The economics of mild cognitive impairment

Estimating global prevalence of mild cognitive impairment and dementia in elderly with overweight, obesity, and central obesity: A systematic review and meta-analysis

BACKGROUND AND AIM

Previous studies have demonstrated that adiposity, particularly obesity during midlife, may have a detrimental effect on cognitive function. This study aims to estimate the global prevalence of mild cognitive impairment (MCI) and dementia in elderly aged 60 years or above with overweight, obesity, and central obesity.

METHODS

We searched PubMed, Embase, Web of Science, and Cochrane Library from inception to November 2023. DerSimonian-Laird random-effects model with Logit transformation was used. Sensitivity analysis, meta-regression, and subgroup analysis were employed to investigate determinants of the prevalence of MCI and dementia.

RESULTS

A total of 72 studies involving 2,980,947 elderly with distinct adiposity status were included. Pooled prevalence of MCI and dementia in elderly with overweight and obesity was 32.54% and 9.47%, respectively. Univariate meta-regression analysis indicated that the heterogeneity in dementia prevalence was attributable to variations in study size (R2 = 0.01, p < 0.05), while the multivariable analysis underscored that the income of country or area had the most significant predictive importance (60.3% and 90.3%) for both MCI and dementia prevalence. Subgroup analysis revealed regional disparities and diagnostic technique variations contributing to heterogeneity. Based on currently available but inadequate epidemiological data, the pooled prevalence of MCI and dementia in elderly with central obesity was calculated as 10.18% and 9.75%, respectively.

CONCLUSION

Strategies to address adiposity-associated cognitive impairment should consider multifaceted interventions beyond simple weight reduction. Macro-level initiatives such as improvement of income levels and micro-level interventions including the adoption of accurate diagnostic techniques also represent equally pivotal components.

Targeting Cognitive Resilience through Prebiotics: A Focused Perspective

This perspective article is a product of the work of an expert group within the Prebiotic Task Force convened by the International Life Sciences Institute Europe, a non-profit organization that brings together experts from academia, industry, and public service to catalyze nutrition science for public benefit. An expert group was conceived in October 2023 to discuss the evidence base on the use of prebiotics to promote cognitive functioning, with a focus on highlighting knowledge gaps and proposing a list of recommendations to guide this specific area of research forward. To address this, we evaluated existing systematic reviews and meta-analyses of human intervention studies that examine the effects of prebiotics on cognitive functioning. These are predominantly conducted in healthy participants under basal conditions and have, to date, revealed limited effects. In this perspective, we propose that prebiotics should be investigated as agents to promote cognitive resilience by testing their effects on cognitive performance under certain cognition-taxing factors that individuals encounter across their lifespan. These include stress, poor sleep outcomes, sedentary behavior, and unhealthy dietary patterns, all of which have been shown to be associated with altered microbiome and impact global cognition or specific cognitive domains. In addition, we recommend identifying vulnerable populations that are either subclinical or that struggle chronically or periodically with 1 or more cognition-taxing factors, to better uncover the boundary conditions for prebiotic effectiveness. By broadening the scope of research to include diverse populations and challenging conditions in daily life or experimental settings, we can expand our understanding of the role of prebiotics not only in cognitive health or impairment, but also as potential preventative agents that may promote cognitive resilience during aging and in response to various lifestyle-related challenges.

Association between low cognitive performance and diabetes-related health indicators across racial and ethnic groups in adults with diabetes

AIM

To examine the associations between low cognitive performance (LCP) and diabetes-related health indicators (including body mass index [BMI], HbA1c, systolic blood pressure [SBP], low-density lipoprotein [LDL] and self-reported poor physical health) and whether these associations vary across racial/ethnic subgroups.

METHODS

We identified adults aged 60 years or older with self-reported diabetes from the 2011-2014 National Health and Nutrition Examination Survey. Individuals with cognitive test scores in the lowest quartile were defined as having LCP. We used regression models to measure the associations of LCP with diabetes-related biometrics (BMI, HbA1c, SBP and LDL); and self-reported poor physical health. Moreover, we explored potential variations in these associations across racial/ethnic subgroups.

