Predictors of Reversion from Mild Cognitive Impairment to Normal Cognition

Predicting the reversion from mild cognitive impairment to normal cognition based on magnetic resonance imaging, clinical, and neuropsychological examinations

BACKGROUND

Reversion from mild cognitive impairment (MCI) to normal cognition (NC) is not uncommon and indicates a better cognitive trajectory. This study aims to identify predictors of MCI reversion and develop a predicting model.

METHOD

A total of 391 MCI subjects (mean age = 74.3 years, female = 61 %) who had baseline data of magnetic resonance imaging, clinical, and neuropsychological measurements were followed for two years. Multivariate logistic analyses were used to identify the predictors of MCI reversion after adjusting for age and sex. A stepwise backward logistic regression model was used to construct a predictive nomogram for MCI reversion. The nomogram was validated by internal bootstrapping and in an independent cohort.

RESULT

In the training cohort, the 2-year reversion rate was 19.95 %. Predictors associated with reversion to NC were higher education level (p = 0.004), absence of APOE4 allele (p = 0.001), larger brain volume (p < 0.005), better neuropsychological measurements performance (p < 0.001), higher glomerular filtration rate (p = 0.035), and lower mean arterial pressure (p = 0.060). The nomogram incorporating five predictors (education, hippocampus volume, the Alzheimer's Disease Assessment Scale-Cognitive score, the Rey Auditory Verbal Learning Test-immediate score, and mean arterial pressure) achieved good C-indexes of 0.892 (95 % confidence interval [CI], 0.859-0.926) and 0.806 (95 % CI, 0.709-0.902) for the training and validation cohort.

LIMITATION

Observational duration is relatively short; The predicting model warrant further validation in larger samples.

CONCLUSION

This prediction model could facilitate risk stratification and early management for the MCI population.

Examining the non-linear effects of education on Alzheimer's and non-Alzheimer's disease: Sex-stratified analysis of 17,671 older persons

BACKGROUND

Higher educational attainment is strongly associated with a reduced risk of neurocognitive disorders (NCDs). However, the literature is not yet clear on (1) the minimum years of compulsory education that would sufficiently mitigate the risk of NCDs, and (2) whether educational attainment has differential effects across sexes. To bridge these gaps, this study sought to model potential non-linear relationship between years of education and NCD risk, across men and women.

METHODS

The study recruited 17,671 participants from Alzheimer's Disease Centres across United States, aged≥50 years and had normal cognition at baseline. Participants were followed up almost annually, and underwent standardized assessments to diagnose various aetiologies of NCDs. Cox proportional hazard regression was conducted to examine the relationship between years of education and NCD risk, stratified by sexes. Years of education were modelled using restricted cubic spline.

RESULTS

Lesser years of education were associated with higher NCD risk in both sexes (specifically, when <12 years of education; HR 1.80-3.48), yet with key differences across sexes. In women, a linear relationship was observed whereby increasing years of education reduced NCD risk correspondingly; but in men, the relationship was non-linear whereby adding years of education beyond 12 years did not reduce NCD risk further. Men of lower educational attainment were at risk of both Alzheimer's Disease (AD; HR up to 3.45) and non-AD (HR up to 2.57), while women of lower educational attainment were only at risk of AD (HR up to 2.11).

CONCLUSIONS

Educational attainment alters NCD risk differently across sexes, emphasizing the relevance of sex-specific research to better understand the moderating role of sex on NCD risk. The findings also highlight the need to reconsider public policies related to equitable access to education, as well as traditional assumptions on the minimum years of compulsory education.

Analysis of Convergent Validity of Performance-Based Activities of Daily Living Assessed by PA-IADL Test in Relation to Traditional (Standard) Cognitive Assessment to Identify Older Adults with Mild Cognitive Impairment

Difficulty in performing instrumental activities of daily living (IADLs) is currently considered an important indicator of cognitive impairment in the elderly. A non-experimental case-control investigation was conducted to assess the convergent validity of the PA-IADL with traditional (standard) cognitive assessment tests in its ability to identify adults with mild cognitive impairment. The analysis of the data was carried out by means of various multivariate statistical tests, and the sequence in its execution led to the conclusion that 8 of the 12 Tasks that make up the PA-IADL allow for the identification of people with mild cognitive impairment (MCI) to the same extent as traditional cognitive assessment tests and regardless of age. Age was found to be a moderating variable in the performance of the eight tasks; however, the results allow us to hypothesize that people with MCI experience a significant decline when it happens but thereafter, the deterioration that occurs does so at the same rate as the deterioration experienced by healthy people. They also allow us to hypothesize that the difference in the cognitive skills required by the eight functional tasks, and therefore also in the cognitive skills required by the traditional (standard) tests of a person with MCI compared to a person of the same age without MCI (Healthy), is approximately 10 years. These hypotheses have remarkable relevance and should be tested via longitudinal research. In the meantime, the results highlight the importance of the IADL assessment for the diagnosis of MCI as a complement to the standard cognitive assessment.

Preventing Dementia-A Cross-Sectional Study of Outpatients in a Tertiary Internal Medicine Department

Dementia is a significant health problem worldwide, being the seventh leading cause of death (2,382,000 deaths worldwide in 2016). Recent data suggest there are several modifiable risk factors that, if addressed, can decrease dementia risk. Several national dementia screening programs exist; however, limited-income countries do not have the means to implement such measures. We performed a prospective cross-sectional study in an outpatient department to identify individuals at risk for dementia. Patients with no known cognitive dysfunction seeking a medical consult were screened for dementia risk by means of the cardiovascular risk factors, ageing, and dementia (CAIDE) and modified CAIDE tests. Additionally, we collected demographic and clinical data and assessed each participant for depression, mental state, and ability to perform daily activities. Of the 169 patients enrolled, 63.3% were identified as being in the intermediate-risk or high-risk group, scoring more than seven points on the mCAIDE test. Over 40% of the elderly individuals in the study were assessed as "somewhat depressed" or "depressed" on the geriatric depression scale. Almost 10% of the study population was diagnosed de novo with cognitive dysfunction. In conclusion, using a simple questionnaire such as the mCAIDE in a predefined high-risk population is easy and does not represent a major financial burden. At-risk individuals can subsequently benefit from personalized interventions that are more likely to be successful. Limited-resource countries can implement such screening tools in outpatient clinics.

Predictive ability of the clock drawing test to detect mild cognitive impairment and dementia over time: Results from the HELIAD study

Objective: We investigated the diagnostic accuracy of the Clock Drawing Test (CDT) in discriminating Mild Cognitive Impairment (MCI) and dementia from normal cognition. Additionally, its clinical utility in predicting the transition from normal cognition to MCI and dementia over the course of several years was explored. Method: In total, 1037 older adults (633 women) who completed the CDT in a baseline assessment were drawn from the population-based HELIAD cohort. Among these, 848 participants were identified as cognitively normal, 142 as having MCI and 47 with dementia during the baseline assessment. Of these individuals, 565 attended the follow-up assessment (mean interval: 3.21 years). ROC curve and binary logistic regression analyses were performed. Results: The CDT exhibited good diagnostic accuracy for the discrimination between dementia and normal cognition (AUC = .879, SN = .813, SP = .778, LR+ = 3.66, LR- = .240, < .001, d = 1.655) and acceptable diagnostic accuracy for the discrimination between dementia and MCI (AUC=.761, SN= .750, SP= .689, LR+ = 2.41, LR- = .362, p < .001, d = 1.003). We found limited diagnostic accuracy, however, for the discrimination between MCI and normal cognition (AUC = .686, SN = .764, SP = .502, LR+ = 1.53, LR- = .470, p < .001, d = .685). Moreover, the CDT significantly predicted the transition from normal cognition to dementia [Exp(B)= 1.257, p = .022], as well as the transition from MCI to normal cognition [Exp(B) = 1.334, p = .023] during the longitudinal investigation. Conclusions: The CDT is a neuropsychological test with acceptable diagnostic accuracy for the discrimination of dementia from MCI and normal cognition. Furthermore, it has an important predictive value for the transition from normal cognition to dementia and from MCI to normal cognition.

