. Participants in the MCI-MD group had greater medical burden (p = 0.020) and WMH burden than controls (p = 0.013).

LIMITATIONS

Study limitations include the cross-sectional design and antidepressant medication use.

CONCLUSION

To our knowledge, this study is the first to compare white matter microstructure in patients with MCI with and without a history of major depression and suggests that a common underlying structural white matter change may underpin cognitive impairment in both MCI groups. Further research is needed to delineate the pathophysiological mechanisms underlying these microstructural changes.

Limitations for interpreting failure on individual subtests of the Montreal Cognitive Assessment

BACKGROUND

The Montreal Cognitive Assessment (MoCA) is sensitive to mild forms of cognitive impairment in geriatric populations and asks questions under the subheadings visuospatial/executive, naming, attention, language, abstraction, delayed recall, and orientation. This study examined the extent to which these subsets of MoCA items evaluate their intended cognitive domains.

METHODS

Clinical data from 185 geriatric memory clinic outpatients who underwent cognitive screening and subsequent neuropsychological assessment were analyzed. Factor analysis of their neuropsychological test scores identified 5 cognitive domains memory, language, visuospatial ability, attention/processing speed, and cognitive control. Scores on MoCA subtests were examined for their correlations with individual factor scores and for their sensitivity and specificity in predicting impairment within each domain.

RESULTS

The MoCA subtest scores correlated significantly but modestly with neuropsychological test factor scores in their corresponding domains, for example, the correlation between 5-word recall and the memory factor was 0.46. However, subtest scores were poor predictors of impaired performance on the tests contributing to each cognitive domain. The best predictive accuracy was seen for the visuospatial/executive subtest that showed fair accuracy at predicting impairment on tests in the visuospatial domain. Other subtests showed unacceptably poor levels of accuracy when predicting impaired scores in their respective domains (60%-67%).

CONCLUSIONS

In a sample of geriatric outpatients referred for cognitive assessment, performance on individual items and subtests of the MoCA yields insufficient information to draw conclusions about impairment in specific cognitive domains as determined by neuropsychological testing.

DAD-6: A 6-ltem version of the Disability Assessment for Dementia scale which may differentiate Alzheimer's disease and mild cognitive impairment from controls

BACKGROUND

The need to detect early changes in instrumental activities of daily life led us to modify the Disability Assessment for Dementia Scale (DAD) by focusing on executive components of 6 instrumental items (DAD-6).

AIM

To evaluate the relevance of the DAD-6 for detecting early impairment in a nondemented population.

METHODS

The DAD-6 was administered to informants of 84 patients: 31 with mild dementia (MD), 53 with mild cognitive impairment (MCI) and 55 healthy controls.

RESULTS

DAD-6 scores gradually decreased with increasing severity of the cognitive status [18 in healthy controls vs. 15.1 ± 3.2 in MCI versus 9.6 ± 3.5 in MD, p < 0.0001). Receiver-operating characteristic curve analyses yielded an optimal cut score of 14 to distinguish MCI from MD with a sensitivity of 0.83 (95% confidence interval 0.74-0.92) and a specificity of 0.84 (0.71-0.94), and a cut score of 15 to distinguish single-domain MCI from multi-domain MCI with a sensitivity of 0.96 (0.90-0.99) and a specificity of 0.54 (0.33-0.75).

CONCLUSION

The DAD-6 reliably detects early loss of autonomy due to cognitive impairment.

Mini-Cog and Mini-Mental State Examination: agreement in a cross-sectional study with an elderly sample

BACKGROUND/AIMS

We aimed to compare the Mini-Mental State Examination (MMSE) with the Mini-Cog, measuring agreement in participants' classification, using a general population sample.

METHODS

Cross-sectional evaluation of 609 community dwellers aged ≥60 years was performed by trained interviewers. Cohen's kappa and 95% confidence intervals (CI) were calculated to assess overall agreement, and Cronbach alphas computed to assess reliability. Two-parameter Item Response Theory models (difficulty and discrimination parameters) were used to assess discrimination.

RESULTS

Considering MMSE cut-point for scores <24, 3.1% of the participants would be 'cognitive impaired' and 6.2% considering cut-point scores <25. Following Mini-Cog's cut-point score <3, 11.3% would be impaired. For MMSE cut-point <24 and Mini-Cog <3, we observed a Cohen's kappa of 0.116 (95% CI: -0.073 to 0.305), and of 0.258 (95% CI: 0.101-0.415) for cut-point <25. The highest kappa was obtained for cut-point <26 on the MMSE and Mini-Cog <3 (kappa = 0.413). MMSE Cronbach alpha was 0.6108 and Mini-Cog's alpha was 0.2776. Co-calibration according to inherent ability is graphically presented.

CONCLUSIONS

Agreement between scales seems fragile in our sample. The discriminative and reliability analysis suggests a better performance for subsets of the MMSE compared with the Mini-Cog. Usefulness of calibrated scores is discussed.