RESULTS

Of 873 (261 with LCP) adults with diabetes, LCP was associated with higher HbA1c, SBP and LDL (adjusted difference: 0.41%, 5.01 mmHg and 5.08 mg/dL, respectively; P < .05), and greater odds of reporting poor physical health (adjusted odds ratio: 1.59, P < .05). The association between LCP and HbA1c was consistent across racial/ethnic groups, and notably pronounced in Hispanic and Other. BMI worsened with LCP, except for non-Hispanic Black. Excluding the Other group, elevated SBP was observed in people with LCP, with Hispanic showing the most significant association. LDL levels were elevated with LCP for Hispanic and Other. Physical health worsened with LCP for both non-Hispanic Black and Hispanic.

CONCLUSIONS

We quantified the association between LCP and diabetes-related health indicators. These associations were more pronounced in Hispanic and Other racial/ethnic groups.

Efficacy of anti-amyloid-ß monoclonal antibody therapy in early Alzheimer's disease: a systematic review and meta-analysis

BACKGROUND

Studies targeting amyloid-ß in patients with Alzheimer's disease (AD) have conflicting results and early initiation of therapy may yield better outcomes.

METHODS

We systematically searched PubMed, Embase, Cochrane Library, and Clinicaltrials.gov for randomized trials comparing monoclonal antibodies (mAbs) with placebo in MCI or mild dementia due to AD.

RESULTS

Nineteen studies comprising 15,275 patients were included. In patients with early AD, mAbs reduced the rate of decline, in both the Clinical Dementia Rating Scale, the sum of boxes (CDR-SB; MD -0.30; 95% CI -0.42,-0.19; p < 0.01), and the Alzheimer's Disease Assessment Scale, cognitive subscore (ADAS-cog; SMD -0.80; 95% CI -10.25,-0.35; p < 0.01). The results were similar between clinical stages for CDR-SB (MCI, MD -0.19; 95% CI -0.35,-0.03; p = 0.02; mild dementia, MD -0.45; 95% CI -0.65,-0.25; p < 0.01; subgroup differences, p = 0.13), as well as for ADAS-Cog (MCI, SMD -0.83; 95% CI -1.49,-0.17; p = 0.01; mild dementia, SMD -0.69; 95% CI -1.32 to -0.05; p = 0.03; subgroup differences, p = 0.47). The risk of amyloid-related imaging abnormalities (ARIA) was significantly higher in patients taking mAbs, including ARIA-edema (RR 7.7; 95% CI 4.60 to 13.00; p < 0.01), ARIA-hemorrhage (RR 1.8; 95% CI 1.22 to 2.59; p < 0.01), and symptomatic or serious ARIA (RR 14.1; 95% CI 7.30 to 27.14; p < 0.01).

CONCLUSION

Anti-amyloid-ß mAbs attenuate cognitive and functional decline compared with placebo in early AD; whether the magnitude of this effect is clinically important remains uncertain, especially relative to the safety profile of these medications. Starting immunotherapy in patients with MCI was not significantly different than starting in the mild dementia stage.

PROSPERO REGISTRY

CRD42023430698.

The Effectiveness of Dance Interventions on Psychological and Cognitive Health Outcomes Compared with Other Forms of Physical Activity: A Systematic Review with Meta-analysis

BACKGROUND

Physical activity is known to improve psychological and cognitive outcomes. Learning dance sequences may challenge cognition, partnered or group dance may benefit social interactions, and the artistic aspect may improve psychological wellbeing. Dance is an equally effective form of physical activity compared with other structured physical activities to improve physical health, but it is unclear how effective dance could be for psychological and cognitive outcome measures.

OBJECTIVE

To systematically review the literature on the effectiveness of structured dance interventions, compared with structured exercise programmes, on psychological and cognitive outcomes across the lifespan.

METHODS

Eight databases were searched from earliest records to July 2022. Studies investigating a dance intervention lasting ≥ 4 weeks, including psychological and/or cognitive health outcomes, and having a structured exercise comparison group were included. Screening and data extraction were performed by two independent reviewers at all stages. All reviewer disagreements were resolved by the primary author. Where appropriate, meta-analysis was performed, or an effect size estimate generated.