Features of Interferon Status and Methods of Its Correction in the Treatment of Patients with Atypical Chronic Active Herpesvirus Infections

It is known that the imbalance of the IFN system is the cornerstone of the immunopathogenesis of atypical chronic active herpesvirus infections and is often associated not only with congenital, genetically determined defects, but also with acquired system dysregulation at different levels: receptor, molecular, at the level of a nuclear transducer of signal transmission. Based on the studied features of immunopathogenesis and the revealed disturbances in the antiviral immune defense system and the IFN system in patients with atypical chronic herpes viral infections, an integration program for correcting IFN status was developed, its clinical and immunological effectiveness was evaluated. Improved effectiveness of complex rehabilitation of immunocompromised patients with atypical chronic active herpes viral infections was demonstrated.

Exploring the Impact of Age of Onset of Mild Cognitive Impairment on the Profile of Cognitive and Psychiatric Symptoms

The present study aims to explore the differences in the manifestation of cognitive decline and psychiatric symptoms across the different ages of MCI onset: early onset (EOMCI: <65 years old), middle onset (MOMCI: 65-75 years old), and late onset (LOMCI: >75 years old). It was hypothesized that individuals with EOMCI will preserve their cognitive functions to a greater extent as compared to individuals with LOMCI, even after adjusting the cognitive performance for age and education through the use of published Greek norms. The level of cognitive decline concerning MOMCI was evaluated for extracting more precise conclusions regarding the impact of the age of onset on the patterns of MCI symptomatology. The analyses of data were conducted in a Greek population of individuals with MCI, who were consecutive visitors of the Outpatient Memory Clinic of Nestor Alzheimer's Centre in Athens, Greece. The sample consisted of 297 participants who fulfilled the following inclusion criteria: MCI diagnosis based on Petersen's criteria, Greek mother language, and absence of a psychiatric history or chronic and incurable organic disease. The overall results support the presence of a cognitive advantage of the EOMCI group compared to the LOMCI group. In the MOMCI group, cognitive performance displayed a tendency to remain intermediate compared to the other two groups. Nonetheless, significant differences were observed when this group was compared with the LOMCI group. The current findings indicate that the age of onset should be taken under consideration in the neuropsychological assessment of individuals with MCI. The specific parameters could have implications in terms of prognosis as well as the design and implementation of tailored interventions.

Analysis of Why Alzheimer's Dementia Never Spontaneously Reverses, Suggests the Basis for Curative Treatment

A paradox regarding Alzheimer's dementia (AD) and mild cognitive impairment (MCI) is thats spontaneous cure of AD has never been reported, whereas spontaneous cure for MCI occurs fequently. This article analyzes what accounts for this difference. It holds that it is not merely because, for any condition, a stage is reached beyond which it cannot be reversed, since even widely metastatic cancer would be curable were there effective chemotherapy and rheumatoid arthritis became controllable when immune-suppressant treatment was introduced; thus, so could AD be reversible via effective therapy. The analysis presented leads to an explanation of the paradox that is in four categories: (1) levels of transforming growth factor-β are significantly reduced after the transition from MCI to AD; (2) levels of Wnt/β-catenin are significantly reduced after the transition; (3) there is altered epidermal-mesenchymal transition (EMT) in neurons after the transition; (4) there may be risk factors that are either newly operative or pre-existing but worsened at the time of transition, that are particular to individual patients. It is suggested that addressing and ameliorating all of those four categories might cure AD. Medications to address and ameliorate each of the four categories are described.

Acquisition and consolidation of verbal learning and episodic memory as predictors of the conversion from mild cognitive impairment to probable Alzheimer's disease

Verbal episodic memory tests assess memory performance using total learning scores. The analysis of inter-trial indices such as gained (GA) and lost (LA) access can provide additional information on the acquisition and consolidation processes. The main objetive was to determine whether the GA and LA indices, derived from a word-list verbal episodic memory test are useful for predicting cognitive impairment in aging. 60 older people aged was divided into 3 groups: cognitively healthy, stable Mild Cognitive Impairment (MCI) and MCI converting to probable Alzheimer's disease (MCI-conv). The results showed that GA and LA measures are independent from the traditional measures -total score of correct answers-. Logistic regression showed that these values are predictive of the conversion over time and could be a cognitive marker of conversion from MCI to AD. This suggests that the GA index, which shows acquisition processes in word-list tests, may be a marker of cognitive impairment.

Mild Cognitive Impairment, Reversion Rates, and Associated Factors: Comparison of Two Diagnostic Approaches

BACKGROUND

As mild cognitive impairment (MCI) is typically used to identify prodromal stages of dementia, it is essential to identify MCI criteria with high diagnostic stability and prediction of dementia. Moreover, further investigation into pinpointing key factors for reversion is required to foresee future prognosis of MCI patients accurately.

OBJECTIVE

To explore disparities in diagnostic stability by examining reversion rates produced by two operationalizations of the MCI definition: the widely applied Petersen criteria and a version of the Neuropsychological (NP) criteria and to identify cognitive, lifestyle, and health related factors for reversion.

METHODS

MCI was retrospectively classified in a sample from the Swedish community-based study Good Aging in Skåne with the Petersen criteria (n = 744, median follow-up = 7.0 years) and the NP criteria (n = 375, median follow-up, 6.7 years), respectively. Poisson regression models estimated the effect of various factors on the likelihood of incident reversion.

RESULTS

Reversion rates were 323/744 (43.4%, 95% confidence intervals (CI): 39.8; 47.0) and 181/375 (48.3% 95% CI: 43.2; 53.5) for the Petersen criteria and NP criteria, respectively. Participants with impairment in a single cognitive domain, regular alcohol consumption, living with someone, older age, and lower body mass index had a higher likelihood of reverting to normal.

CONCLUSION

Reversion rates were similar for Petersen and NP criteria indicating that one definition is not superior to the other regarding diagnostic stability. Additionally, the results highlight important aspects such as multiple domain MCI, cohabitation, and the role of alcohol on predicting the trajectory of those diagnosed with MCI.

The association between leisure activity patterns and the prevalence of mild cognitive impairment in community-dwelling older adults

Objectives

The study aimed to identify leisure activity patterns among older adults and explore the differences in the prevalence of mild cognitive impairment (MCI) of these patterns.

Methods

A total of 352 older adults aged ≥ 65 years in Shijiazhuang were enrolled in this study from June to September 2021. Their leisure activities and cognition were evaluated. Latent class analysis and logistic regression models were used for analysis. The manuscript was organized according to the STROBE guidelines.

Results

We identified three latent classes of leisure activities: multidomain activities (MDA) class (55%), self-improvement activities (SIA) class (21%), and family-centered activities (FCA) class (24%). Three latent classes significantly differed in general characteristics (gender, education, and body mass index) and the prevalence of MCI. The prevalence of MCI was 3.694 times higher in older adults in the FCA class than in older adults in the MDA class (OR = 3.694, P < 0.001) and 2.573 times higher in older adults in the SIA class (OR = 2.573, P = 0.036).

Conclusion

Patterns of low participation in intellectual activities were associated with MCI. Identifying the heterogeneity in leisure activity engagement in later life was critical for tailoring interventions and designing programs that can improve the cognitive function of older adults.

[Predictors of the efficacy of non-drug treatments for non-dementia vascular cognitive impairment]

OBJECTIVE

To study the predictors of the efficacy of non-drug multimodal therapy in the treatment of mild vascular cognitive impairment.

MATERIAL AND METHODS

Thirty patients with mild vascular cognitive impairment, under the supervision of their physician, received a 1-month non-drug treatment program including cognitive training, detailed recommendations for physical activity, and dietary planning.

RESULTS

After the end of the course of treatment, improvements in the MoCa test were achieved by 22 patients (73%), which made up Group 1. In the remaining 8 patients, the treatment had no effect (Group 2). In Group 1, the dynamics of the MoCa test averaged 1.7±0.9, in the Group 2 it was (-0.4)±0.5. Patients of Group 1 had a significantly lower level of education (10.9±2.3) compared with Group 2 (14.9±2.0), a higher initial MoCa score, and a less pronounced white matter lesion on the Fazekas scale. After the regression analysis, the level of education (B -0.999, p<0.05) and white matter damage (B -2.761, p<0.01) were significant predictors.

CONCLUSION

When using non-drug multimodal therapy in the treatment of mild vascular cognitive impairment, lower levels of education and a lower degree of white matter vascular damage are reliable predictors of treatment efficacy.