RESULTS

Of 21,737 records identified, 27 studies met the inclusion criteria. Total sample size of included studies was 1392 (944 females, 418 males, 30 unreported). Dance was equally as effective as other physical activity interventions in improving quality of life for people with Parkinson's disease [mean difference 3.09; 95% confidence interval (CI) - 2.13 to 8.30; p = 0.25], reducing anxiety (standardised mean difference 2.26; 95% CI - 2.37 to 6.90; p = 0.34), and improving depressive symptoms (standardised mean difference 0.78; 95% CI - 0.92 to 2.48; p = 0.37). Preliminary evidence found dance to be superior to other physical activity interventions to improve motivation, aspects of memory, and social cognition and to reduce distress. Preliminary evidence found dance to be inferior to other physical activity interventions to improve stress, self-efficacy and language fluency.

CONCLUSION

Undertaking structured dance of any genre is generally equally and occasionally more effective than other types of structured exercise for improving a range of psychological and cognitive outcomes.

TRIAL REGISTRATION

PROSPERO: CRD42018099637.

Increased serum methylmalonic acid levels were associated with the presence of cognitive dysfunction in older chronic kidney disease patients with albuminuria

BACKGROUND

This study aimed to evaluate the correlation between serum methylmalonic acid (MMA) levels and cognition function in patients with chronic kidney disease (CKD).

METHODS

In this cross-sectional study, we included 537 CKD individuals aged ≥ 60-year-old with albuminuria from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Four cognitive tests including the Digit Symbol Substitution Test (DSST), the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Delayed Recall and Word Learning tests, and the Animal Fluency test (AF) were performed. Associations between MMA and cognition scores were assessed with linear regression models.

RESULTS

MMA level was negatively associated with residual renal function and nutrition status. After multivariate adjustment, elevated serum MMA levels were independently correlated with decline of cognition in CKD patients with albuminuria.

CONCLUSION

Our study showed that higher serum MMA levels were independently associated with the presence of cognition dysfunction in CKD patients. The exact pathogenesis of MMA and cognition needs further research.

The Relation of Sleep Characteristics and Cognitive Impairment in Community-Dwelling Middle-Aged and Older Adults: Ardakan Cohort Study on Aging (ACSA)

Introduction

The rise in the elderly population has brought attention to mild cognitive impairment (MCI). Sleep disorders also affect many older adults, indicating an important area of research for disturbed sleep and faster brain aging. This population-based study aimed to investigate the association of several sleep indicators with cognitive performance.

Methods

This cross-sectional study focused on adults over 50 in the Ardakan Cohort Study on Aging (ACSA). MCI was evaluated using the Mini-Mental State Examination (MMSE) and the Abbreviated Mental Test score (AMTS) in literate and illiterate individuals. Sleep characteristics were collected using the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, and Berlin questionnaire. The logistic regression models were used to analyze the data.

Results

Overall, 3,380 literate and 1,558 illiterate individuals were included. In both groups, participants with MCI had a significantly higher PSQI global score (p < 0.05). Also, among the literate individuals, a significantly higher risk of having sleep-disordered breathing and poor sleep quality was observed in participants with MCI (p < 0.05). In illiterate individuals, higher sleep latency than 15 min increased odds of MCI (p < 0.05). However, after adjusting for all variables, only literate individuals with a sleep duration of more than 8 h had 66 percent increased odds of having MCI (p = 0.033).

Conclusion

Sleep duration might be associated with cognitive function in the older Iranian population. Our findings underscore the importance of considering sleep patterns in relation to cognitive health.

Lifestyle factors as mediators of area-level socioeconomic differentials in mental health and cognitive function: the Tromsø Study

INTRODUCTION

Low socioeconomic status (SES) is associated with poor mental health and cognitive function. Individual-level SES and area-level SES (ASES) may affect mental health and cognitive function through lifestyle. We aimed to quantify the associations of ASES with mental health and cognitive function and examine the mediating role of lifestyle behaviours independent of individual-level SES in a Norwegian population.

METHODS

In this cross-sectional study, we included 7211 participants (54% women) from the seventh survey of the Tromsø Study (2015-2016) (Tromsø7). The exposure variable ASES was created by aggregating individual-level SES variables (education, income, housing ownership) from Statistics Norway at the geographical subdivision level. Tromsø7 data were used as mediators (smoking, snuff, alcohol, physical activity, diet) and outcomes (cognitive function, anxiety, depression, insomnia). Mediation and mediated moderation analysis were performed with age as a moderator, stratified by sex.

RESULTS

Higher ASES was associated with better cognitive function and fewer depression and insomnia symptoms, independent of individual-level SES. These associations were mediated by smoking and physical activity. Alcohol was a mediator for depression and cognitive function in women. Age was a significant moderator of the association between ASES and global cognitive function in women. The largest total indirect effect of ASES was found for depression, with the joint effect of the mediators accounting for 36% of the total effect.

CONCLUSIONS

People living in areas with lower ASES are at higher risk of poor mental health, such as depression and insomnia, and have lower cognitive function possibly due to unhealthy lifestyle (smoking, alcohol and physical inactivity).

Explainable Machine Learning with Pairwise Interactions for Predicting Conversion from Mild Cognitive Impairment to Alzheimer's Disease Utilizing Multi-Modalities Data

BACKGROUND

Predicting cognition decline in patients with mild cognitive impairment (MCI) is crucial for identifying high-risk individuals and implementing effective management. To improve predicting MCI-to-AD conversion, it is necessary to consider various factors using explainable machine learning (XAI) models which provide interpretability while maintaining predictive accuracy. This study used the Explainable Boosting Machine (EBM) model with multimodal features to predict the conversion of MCI to AD during different follow-up periods while providing interpretability.

METHODS

This retrospective case-control study is conducted with data obtained from the ADNI database, with records of 1042 MCI patients from 2006 to 2022 included. The exposures included in this study were MRI biomarkers, cognitive scores, demographics, and clinical features. The main outcome was AD conversion from aMCI during follow-up. The EBM model was utilized to predict aMCI converting to AD based on three feature combinations, obtaining interpretability while ensuring accuracy. Meanwhile, the interaction effect was considered in the model. The three feature combinations were compared in different follow-up periods with accuracy, sensitivity, specificity, and AUC-ROC. The global and local explanations are displayed by importance ranking and feature interpretability plots.

RESULTS

The five-years prediction accuracy reached 85% (AUC = 0.92) using both cognitive scores and MRI markers. Apart from accuracies, we obtained features' importance in different follow-up periods. In early stage of AD, the MRI markers play a major role, while for middle-term, the cognitive scores are more important. Feature risk scoring plots demonstrated insightful nonlinear interactive associations between selected factors and outcome. In one-year prediction, lower right inferior temporal volume (<9000) is significantly associated with AD conversion. For two-year prediction, low left inferior temporal thickness (<2) is most critical. For three-year prediction, higher FAQ scores (>4) is the most important. During four-year prediction, APOE4 is the most critical. For five-year prediction, lower right entorhinal volume (<1000) is the most critical feature.

CONCLUSIONS

The established glass-box model EBMs with multimodal features demonstrated a superior ability with detailed interpretability in predicting AD conversion from MCI. Multi features with significant importance were identified. Further study may be of significance to determine whether the established prediction tool would improve clinical management for AD patients.

Does (re-)entering the labour market at advanced ages protect against cognitive decline? A matching difference-in-differences approach

BACKGROUND

While prolonged labour market participation becomes increasingly important in ageing societies, evidence on the impacts of entering or exiting work beyond age 65 on cognitive functioning is scarce.

METHODS

We use data from two large population-representative data sets from South Korea and the USA to investigate and compare the effects of the labour market (re-)entry and exit by matching employment and other confounder trajectories prior to the exposure. We chose the Korean Longitudinal Study of Aging (N=1872, 2006-2020) for its exceptionally active labour participation in later life and the Health and Retirement Study (N=4070, 2006-2020) for its growing inequality among US older adults in labour participation. We use the matching difference-in-differences (DID) method, which allows us to make causal claims by reducing biases through matching.