Association of leisure activity changes and reversion from mild cognitive impairment to normal cognitive function among older adults: A prospective cohort study

Background

Older adults with mild cognitive impairment (MCI) have the possibility of reverting to normal cognitive function. Leisure activity engagement (LAE) plays a critical role in the progress of the cognitive function. A better understanding of the dynamic relationship between LAE and MCI reversion would inform the implementation of preclinical dementia interventions. This study aimed to investigate the association between change patterns of LAE and MCI reversion among older adults using the Chinese Longitudinal Healthy Longevity Survey (CLHLS) database.

Study design

Longitudinal population-based study.

Methods

Older adults with MCI at the baseline were enrolled in this study. Information about cognitive function, overall, cognitively stimulating, physically active/demanding, and socially engaged LAE was collected at baseline and follow-up. Adjusted hazard ratios (HRs) for reversion and 95% confidence intervals (CIs) were calculated by Cox hazard models with time as the underlying time metric. We also assessed potential effect modifications by creating a cross-product of the stratifying variable with LAE change patterns in the fully adjusted model.

Results

The restricted cubic spline showed that the association between LAE change scores and MCI reversion rate was statistically significant and nonlinear (p<0.01). Taking participants in the low-low group as a reference, participants in the low-medium, low-high, medium-medium, medium-high, high-medium, and high-high groups had increased possibilities of MCI reversion with HRs (95% CI) of 2.19 (1.57-3.06), 2.97 (2.13-4.13), 0.87 (0.64-1.19), 2.28 (1.71-3.03), 2.78 (2.10-3.69), 1.93 (1.43-2.59), and 2.74 (2.09-3.60), respectively. Further stratified models showed that the impact of LAE change patterns on MCI reversion varied in different ages (nonagenarian, octogenarian, and younger elderly) and gender.

Conclusions

Participants who maintained the highest LAE had the greatest possibility of MCI reversion. Meanwhile, a higher level of LAE maintenance was associated with the increased possibility of MCI reversion. These results provide a practical message to older adults about how dynamic changes in LAE are associated with improved cognitive function.

Progression to Dementia or Reversion to Normal Cognition in Mild Cognitive Impairment as a Function of Late-Onset Neuropsychiatric Symptoms

BACKGROUND AND OBJECTIVES

Mild cognitive impairment (MCI) is an at-risk state for dementia; however, not all individuals with MCI transition to dementia, and some revert to normal cognition (NC). Here, we investigate whether mild behavioral impairment (MBI), the late-life onset of persistent neuropsychiatric symptoms (NPS), improves the prognostic specificity of MCI.

METHODS

Participants with MCI from the National Alzheimer's Coordinating Center Uniform Data Set were included. NPS were operationalized with the Neuropsychiatric Inventory Questionnaire to identify participants without NPS and those with MBI (persistent, late-onset NPS). Individuals with late-onset NPS not meeting the MBI persistence criterion (NPS_NOT_MBI) were retained for secondary analyses. Progression to dementia, stable MCI, and reversion to NC after 3 years of follow-up were defined per National Institute on Aging-Alzheimer's Association and Petersen criteria.

RESULTS

The primary sample consisted of 739 participants (NPS- n = 409 and MBI+ n = 330; 75.16 ± 8.6 years old, 40.5% female). After 3 years, 238 participants (33.6%) progressed to dementia, and 90 (12.2%) reverted to NC. Compared to participants without NPS, participants with MBI were significantly more likely to progress to dementia (adjusted odds ratio [AOR] 2.13, 95% CI 1.52-2.99), with an annual progression rate of 14.7% (vs 8.3% for participants with MCI without NPS). Compared to participants without NPS, participants with MBI were less likely to revert to NC (AOR 0.48, 95% CI 0.28-0.83, 2.5% vs 5.3% annual reversion rate). The NPS_NOT_MBI group (n = 331, 76.5 ± 8.6 years old, 45.9% female) were more likely to progress to dementia (AOR 2.18, 95% CI 1.56-3.03, 14.3% annual progression rate) but not less likely to revert to NC than those without NPS. Accordingly, both NPS_NOT_MBI and MBI+ participants had lower Mini-Mental State Examination scores than NPS- participants after 3 years.

DISCUSSION

Late-onset NPS improve the specificity of MCI as an at-risk state for progression to dementia. However, only persistent late-onset NPS are associated with a lower likelihood of reversion to NC, with transient NPS (i.e., NPS_NOT_MBI) not differing from the NPS- group. Clinical prognostication can be improved by incorporating late-onset NPS, especially those that persist (i.e., MBI), into risk assessments. Clinical trials may benefit from enrichment with these higher-risk participants with MCI.

Modifiable Factors Associated with Reversion from Mild Cognitive Impairment to Cognitively Normal Status: A Prospective Cohort Study

Background: Previous studies found that about 24% of the mild cognitive impairment (MCI) patients reverse to cognitive normal (CN) status. However, it is unclear which modifiable factors are associated with this reversion. Objective: To identify potential modifiable factors associated with the reversion of MCI to CN status. Methods: We conducted a prospective community-based cohort study based on 2002–2018 Chinese Longitudinal Health Longevity Survey (CLHLS). Multivariable Cox regression with least absolute shrinkage and selection operator (LASSO) penalty for variable selection was adopted to investigate the associations between reversion to CN and potential modifiable dietary/lifestyle, cardiometabolic, and psychological factors. Results: Our analysis included 7,422 MCI participants [average age: 90.0 (SD 9.5) years]. Among these participants, 1,604 (21.6%) reversed from MCI to CN with a mean (SD) follow-up of 2.9 (1.8) years. Several dietary/lifestyle factors, including daily consumption of fresh fruits (Hazard Ratio [HR]: 1.28, 95% CI: 1.15 to 1.42), engagement in reading (HR: 1.24, 95% CI: 1.00 to 1.54), housework (HR: 1.21, 95% CI: 1.08 to 1.35), and mah-jongg or other card games (HR: 1.23, 95% CI: 1.08 to 1.39), were positively associated with possibility of reversion. Cigarette smoking (HR: 0.92, 95% CI: 0.84 to 1.00) and duration of alcohol drinking (HR: 0.97, 95% CI: 0.94 to 0.99) were negatively associated with possibility of reversion. None of the modifiable cardiometabolic and psychological factors was found to be significantly associated with reversion to CN. Conclusion: This study identified several dietary/lifestyle factors associated with MCI reversion that may transfer into large-scale dementia prevention practices.

Cognitive Reserve and Mild Cognitive Impairment: Predictors and Rates of Reversion to Intact Cognition vs Progression to Dementia

Background and Objectives

Little is known about the effect of education or other indicators of cognitive reserve on the rate of reversion from mild cognitive impairment (MCI) to normal cognition (NC) or the relative rate (RR) of reversion from MCI to NC vs progression from MCI to dementia. Our objectives were to (1) estimate transition rates from MCI to NC and dementia and (2) determine the effect of age, APOE, and indicators of cognitive reserve on the RR of reversion vs progression using multistate Markov modeling.

Methods

We estimated instantaneous transition rates between NC, MCI, and dementia after accounting for transition to death across up to 12 assessments in the Nun Study, a cohort study of religious sisters aged 75+ years. We estimated RRs of reversion vs progression for age, APOE, and potential cognitive reserve indicators: education, academic performance (high school grades), and written language skills (idea density, grammatical complexity).

Results

Of the 619 participants, 472 were assessed with MCI during the study period. Of these 472, 143 (30.3%) experienced at least one reverse transition to NC, and 120 of the 143 (83.9%) never developed dementia (mean follow-up = 8.6 years). In models adjusted for age group and APOE, higher levels of education more than doubled the RR ratio of reversion vs progression. Novel cognitive reserve indicators were significantly associated with a higher adjusted RR of reversion vs progression (higher vs lower levels for English grades: RR ratio = 1.83; idea density: RR ratio = 3.93; and grammatical complexity: RR ratio = 5.78).

Discussion

Knowledge of frequent reversion from MCI to NC may alleviate concerns of inevitable cognitive decline in those with MCI. Identification of characteristics predicting the rate of reversion from MCI to NC vs progression from MCI to dementia may guide population-level interventions targeting these characteristics to prevent or postpone MCI and dementia. Research on cognitive trajectories would benefit from incorporating predictors of reverse transitions and competing events, such as death, into statistical modeling. These results may inform the design and interpretation of MCI clinical trials, given that a substantial proportion of participants may experience improvement without intervention.