RESULTS

We find general positive effects of entering the labour market in South Korea (DID estimate: 0.653, 95% CI 0.167 to 1.133), while in the USA such benefit is not salient (DID estimate: 0.049, 95% CI -0.262 to 0.431). Exiting the late-life labour market leads to cognitive decline in both South Korea (DID estimate: -0.438, 95% CI -0.770 to -0.088) and the USA (DID estimate: -0.432, 95% CI -0.698 to -0.165).

CONCLUSIONS

Findings suggest that Korean participants cognitively benefited from late-life labour market participation, while US participants did not. Differences in participant characteristics and reasons for labour market participation may have led to the differential findings. We found the negative effects of exiting the late-life labour force in both countries.

Eye-tracking paradigms for the assessment of mild cognitive impairment: a systematic review

Mild cognitive impairment (MCI), representing the 'transitional zone' between normal cognition and dementia, has become a novel topic in clinical research. Although early detection is crucial, it remains logistically challenging at the same time. While traditional pen-and-paper tests require in-depth training to ensure standardized administration and accurate interpretation of findings, significant technological advancements are leading to the development of procedures for the early detection of Alzheimer's disease (AD) and facilitating the diagnostic process. Some of the diagnostic protocols, however, show significant limitations that hamper their widespread adoption. Concerns about the social and economic implications of the increasing incidence of AD underline the need for reliable, non-invasive, cost-effective, and timely cognitive scoring methodologies. For instance, modern clinical studies report significant oculomotor impairments among patients with MCI, who perform poorly in visual paired-comparison tasks by ascribing less attentional resources to novel stimuli. To accelerate the Global Action Plan on the Public Health Response to Dementia 2017-2025, this work provides an overview of research on saccadic and exploratory eye-movement deficits among older adults with MCI. The review protocol was drafted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Electronic databases were systematically searched to identify peer-reviewed articles published between 2017 and 2022 that examined visual processing in older adults with MCI and reported gaze parameters as potential biomarkers. Moreover, following the contemporary trend for remote healthcare technologies, we reviewed studies that implemented non-commercial eye-tracking instrumentation in order to detect information processing impairments among the MCI population. Based on the gathered literature, eye-tracking-based paradigms may ameliorate the screening limitations of traditional cognitive assessments and contribute to early AD detection. However, in order to translate the findings pertaining to abnormal gaze behavior into clinical applications, it is imperative to conduct longitudinal investigations in both laboratory-based and ecologically valid settings.

The effects of herbal medicine (Jujadokseo-hwan) on quality of life in patients with mild cognitive impairment: Cost-effectiveness analysis alongside randomized controlled trial

Background

Mild cognitive impairment (MCI), the early stage of dementia, requires effective intervention for symptom management and improving patients' quality of life (QoL). Jujadokseo-hwan (JDH) is a Korean herbal medicine prescription used to improve MCI symptoms, such as memory deficit. This study evaluates the improvement in QoL through JDH. Alongside a clinical trial, it estimates the cost-effectiveness of JDH, compared to placebo, for MCI over 24 weeks.

Methods

Changes in QoL were measured using the EuroQol-5 Dimensions (EQ-5D) and Korean version QoL-Alzheimer's Disease (KQOL-AD). Direct medical and non-medical costs were surveyed and incremental cost-effectiveness ratios (ICER) per QALY for JDH were produced.

Results

In total, 64 patients were included in the economic evaluation (n = 35 in JDH, n = 29 in placebo). In the JDH group, EQ-5D and KQOL-AD improved by 0.020 (p = .318) and 3.40 (p = .011) over 24 weeks, respectively. In the placebo group, they increased by 0.001 (p=.920) and 1.07 (p=.130), respectively. The ICER was KRW 76,400,000 per QALY and KRW 108,000 per KQOL-AD for JDH, compared to the placebo group.

Conclusion

JDH is not considered a cost-effective treatment option compared with placebo; however, it positively affects QoL improvement in patients with MCI.

Acupuncture on mild cognitive impairment: A systematic review of neuroimaging studies

Mild cognitive impairment (MCI) is a multifactorial and complex central neurodegenerative disease. Acupuncture appears to be an effective method for cognitive function improvement in MCI patients. Neural plasticity remaining in the MCI brain implies that acupuncture-associated benefits may not be limited to the cognitive function. Instead, neurological alternations in the brain play a vital role in corresponding to the cognitive improvement. However, previous studies have mainly focused on the effects of cognitive function, leaving neurological findings relatively unclear. This systematic review summarized existing studies that used various brain imaging techniques to explore the neurological effect regarding acupuncture use for MCI treatment. Potential neuroimaging trials were searched, collected, and identified independently by two researchers. Four Chinese databases, four English databases, and additional sources were searched to identify studies reporting the use of acupuncture for MCI from the inception of databases until 1 June 2022. Methodological quality was appraised using the Cochrane risk-of-bias tool. In addition, general, methodological, and brain neuroimaging information was extracted and summarized to investigate the potential neural mechanisms by which acupuncture affects patients with MCI. In total, 22 studies involving 647 participants were included. The methodological quality of the included studies was moderate to high. The methods used included functional magnetic resonance imaging, diffusion tensor imaging, functional near-infrared spectroscopy, and magnetic resonance spectroscopy. Acupuncture-induced brain alterations observed in those patients with MCI tended to be observable in the cingulate cortex, prefrontal cortex, and hippocampus. The effect of acupuncture on MCI may play a role in regulating the default mode network, central executive network, and salience network. Based on these studies, researchers could extend the recent research focus from the cognitive domain to the neurological level. Future researches should develop additional relevant, well-designed, high-quality, and multimodal neuroimaging researches to detect the effects of acupuncture on the brains of MCI patients.

Using dynamic microsimulation to project cognitive function in the elderly population

BACKGROUND

A long-term projection model based on nationally representative data and tracking disease progression across Alzheimer's disease continuum is important for economics evaluation of Alzheimer's disease and other dementias (ADOD) therapy.

METHODS

The Health and Retirement Study (HRS) includes an adapted version of the Telephone Interview for Cognitive Status (TICS27) to evaluate respondents' cognitive function. We developed an ordered probit transition model to predict future TICS27 score. This transition model is utilized in the Future Elderly Model (FEM), a dynamic microsimulation model of health and health-related economic outcomes for the US population. We validated the FEM TICS27 model using a five-fold cross validation approach, by comparing 10-year (2006-2016) simulated outcomes against observed HRS data.

RESULTS

In aggregate, the distribution of TICS27 scores after ten years of FEM simulation matches the HRS. FEM's assignment of cognitive/mortality status also matches those observed in HRS on the population level. At the individual level, the area under the receiver operating characteristic (AUROC) curve is 0.904 for prediction of dementia or dead with dementia in 10 years, the AUROC for predicting significant cognitive decline in two years for mild cognitive impairment patients is 0.722.

CONCLUSIONS

The FEM TICS27 model demonstrates its predictive accuracy for both two- and ten-year cognitive outcomes. Our cognition projection model is unique in its validation with an unbiased approach, resulting in a high-quality platform for assessing the burden of cognitive decline and translating the benefit of innovative therapies into long-term value to society.

The association of sleep and cortical thickness in mild cognitive impairment

We investigated whether device-measured sleep parameters are associated with cortical thickness in older adults with probable mild cognitive impairment (MCI). We performed a cross-sectional, exploratory analysis of sleep and structural MRI data. Sleep data were collected with MotionWatch8© actigraphy over 7 days. We computed average and variability for sleep duration, sleep efficiency, and fragmentation index. T1-weighted MRI scans were used to measure cortical thickness in FreeSurfer. We employed surface-based analysis to determine the association between sleep measures and cortical thickness, adjusting for age, sex, Montreal Cognitive Assessment (MoCA) score, and sleep medication use. Our sample included 113 participants (age = 73.1 [5.7], female = 72 [63.7 %]). Higher fragmentation index variability predicted lower cortical thickness in the left superior frontal gyrus (cluster size = 970.9 mm², cluster-wise p = 0.017, cortical thickness range = 2.1 mm² to 3.0 mm²), adjusting for age, sex, MoCA, and sleep medication. Our results suggest that higher variability in sleep fragmentation, an indicator of irregular sleep pattern, is linked to lower cortical thickness. Future longitudinal studies are needed to determine the directionality of these associations.