Intrinsic Brain Activity Alterations in Patients With Mild Cognitive Impairment-to-Normal Reversion: A Resting-State Functional Magnetic Resonance Imaging Study From Voxel to Whole-Brain Level

Mild cognitive impairment (MCI) reversion refers to patients with MCI who revert from MCI to a normal cognitive state. Exploring the underlying neuromechanism of MCI reverters may contribute to providing new insights into the pathogenesis of Alzheimer's disease and developing therapeutic interventions. Information on patients with MCI and healthy controls (HCs) was collected from the Alzheimer's Disease Neuroimaging Initiative database. We redefined MCI reverters as patients with MCI whose logical memory scores changed from MCI to normal levels using the logical memory criteria. We explored intrinsic brain activity alterations in MCI reverters from voxel, regional, and whole-brain levels by comparing resting-state functional magnetic resonance imaging metrics of the amplitude of low-frequency of fluctuation (ALFF), the fractional amplitude of low-frequency fluctuation (fALFF), percent amplitude of fluctuation (PerAF), regional homogeneity (ReHo), and degree centrality (DC) between MCI reverters and HCs. Finally, partial correlation analyses were conducted between cognitive scale scores and resting-state functional magnetic resonance imaging metrics of brain regions, revealing significant group differences. Thirty-two patients with MCI from the Alzheimer's Disease Neuroimaging Initiative database were identified as reverters. Thirty-seven age-, sex-, and education-matched healthy individuals were also enrolled. At the voxel level, compared with the HCs, MCI reverters had increased ALFF, fALFF, and PerAF in the frontal gyrus (including the bilateral orbital inferior frontal gyrus and left middle frontal gyrus), increased PerAF in the left fusiform gyrus, and decreased ALFF and fALFF in the right inferior cerebellum. Regarding regional and whole-brain levels, MCI reverters showed increased ReHo in the left fusiform gyrus and right median cingulate and paracingulate gyri; increased DC in the left inferior temporal gyrus and left medial superior frontal; decreased DC in the right inferior cerebellum and bilateral insular gyrus relative to HCs. Furthermore, significant correlations were found between cognitive performance and neuroimaging changes. These findings suggest that MCI reverters show significant intrinsic brain activity changes compared with HCs, potentially related to the cognitive reversion of patients with MCI. These results enhance our understanding of the underlying neuromechanism of MCI reverters and may contribute to further exploration of Alzheimer's disease.

Transition from mild cognitive impairment to normal cognition: Determining the predictors of reversion with multi-state Markov models

INTRODUCTION

The theoretical framework of the Alzheimer's disease continuum considers transition between stages in a unidirectional manner. Here we examine the rate of reversion from mild cognitive impairment (MCI) to normal cognition (NC) and explore a set of potential variables associated with this phenomenon.

METHODS

A total of 985 Spanish community-dwelling individuals aged 70 years and over at baseline were monitored for 5 years. During this time, 173 MCI and 36 dementia cases were identified. Multi-state Markov models were performed to characterize transitions between states through the dementia continuum.

RESULTS

The rate of reversion from MCI to NC was 11%. There were significant non-modifiable (age, socioeconomic status, or apolipoprotein E) and modifiable factors (cognitive training or absence of affective symptoms) associated with reversion.

DISCUSSION

Overall, our results highlight that the likelihood of progression from MCI to dementia is very similar to that of reversion from MCI to NC.

Characteristics of Resting State EEG Power in 80+-Year-Olds of Different Cognitive Status

Compared with healthy older adults, patients with Alzheimer's disease show decreased alpha and beta power as well as increased delta and theta power during resting state electroencephalography (rsEEG). Findings for mild cognitive impairment (MCI), a stage of increased risk of conversion to dementia, are less conclusive. Cognitive status of 213 non-demented high-agers (mean age, 82.5 years) was classified according to a neuropsychological screening and a cognitive test battery. RsEEG was measured with eyes closed and open, and absolute power in delta, theta, alpha, and beta bands were calculated for nine regions. Results indicate no rsEEG power differences between healthy individuals and those with MCI. There were also no differences present between groups in EEG reactivity, the change in power from eyes closed to eyes open, or the topographical pattern of each frequency band. Overall, EEG reactivity was preserved in 80+-year-olds without dementia, and topographical patterns were described for each frequency band. The application of rsEEG power as a marker for the early detection of dementia might be less conclusive for high-agers.

Prevalence of Mild Cognitive Impairment in the Lothian Birth Cohort 1936

BACKGROUND

The Lothian Birth Cohort 1936 (LBC1936) is a highly phenotyped longitudinal study of cognitive and brain ageing. Given its substantial clinical importance, we derived an indicator of mild cognitive impairment (MCI) and amnestic and nonamnestic subtypes at 3 time points.

METHODS

MCI status was derived at 3 waves of the LBC1936 at ages 76 (n=567), 79 (n=441), and 82 years (n=341). A general MCI category was derived as well as amnestic MCI (aMCI) and nonamnestic MCI (naMCI). A comparison was made between MCI derivations using normative data from the LBC1936 cohort versus the general UK population.

RESULTS

MCI rates showed a proportional increase at each wave between 76 and 82 years from 15% to 18%. Rates of MCI subtypes also showed a proportional increase over time: aMCI 4% to 6%; naMCI 12% to 16%. Higher rates of MCI were found when using the LBC1936 normative data to derive MCI classification rather than UK-wide norms.

CONCLUSIONS

We found that MCI and aMCI rates in the LBC1936 were consistent with previous research. However, naMCI rates were higher than expected. Future LBC1936 research should assess the predictive factors associated with MCI prevalence to validate previous findings and identify novel risk factors.

Towards a Redefinition of Cognitive Frailty

Background:

The progressive aging of the population will dramatically increase the burden of dementia related to Alzheimer’s disease (AD) and other neurodegenerative disorders in the future. Because of the absence of drugs that can modify the neuropathological substrate of AD, research is focusing on the application of preemptive and disease-modifying strategies in the pre-symptomatic period of the disease. In this perspective, the identification of people with cognitive frailty (CF), i.e., those individuals with higher risk of developing dementia, on solid pathophysiological bases and with clear operational clinical criteria is of paramount importance.

Objective/Methods:

This hypothesis paper reviews the current definitions of CF, presents and discusses some of their limitations, and proposes a framework for updating and improving the conceptual and operational definition of the CF construct.

Results:

The potential for reversibility of CF should be supported by the assessment of amyloid, tau, and neuronal damage biomarkers, especially in younger patients. Physical and cognitive components of frailty should be considered as separate entities, instead of part of a single macro-phenotype. CF should not be limited to the geriatric population, because trajectories of amyloid accumulation are supposed to start earlier than 65 years in AD. Operational criteria are needed to standardize assessment of CF.

Conclusion:

Based on the limitations of current CF definitions, we propose a revised one according to a multidimensional subtyping. This new definition might help stratifying CF patients for future trials to explore new lifestyle interventions or disease-modifying pharmacological strategies for AD and dementia.

Diabetes and Prediabetes Inhibit Reversion from Mild Cognitive Impairment to Normal Cognition

OBJECTIVES

Diabetes and prediabetes contribute to an increased risk of cognitive decline and dementia. Currently, it remains unclear whether elevated blood HbA1c levels, including prediabetes levels, affect reversion from mild cognitive impairment (MCI) to normal cognition. This study, therefore, aimed to examine the prospective associations of diabetes and prediabetes with reversion from MCI to normal cognition among community-dwelling older adults.

DESIGN

Longitudinal cohort study with a 4-year follow-up.

SETTING AND PARTICIPANTS

Community-dwelling older adults with MCI, aged ≥65 years at baseline (n = 787).

METHODS

Participants' medical history of diabetes and blood HbA1c levels at baseline were assessed, and they were classified as control, prediabetes, and diabetes. Objective cognitive screening was performed using a multicomponent neurocognitive test at baseline and follow-up. Reversion from MCI to normal cognition over 4 years was determined. In the longitudinal analysis, we performed multiple imputations to adjust for a selection bias and loss of information.