Do Mini-Mental State Examination and Montreal Cognitive Assessment predict high-cost health care users? A competing risks analysis in The Irish Longitudinal Study on Ageing

OBJECTIVES

Policymakers want to better identify in advance the 10% of people who account for approximately 75% of health care costs. We evaluated how well Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) predicted high costs in Ireland.

METHODS/DESIGN

We used five waves from The Irish Longitudinal Study on Ageing, a biennial population-representative survey of people aged 50+ (2010-2018). We used competing risks analysis where our outcome of interest was "high costs" (top 10% at any wave) and the competing outcome was dying or loss to follow-up without first having the high-cost outcome. Our binary predictors of interest were a 'low score' (bottom 10% in the sample) in MMSE (≤25 pts) and MoCA (≤19 pts) at baseline, and we calculated sub-hazard ratios after controlling for sociodemographic, clinical and functional factors.

RESULTS

Of 5856 participants, 1427 (24%) had the 'high cost' outcome; 1463 (25%) had a competing outcome; and 2966 (51%) completed eight years of follow-up without either outcome. In multivariable regressions a low MoCA score was associated with high costs (SHR: 1.38 (95% CI: 1.2-1.6) but a low MMSE score was not. Low MoCA score at baseline had a higher true positive rate (40%) than did low MMSE score (35%). The scores had similar association with exit from the study.

CONCLUSIONS

MoCA had superior predictive accuracy for high costs than MMSE but the two scores identify somewhat different types of high-cost user. Combining the approaches may improve efforts to identify in advance high-cost users.

Psychometric Properties and Measurement Invariance of the Chinese Version of the Brief Assessment of Impaired Cognition Questionnaire in Community-Dwelling Older Adults

This study aimed to verify the Chinese version of the Brief Assessment of Impaired Cognition Questionnaire (C-BASIC-Q), and provide a new tool for the future large-scale epidemiological investigation of cognitive function in China. From March to May 2021, a cross-sectional study of 2,144 Chinese community-dwelling older adults (men = 1,075, mean age = 72.01 years, SD = 6.96 years, ranging from 60–99 years) was conducted in Jinan. Exploratory and confirmatory factor analyses were performed to evaluate the factor structure of the C-BASIC-Q. Convergent validity was evaluated by correlations with the Mini-Mental State Examination (MMSE). Internal consistency and test-retest reliability were evaluated using Cronbach's alpha and retest correlations in a sub-sample (n = 129). Linear regression was used to analyze the impact of demographic factors on the MMSE and C-BASIC-Q scores. Measurement invariance was evaluated using a multi-group confirmatory factor analysis. The mean C-BASIC-Q score was 15.94 (SD = 3.43). Factor analysis suggested a three-factor structure of C-BASIC-Q (self-report, orientation, and informant report). The C-BASIC-Q score was significantly positively associated with the MMSE score, showing good convergent validity. Cronbach's alpha of the C-BASIC-Q was 0.862, and the test-retest correlation coefficient was significant (r = 0.952, p < 0.001), indicating good internal consistency and test-retest reliability. Measurement invariance analysis showed that C-BASIC-Q had configural, metric, and scalar invariance across sex, age, residence, education level and marital status. C-BASIC-Q was less affected by age, residence, education, and marital status than the MMSE. In summary, the C-BASIC-Q had good reliability, validity, and measurement invariance, and is a valid tool for evaluating cognitive functioning in Chinese community-dwelling older adults.