RESULTS

The reversion rates of MCI in the control, prediabetes, and diabetes groups were 63.4%, 55.6%, and 42.9%, respectively, in the completed follow-up dataset, and 54.6%, 47.2%, and 34.1%, respectively, in the imputed dataset. Multivariate logistic regression showed that diabetes decreases the probability of MCI reversion both before and after multiple imputations [odds ratio (OR) 0.37; 95% confidence interval (CI) 0.18-0.74 for before imputation, OR 0.37; 95% CI 0.19-0.72 for after imputation]. Furthermore, prediabetes also showed significantly decreased probabilities of MCI reversion both before and after multiple imputations (OR 0.57; 95% CI 0.34-0.94 for before imputation, OR 0.60; 95% CI 0.37-0.97 for after imputation).

CONCLUSIONS AND IMPLICATIONS

Diabetes and prediabetes could inhibit MCI reversion. Adequate glycemic control may be effective in enhancing the reversion from MCI to normal cognition in a community setting.

Biological Features of Reversion from Mild Cognitive Impairment to Normal Cognition: A Study of Cerebrospinal Fluid Markers and Brain Volume

BACKGROUND

Mild cognitive impairment (MCI) is a transitional condition between normal cognition and dementia. Although a significant proportion of the population with MCI experience reversion to normal cognition, it is still poorly understood.

OBJECTIVE

This study was designed to extend the present evidence regarding the difference between stable and reverting MCI by including whole brain atrophy measures as possible parameters involved.

METHODS

405 patients diagnosed with MCI at baseline were selected. After one-year follow-up period, 337 patients (83.2%) were categorized as stable MCI and 68 patients (16.8%) reverted to cognitively normal status (reversion group). Several baseline biomarkers including cerebrospinal fluid (CSF) biomarkers of AD, including Aβ42, t-tau, and p-tau and MRI-based atrophy measurements were compared.

RESULTS

Participants with stable MCI demonstrated greater brain atrophy as well as lower Aβ and higher tau proteins in the CSF. The atrophy rate was found to be associated with CSF biomarkers merely in the stable group, after adjustment for confounding variables.

CONCLUSION

These findings provide novel evidence regarding the biological perspective of the reversion phenomenon in individuals with MCI.

The Power of EEG to Predict Conversion from Mild Cognitive Impairment and Subjective Cognitive Decline to Dementia

INTRODUCTION

The aim of this study was to examine if quantitative electroencephalography (qEEG) using the statistical pattern recognition (SPR) method could predict conversion to dementia in patients with subjective cognitive decline (SCD) and mild cognitive impairment (MCI).

METHODS

From 5 Nordic memory clinics, we included 47 SCD patients, 99 MCI patients, and 67 healthy controls. EEGs analyzed with the SPR method together with clinical data recorded at baseline were evaluated. The patients were followed up for a mean of 62.5 (SD 17.6) months and reexamined.

RESULTS

Of 200 participants with valid clinical information, 70 had converted to dementia, and 52 had developed Alzheimer's disease. Receiver-operating characteristic analysis of the EEG results as defined by a dementia index (DI) ranging from 0 to 100 revealed that the area under the curve was 0.78 (95% CI 0.70-0.85), corresponding to a sensitivity of 71%, specificity of 69%, and accuracy of 69%. A logistic regression analysis showed that by adding results of a cognitive test at baseline to the EEG DI, accuracy could improve.

CONCLUSION

We conclude that applying qEEG using the automated SPR method can be helpful in identifying patients with SCD and MCI that have a high risk of converting to dementia over a 5-year period. As the discriminant power of the method is of moderate degree, it should be used in addition to routine diagnostic methods.

Predictors of Mild Cognitive Impairment Stability, Progression, or Reversion in the Lothian Birth Cohort 1936

BACKGROUND

Mild cognitive impairment (MCI) describes a borderland between healthy cognition and dementia. Progression to and reversion from MCI is relatively common but more research is required to understand the factors affecting this fluidity and improve clinical care interventions.

OBJECTIVE

We explore these transitions in MCI status and their predictive factors over a six-year period in a highly-phenotyped longitudinal study, the Lothian Birth Cohort 1936.

METHODS

MCI status was derived in the LBC1936 at ages 76 (n = 567) and 82 years (n = 341) using NIA-AA diagnostic guidelines. Progressions and reversions between healthy cognition and MCI over the follow-up period were assessed. Multinomial logistic regression assessed the effect of various predictors on the likelihood of progressing, reverting, or maintaining cognitive status.

RESULTS

Of the 292 participants who completed both time points, 41 (14%) participants had MCI at T1 and 56 (19%) at T2. Over the follow-up period, 74%remained cognitively healthy, 12%transitioned to MCI, 7%reverted to healthy cognition, and 7%maintained their baseline MCI status. Findings indicated that membership of these transition groups was affected by age, cardiovascular disease, and number of depressive symptoms.

CONCLUSION

Findings that higher baseline depressive symptoms increase the likelihood of reverting from MCI to healthy cognition indicate that there may be an important role for the treatment of depression for those with MCI. However, further research is required to identify prevention strategies for those at high risk of MCI and inform effective interventions that increase the likelihood of reversion to, and maintenance of healthy cognition.

Diagnostic Stability of Mild Cognitive Impairment, and Predictors of Reversion to Normal Cognitive Functioning

OBJECTIVE

Studies that investigate predictive factors for spontaneous recovery (reversion) from mild cognitive impairment (MCI) are only beginning to emerge, and the long-term course of MCI is not properly understood. We aimed to investigate stability of the MCI diagnosis, predictors for reversion, as well as the trajectory of MCI over the course of 12 years.

MATERIALS AND METHODS

Data were drawn from the Swedish population study: Good Aging in Skåne with MCI defined according to the expanded Mayo Clinic criteria. A total of 331 participants, aged 60-95 years with MCI, were used to investigate 6-year MCI stability and reversion, and 410 participants were used to inspect 12-year MCI trajectory. Predictors for reversion included demographical factors, psychological status, and factors tied to the cognitive testing session and the operationalization of the MCI criteria.

RESULTS

Over half (58%, 95% CI 52.7-63.3) of the participants reverted back to normal cognitive functioning at 6-year follow-up. Of those with stable MCI, 56.5% (95% CI 48.2-64.8) changed subtype. A total of 23.9% (95% CI 13.7-34.1) of the 6-year follow-up reverters re-transitioned back to MCI at 12-year follow-up. ORs for reversion were significantly higher in participants with lower age (60-year-olds: OR 2.19, 95% CI 1.08-4.43, 70-year-olds: OR 3.11, 95% CI 1.27-7.62), better global cognitive functioning (OR 1.15, 95% CI 1.03-1.29), good concentration (OR 2.53, 95% CI 1.06-6.05), and single-domain subtype (OR 2.68, 95% CI 1.51-4.75).

CONCLUSION

Our findings provide further support that MCI reversion to normal cognitive functioning as well as re-transitioning to MCI is fairly common, suggesting that the MCI trajectory does not necessarily lead straight to dementia. Additionally, assessment of factors associated with reversion can aid clinicians to make accurate MCI progression prognosis.

Machine Learning Analysis of Digital Clock Drawing Test Performance for Differential Classification of Mild Cognitive Impairment Subtypes Versus Alzheimer's Disease

OBJECTIVE

To determine how well machine learning algorithms can classify mild cognitive impairment (MCI) subtypes and Alzheimer's disease (AD) using features obtained from the digital Clock Drawing Test (dCDT).

METHODS

dCDT protocols were administered to 163 patients diagnosed with AD(n = 59), amnestic MCI (aMCI; n = 26), combined mixed/dysexecutive MCI (mixed/dys MCI; n = 43), and patients without MCI (non-MCI; n = 35) using standard clock drawing command and copy procedures, that is, draw the face of the clock, put in all of the numbers, and set the hands for "10 after 11." A digital pen and custom software recorded patient's drawings. Three hundred and fifty features were evaluated for maximum information/minimum redundancy. The best subset of features was used to train classification models to determine diagnostic accuracy.

RESULTS

Neural network employing information theoretic feature selection approaches achieved the best 2-group classification results with 10-fold cross validation accuracies at or above 83%, that is, AD versus non-MCI = 91.42%; AD versus aMCI = 91.49%; AD versus mixed/dys MCI = 84.05%; aMCI versus mixed/dys MCI = 84.11%; aMCI versus non-MCI = 83.44%; and mixed/dys MCI versus non-MCI = 85.42%. A follow-up two-group non-MCI versus all MCI patients analysis yielded comparable results (83.69%). Two-group classification analyses were achieved with 25-125 dCDT features depending on group classification. Three- and four-group analyses yielded lower but still promising levels of classification accuracy.

CONCLUSION

Early identification of emergent neurodegenerative illness is criterial for better disease management. Applying machine learning to standard neuropsychological tests promises to be an effective first line screening method for classification of non-MCI and MCI subtypes.

Neuropsychological assessment of mild cognitive impairment in Latinx adults: A scoping review

Objective: Latinx populations are rapidly growing and aging in the United States. There is a critical need to accurately and efficiently detect those at risk for dementia, particularly those with mild cognitive impairment (MCI). MCI diagnosis often relies on neuropsychological assessment, although cultural, demographic, and linguistic characteristics may impact test scores. This study provides a scoping review of neuropsychological studies on MCI in Hispanic/Latinx populations to evaluate how studies report and account for these factors in diagnosis of MCI. Method: Studies were identified using Web of Science, PubMed, and Scopus, using search terms (Hispanic* OR Latin* OR "Mexican American*" OR "Puerto Ric*" OR Caribbean) and ("Mild Cognitive Impairment" OR MCI). Studies using neuropsychological tests in diagnosis of MCI for Latinx individuals in the United States were identified. Sample characterization (e.g., country of origin, literacy, language preference and proficiency), neuropsychological testing methods (e.g., test selection and translation, normative data source), and method of MCI diagnosis were reviewed. Results: Forty-four articles met inclusion criteria. There was considerable variability in reporting of demographic, cultural and linguistic factors across studies of MCI in Latinx individuals. For example, only 5% of studies reported nativity status, 52% reported information on language preference and use, and 34% reported the method and/or source of test translation and adaptation. Conclusions: Future studies of diagnosis of MCI in Latinx individuals should report cultural details and use of appropriate neuropsychological assessment tools and normative data. This is important to accurately estimate the prevalence of MCI in Latinx individuals. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Modifiable Risk Factor Possession Patterns of Dementia in Elderly with MCI: A 4-Year Repeated Measures Study

This study clarified the patterns of possessing modifiable risk factors of dementia that can be corrected by the elderly who were primarily determined to have mild cognitive impairment (MCI), and then determined the relationship between retention patterns and outcomes from MCI through a 4-year follow-up study. The participants were 789 community-dwelling elders who were ≥65 years old with MCI at baseline. After 4 years, participants were classified into reverters and nonreverters, according to their cognitive function. Repeated measures analysis was performed after imputing missing values due to dropout. Nine modifiable risk factors at baseline were classified by latent class analysis. Subsequently, we performed binomial logistic regression analysis. The reversion rate of 789 participants was 30.9%. The possession patterns of modifiable risk factors among the elderly with MCI were classified into five patterns: low risk, psychosocial, health behavior, educational, and smoking factors. According to logistic regression analysis, the low risk factors class was more likely to recover from MCI to normal cognitive than the other classes (p < 0.05). These results may provide useful information for designing interventions to prevent cognitive decline and dementia in individuals with MCI.

Predictors for Favorable Cognitive Outcome Post-Stroke: A-Seven-Year Follow-Up Study

BACKGROUND AND PURPOSE

Knowledge of the burden and development of post-stroke cognitive impairments (CIs) in the long-term after the first event is limited. We aimed to assess the prevalence of mild CI (MCI) and dementia 7 years after first-ever stroke or transient ischemic attack (TIA), to subclassify the impairments, and to identify predictors for a favorable cognitive outcome.

MATERIALS AND METHODS

During 2007 and 2008, 208 patients with first-ever stroke or TIA without preexisting CI were included. After 1 and 7 years, survivors were invited to a follow-up. Transitions of cognitive status from 1 to 7 years were recorded based on the 3 categories dementia, MCI, or none. Etiologic subclassification was based on clinical cognitive profile, magnetic resonance imaging (MRI) findings, and biomarkers at both time points. Favorable outcome was defined as normal cognitive function or MCI after 7 years with exclusion of those who had progression from normal to MCI.

RESULTS

Eighty patients died during follow-up, 12 patients refused further participation. After 7 years, 109 completed follow-up of whom 40 (37%) were diagnosed with MCI and 24 (22%) with dementia. Of the 64 patients diagnosed with CI, 9 were subclassified with degenerative cognitive disease, 13 with vascular disease, and 42 had mixed cognitive disease. In all, 65 patients (60%) had a favorable outcome. In multivariable logistic regression analysis, lower age and lower medial temporal lobe atrophy (MTLA) grade on MRI at 12 months were independently associated with a favorable outcome, adjusted OR (95% CI), 0.94 (0.86-0.92), and 0.55 (0.35-0.85), respectively.

CONCLUSIONS

Sixty percent of stroke survivors have a favorable cognitive outcome. Lower age and lower MTLA grade on MRI were associated with favorable outcome.

The Loss in Expectation of Life due to Early-Onset Mild Cognitive Impairment and Early-Onset Dementia in Norway

INTRODUCTION

Whether patients with early-onset dementia have poorer or improved survival compared with those with a late onset largely depends on the survival measure. Survival estimates for early-onset mild cognitive impairment (MCI) diagnosis are particularly scarce. We aimed to estimate life expectancy (LE) in patients with early-onset dementia or early MCI, and loss in expectation of life (LEL) for these groups. Comparisons were made with the general Norwegian population and a subgroup of patients with late-onset dementia.

METHODS

Early onset was defined as receiving a diagnosis of MCI or dementia before age 65 years. LE and LEL were predicted using flexible parametric survival models. Our study population was comprised of newly diagnosed (incident) cases (n = 4,906), aged 50-90 years at the time of diagnosis (672 were diagnosed before age 65 years, of which 291 were diagnosed with dementia), in the Norwegian register of persons assessed for cognitive symptoms (NorCog) between 2009 and 2017, and patients were followed up for mortality or censorship until January 2018.

RESULTS

Among the early-onset patients, 8 and 23% died during follow-up, in the MCI and dementia groups, respectively. Both early-onset MCI and especially early-onset dementia were associated with lower LE than in the general Norwegian population; LE for 60-year-old women in 2016 was 26 years in the general population, 20 years in MCI patients, and 7 years in dementia patients. The corresponding LE at 80 years was 10, 6, and 5 years. Thus, LEL were particularly pronounced for patients with early dementia. The diagnosis-specific LE pattern in men was similar to that in women.

DISCUSSION

Early-onset MCI was associated with substantial life years lost (5-6 years), but the loss was particularly pronounced for those with early-onset dementia, reducing the expected life length by 2 decades.

Prevalence and Incidence of Mild Cognitive Impairment across Subtypes, Age, and Sex

OBJECTIVE

The purpose of this study was to report on the prevalence and incidence of mild cognitive impairment (MCI) across age, sex, and subtypes according to various criteria in a population-based sample.

METHODS

The sample was drawn from the Swedish Good Aging in Skåne (GÅS) population study, and data from 3,752 participants aged 60 years and more were used to calculate the MCI prevalence. The incidence was calculated using 2,093 participants with 6-year follow-up data. MCI was defined according to the expanded Mayo Clinic criteria: cognitive complaint, objective cognitive impairment (two different criteria depending on the severity of impairment), preserved functional abilities, and no dementia.

RESULTS

The prevalence estimates ranged from 5.13 to 29.9% depending on age and severity of impairment. The incidence rates of overall MCI were 22.6 (95% confidence interval [CI]: 19.6-25.9) and 8.67 (95% CI: 7.0-10.7) per 1,000 person-years for less severe and severe cognitive impairment, respectively. The highest prevalence and incidence estimates were found for "non-amnestic MCI single domain." The older age groups had a higher prevalence, and no sex or age differences in MCI incidence were detected.

CONCLUSION

Our findings concur with previous research advocating that MCI is a heterogeneous concept, since the prevalence and incidence estimates differed substantially according to age, MCI subtype, and severity of cognitive impairment.

Factors affecting reversion from mild cognitive impairment to normal cognition in midlife to later life in Korea: A national population study

AIM

The purpose of this study was to identify the midlife and later life factors affecting reversion from mild cognitive impairment to normal cognition after 4 years.

METHODS

We analyzed data from the 2012 and 2016 Korean Longitudinal Study of Aging. The participants of this study were Korean community-dwelling adults aged ≥45 years who showed mild cognitive impairment in 2012. They were divided into midlife (<65 years) and later life (≥65 years) based on their age in 2012. Cognitive function was assessed by the Korean Mini-Mental State Examination in 2016. Multiple logistic regression analysis was carried out to determine the factors affecting reversion by age group.

RESULTS

Among participants with mild cognitive impairment, 52.0% in midlife and 26.6% in later life reverted to normal cognition after 4 years. In midlife, higher education (OR 1.97, 95% CI 1.15-3.36), fewer chronic diseases (OR 0.78, 95% CI 0.61-0.99), lower levels of depressive symptoms (OR 0.95, 95% CI 0.90-0.99) and higher participation in social activities (OR 1.91, 95% CI 1.27-2.87) were significantly associated with reversion. In later life, higher baseline cognitive function (OR 1.30, 95% CI 1.14-1.47) and higher participation in social activities (OR 1.35, 95% CI 1.02-1.79) were significantly associated with reversion.

CONCLUSIONS

The reversion rate in midlife was higher than that of later life. More modifiable factors affecting reversion were found in midlife, suggesting that assessment and intervention at an early age should be considered. Geriatr Gerontol Int 2019; 19: 1129-1135.

Functional ability is associated with higher adherence to behavioral interventions in mild cognitive impairment

Objective: Behavioral interventions during early memory decline hold promise in delaying the development of dementia. In the present study, participants in a multimodal behavioral intervention study were assessed for post-intervention adherence and predictors of adherence.Methods: Participants (N = 272, mean age = 75.04 ± 7.54) diagnosed with amnestic Mild Cognitive Impairment (aMCI) were assigned to intervention groups receiving four out of five behavioral intervention components, including yoga, memory compensation training, computerized cognitive training, support groups, and/or wellness education. Length of the intervention was 10 days, 4 h per day, with post-intervention follow-up at 6, 12, and 18 months.Results: Two-hundred and thirty-seven participants completed the 6-month post-intervention follow-up measures, 228 participants completed the 12-month measures, and 218 participants completed the 18-month measures. Participants fully adhered to a mean of 2 out of the 4 taught intervention components. Eighty-nine percent of participants were at least partially adherent to one or more taught intervention components at 6-, 12-, and 18-month post-intervention follow-up. Physical activity was the most adhered to intervention while group support was the least adhered to intervention across all three follow-up time-points. Higher educational level, higher baseline depressive symptoms, higher baseline global cognitive functioning, and better baseline and concurrent functional abilities were associated post-intervention adherence.Conclusion: Changes in functional abilities are associated with disease progression among persons with aMCI. In the present study, individuals with aMCI who have higher education, higher depressive symptoms, and better baseline functioning abilities are more likely to adhere to behavioral intervention components over time. Post-intervention adherence also associates with concurrent daily function.

Factors for predicting reversion from mild cognitive impairment to normal cognition: A meta-analysis

OBJECTIVE

Subjects with mild cognitive impairment (MCI) may revert to normal cognition (NC), but predictive factors are under study. We therefore sought to identify factors which could help in predicting reversion from MCI to NC.

METHODS

Relevant studies were retrieved from PubMed, EMBASE, Cochrane Library, MEDLINE, Web of Science, EBSCO, and OVID. According to the inclusion and exclusion criteria, high-quality assessments of relevant literatures were conducted, followed by data extraction and meta-analysis with Stata 12.0 software.

RESULTS

A total of 17 studies with 6829 participants were included in the meta-analysis. The overall reversion rate is 27.57%. Positive predictive factors were found in younger age (SMD = -0.345, 95% CI, -0.501 to -0.189), higher education level (SMD = 0.337, 95% CI, 0.117-0.558), no APOE ε4 allele (OR = 0.728, 95% CI, 0.575-0.922), no hypertension (OR = 0.826, 95% CI, 0.692-0.987), no stroke (OR = 0.696, 95% CI, 0.507-0.953), and higher Mini-Mental State Examination (MMSE) score (SMD = 0.707, 95% CI, 0.461-0.953).

CONCLUSION

Individuals who are at young age, have higher education level and MMSE score, and have no APOEe4 allele, no hypertension, and no stroke had a high probability to revert from MCI to NC.

Distinct Neural Correlates of Executive Function by Amyloid Positivity and Associations with Clinical Progression in Mild Cognitive Impairment

PURPOSE

This study aimed to identify the neural basis of executive function (EF) in amnestic mild cognitive impairment (aMCI) according to beta-amyloid (Aβ) positivity. Furthermore, we explored if the identified brain areas could serve as predictors for clinical progression.

MATERIALS AND METHODS

We included individuals with aMCI using data from [¹⁸F]-florbetapir-positron emission tomography (PET), fluorodeoxyglucose-PET, and EF scores, as well as follow-up clinical severity scores at 1 and 5 years from baseline from the Alzheimer's Disease Neuroimaging Initiative database. The correlations between EF score and regional cerebral glucose metabolism (rCMglc) were analyzed separately for aMCI with low Aβ burden (aMCI Aβ-, n=230) and aMCI with high Aβ burden (aMCI Aβ+, n=268). Multiple linear regression analysis was conducted to investigate the associations between rCMglc and clinical progression.

RESULTS

Longitudinal courses differed between aMCI Aβ- and aMCI Aβ+ groups. On average, aMCI Aβ- subjects maintained their level of clinical severity, whereas aMCI Aβ+ subjects showed progression. EF impairment in aMCI Aβ- was related to the anterior cingulate cortex (ACC), whereas that in aMCI Aβ+ was related to Alzheimer's Disease-vulnerable brain regions. ACC and the posterior cingulate cortex were associated with clinical progression in aMCI Aβ- and aMCI Aβ+, respectively.

CONCLUSION

Our findings suggest that although MCI subjects showed similar behavioral phenotypes at the time of diagnosis, EF and further progression were associated with different brain regions according to Aβ burden. Clarification of the etiologies and nature of EF impairment in aMCI are critical for disease prognosis and management.

MCI-to-normal reversion using neuropsychological criteria in the Alzheimer's Disease Neuroimaging Initiative

INTRODUCTION

The low mild cognitive impairment (MCI) to cognitively normal (CN) reversion rate in the Alzheimer's Disease Neuroimaging Initiative (2-3%) suggests the need to examine reversion by other means. We applied comprehensive neuropsychological criteria (NP criteria) to determine the resulting MCI to CN reversion rate.

METHODS

Participants with CN (n = 641) or MCI (n = 569) were classified at baseline and year 1 using NP criteria. Demographic, neuropsychological, and Alzheimer's disease biomarker variables as well as progression to dementia were examined across stable CN, reversion, and stable MCI groups.

RESULTS

NP criteria produced a one-year reversion rate of 15.8%. Reverters had demographics, Alzheimer's disease biomarkers, and risk-of-progression most similar to the stable CN group and showed the most improvement on neuropsychological measures from baseline to year 1.

DISCUSSION

NP criteria produced a reversion rate that is consistent with, albeit modestly improved from, reversion rates in meta-analyses. Reverters' biomarker profiles and progression rates suggest that NP criteria accurately tracked with underlying pathophysiologic status.

The impact of behavioral interventions on cognitive function in healthy older adults: A systematic review

Behavioral interventions to improve cognitive function in older adults are widespread and can vary from theater classes to cognitive training programs. However, the effectiveness in maintaining different cognitive domains varies greatly both across and within intervention types. To date, no systematic reviews have synthesized findings across more than a few types of interventions (e.g., cognitive vs. exercise). This systematic review examined 11 types of behavioral interventions and the respective transfer to 19 cognitive domains, as well as transfer to everyday function. Study inclusion criteria were: peer-reviewed articles in English, samples of healthy adults aged 65 and older, and randomized controlled trials of behavioral interventions with reported cognitive outcomes. The 2017 search yielded 75 eligible articles comprising cognitive training, exercise training, combination interventions, cognitively-stimulating activities, and action video games. In general, process- (n = 26) and strategy-based (n = 16) cognitive training improved the trained domains but had weak transfer to non-trained domains. Aerobic training (n = 13) most consistently improved executive function, and strength/resistance (n = 8) and aerobic/resistance combination training (n = 6) most consistently improved cognitive inhibition and visual working memory. Combination interventions (n = 15 nonfactorial, n = 3 factorial) showed promise in improving verbal delayed recall and executive function. Few studies examined cognitively-stimulating activities or action video games, leaving inconclusive results about their effect on cognitive function. Few studies examined everyday function (n = 9), however, process- and strategy-based training demonstrated notable long-term transfer. Recommendations for future research and practice are highlighted.

Neuropsychiatric Symptoms and the Diagnostic Stability of Mild Cognitive Impairment

BACKGROUND

Mild cognitive impairment (MCI) is an intermediate diagnosis between normal cognition (NC) and dementia, including Alzheimer's disease (AD) dementia. However, MCI is heterogeneous; many individuals subsequently revert to NC while others remain stable at MCI for several years. Identifying factors associated with this diagnostic instability could assist in defining clinical populations and determining cognitive prognoses.

OBJECTIVE

The current study examined whether neuropsychiatric symptoms could partially account for the temporal instability in cognitive diagnoses.

METHOD

The sample included 6,763 participants from the National Alzheimer's Coordinating Center Uniform Data Set. All participants had NC at baseline, completed at least two follow-up visits (mean duration: 5.5 years), and had no recent neurological conditions. Generalized linear models estimated by generalized estimating equations examined associations between changes in cognitive diagnoses and symptoms on the Neuropsychiatric Inventory Questionnaire (NPI-Q) and Geriatric Depression Scale (GDS-15).

RESULTS

1,121 participants converted from NC to MCI; 324 reverted back to NC and 242 progressed to AD dementia. Higher symptoms on the GDS-15 and circumscribed symptom domains on the NPI-Q were associated with conversion from NC to MCI and a decreased likelihood of reversion from MCI to NC. Individuals with higher symptoms on NPI-Q Hyperactivity and Mood items were more likely to progress to AD dementia.

DISCUSSION

The temporal instability of MCI can be partially explained by neuropsychiatric symptoms. Individuals with higher levels of specific symptoms are more likely to progress to AD dementia and less likely to revert to NC. Identification and treatment of these symptoms might support cognitive functioning in older adults.

Reversible predictors of reversion from mild cognitive impairment to normal cognition: a 4-year longitudinal study

BACKGROUND

Although previous studies have revealed many factors related to mild cognitive impairment (MCI) reversion, information about reversible factors related MCI reversion is limited, impeding the development of intervention strategies. The aim of the present study was to examine whether reversible factors such as lifestyle activities are associated with MCI reversion in elderly individuals using the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes database. A total of 396 community-living older adults (age ≥ 65 years) participated in the study. They were classified as reverters or non-reverters from mild cognitive impairment to normal cognition. We assessed lifestyle activities, potential confounding factors of cognitive decline, and reversion of mild cognitive impairment.

RESULTS

In a completed data set of 396 participants, 202 participants (51.0%) reverted from MCI to normal cognition. The reversion rate in participants for whom we imputed data was 34.3%. In the imputed group, a logistic regression model showed that the odds ratios (ORs) for reversion were significantly higher in participants who drove a car (OR 1.50, 95% confidence interval (CI) 1.41-1.60), used a map to travel to unfamiliar places (OR 1.12, 95% CI 1.06-1.18), read books or newspapers (OR 1.54, 95% CI 1.37-1.73), took cultural classes (OR 1.10, 95% CI 1.04-1.15), attended meetings in the community (OR 1.22, 95% CI 1.16-1.28), participated in hobbies or sports activities (OR 1.09, 95% CI 1.03-1.16), and engaged in fieldwork or gardening (OR 1.14, 95% CI 1.08-1.21). The imputed sample showed that non-reverters were more likely to discontinue fieldwork or gardening (11.0% vs. 6.1%) than reverters during the follow-up period.

CONCLUSIONS

Specific lifestyle activities may play important roles in MCI reversion in older adults. The longitudinal data indicate that it is reasonable to recommend that individuals continue to engage in fieldwork or gardening to increase their chance of recovery from MCI.

Reversion From Mild Cognitive Impairment To Normal Cognition: False-Positive Error Or True Restoration Thanks To Cognitive Control Ability?

PURPOSE

Relatively little attention has been paid to the meaning of reversion from mild cognitive impairment (MCI) to cognitively normal (CN), compared to MCI progression studies. The purpose of the study was to investigate the characteristics contributing to reversion from MCI to CN and to identify the associated factors with such reversion.

PATIENTS AND METHODS

We retrospectively identified 200 individuals who initially diagnosed as MCI and completed the second visit from the National Research Center for Dementia (NRCD) registry in Korea. Participants underwent comprehensive clinical and neuropsychological assessments. Factors associated with reversion were examined by a independent-samples t-test, χ² test, and logistic regression. Longitudinal change was examined by a repeated measures analysis of variance (rANOVA).

RESULTS

Based on the second assessment, 78 (39%) individuals were found to have reverted to CN (rMCI) and 118 (59%) remained with MCI (sMCI). Four (2%) progressed to Alzheimer's disease dementia and they were excluded from further analysis. Over a wide range of socio-demographic, clinical, and neuropsychological variables, group difference was significant only in neuropsychological tests of cognitive control. Both groups showed improvement in several neuropsychological tests, implying a practice effect, but the rMCI group showed greater improvement.

CONCLUSION

Reversion from MCI to CN might not be a false-positive error but a true recovery from cognitive impairment. Our results suggest that cognitive control ability may be a characteristic favorable for the restoration of cognitive function. Therefore, assessment of cognitive control might facilitate the development of appropriate interventions for MCI as well as prognosis evaluation.

Mild Cognitive Impairment that Does Not Progress to Dementia: A Population-Based Study

BACKGROUND/OBJECTIVE

In population studies, most individuals with mild cognitive impairment (MCI) do not progress to dementia in the near term, but rather remain stable MCI or revert to normal cognition. Here, we characterized MCI subgroups with different outcomes over 5 years.

SETTING/PARTICIPANTS

A population-based cohort (N=1603).

MEASUREMENTS

Clinical Dementia Rating (CDR); self-reported medical conditions, subjective cognitive concerns, self-rated health, depressive symptoms, blood pressure, medications, blood pressure, APOE genotype, cognitive domain composite scores.

DESIGN

We compared 3 MCI subgroups who progressed to dementia (n=86), stabilized at MCI (n=384), or reverted to normal (n=252), to those who remained consistently normal (n=881), defining MCI as CDR = 0.5 and dementia as CDR≥1. Using multinomial logistic regression models adjusted for demographics, we examined the associations of each group with selected baseline characteristics.

RESULTS

With the normal group for reference, worse subjective cognitive concerns, functional impairments, self-rated health, and depressive symptoms were associated with being in any MCI group. Taking more prescription medications was associated with being in the stable MCI and reverter groups; diabetes and low diastolic blood pressure were associated with stable MCI. The APOE4 genotype was associated with stable and progressive MCI; stroke was associated with progressive MCI. All MCI subgroups were likely to have lower mean composite scores in all cognitive domains and more operationally defined impairments in attention, language, and executive function; reverters were more likely to lack memory and visuospatial impairments.

CONCLUSIONS

MCI subgroups with different 5-year outcomes had some distinct characteristics suggesting different underlying causes. The progressors, unlike the reverters, had a profile broadly typical of Alzheimer's disease; the stable MCIs had other, including vascular, morbidity. These data shed light on the heterogeneity of MCI in the population. J Am Geriatr Soc 67:232-238, 2019.

Diagnostic and prognostic role of semantic processing in preclinical Alzheimer's disease

Relatively spared during most of the timeline of normal aging, semantic memory shows a subtle yet measurable decline even during the pre-clinical stage of Alzheimer's disease. This decline is thought to reflect early neurofibrillary changes and impairment is detectable using tests of language relying on lexical-semantic abilities. A promising approach is the characterization of semantic parameters such as typicality and age of acquisition of words, and propositional density from verbal output. Seminal research like the Nun Study or the analysis of the linguistic decline of famous writers and politicians later diagnosed with Alzheimer's disease supports the early diagnostic value of semantic processing and semantic memory. Moreover, measures of these skills may play an important role for the prognosis of patients with mild cognitive impairment.