Protective effects of camellia and olive oils against cognitive impairment via gut microbiota-brain communication in rats

Food intake influences neurofunction via the gut microbiota-brain axis. Monounsaturated fatty acid (MUFA) consumption is highly associated with neuroprotection; the mechanism behind the effects of olive oil and camellia oil on gut microbiota remains unclear. In this study, the objective was to compare the neuroprotective role of oleic acid-rich camellia oil and olive oil against AlCl₃-induced mild cognitive impairment (MCI) in rats. Morris water maze tests revealed that learning and memory capacities improved in AlCl₃-induced rats subjected to camellia oil administration better than olive oil treatment. Moreover, the results showed that the camellia oil- and olive oil-treated AlCl₃-induced rat groups had significantly reduced oxidative stress and inflammatory cytokines. Notably, Spearman correlation analysis indicated that the inflammatory cytokines negatively correlated with the microbial strains (Bacteroides pectinophilus_group and Blautia) in response to camellia oil administration. Furthermore, Ruminococcaceae_UCG014 abundance was significantly enhanced by camellia oil intake, which was highly positively associated with antioxidant activity expression. In conclusion, the novel data suggest that the outcomes of camellia oil consumption were superior to those of olive oil intake as camellia oil may have a beneficial effect on MCI protection and improvement through the gut microbiota-brain communication.

Finger Tapping as a Biomarker to Classify Cognitive Status in 80+-Year-Olds

This study examined the association between finger tapping and cognitive function in a group of 225 elderly participants (116 males; age 79–92 years; M = 82.5; SD = 2.4). Finger tapping was assessed in two conditions: self-selected pace and fast pace. Based on cognitive assessments, including the MoCA and CERA-NP test battery, participants were classified as cognitively healthy individuals (CHI), participants with mild cognitive impairments (MCI), and those with possible MCI (pMCI). Results of the analyses show significant differences between groups, sex and the group × sex interaction in four parameters for the self-selected pace condition and eight parameters for the fast pace condition. These parameters were used for classification by means of linear discriminant analysis (LDA). The first LDA component showed significant differences between CHI and pMCI and between CHI and MCI. Furthermore, the second LDA component showed significant differences between CHI and pMCI as well as between pMCI and MCI. Nevertheless, the algorithm correctly classified only 50% of participants, regardless of group, suggesting that tapping parameters are only partially useful for classification in early stages of dementia. We discuss these findings in terms of the diadochokinetic nature of finger tapping as associated with the age-related degeneration of cortical and subcortical motor areas.

Cognitive Function in a Sleep Clinic Cohort of Patients with Obstructive Sleep Apnea

Rationale: Obstructive sleep apnea (OSA) is associated with an increased risk of mild cognitive impairment (MCI) within the general population. However, MCI risk in sleep-clinic populations of patients with OSA is poorly characterized.Objectives: To determine the prevalence of MCI in a sleep-clinic population of patients with OSA and which patients are at the greatest risk for this complication.Methods: Adults (n = 1,084) referred to three academic sleep centers for suspected OSA who had home sleep apnea testing or in-laboratory polysomnography were recruited. Patients completed sleep and medical history questionnaires, the Montreal Cognitive Assessment Test (MoCA) of global cognition, the Rey Auditory Verbal Learning Test of memory, and the Wechsler Adult Intelligence Scale-Fourth Edition Digit-Symbol Coding (DSC) subtest of information processing speed.Results: A MoCA score <26 (range 0-30) was operationally defined as MCI. MCI was present in 47.9% of our entire patient cohort, increasing to >55.3% in patients with moderate and severe OSA. Patients with a MoCA <26 were predominantly older males with more severe OSA, hypoxemia, and vascular comorbidities. Moderate and severe OSA were independently associated with >70% higher odds for MCI compared with patients with no OSA (P = 0.003). Memory and information processing speed was lower than age-matched normal values (P < 0.001), with lower MoCA and DSC scores associated with a higher oxygen desaturation index and nocturnal hypoxemia.Conclusions: Cognitive impairment is highly prevalent in patients referred to sleep clinics for suspected OSA, occurring predominantly in older males with moderate to severe OSA and concurrent vascular comorbidities. Moderate to severe OSA is an independent risk factor for MCI.

Low-Frequency Transcranial Magnetic Stimulation (LF-TMS) in Treating Depression in Patients With Impaired Cognitive Functioning

OBJECTIVE

Common methodologies for treating depressive symptoms have demonstrated decreased efficacy among individuals with impaired cognitive functioning. While transcranial magnetic stimulation (TMS) has been approved to treat major depressive disorder, few studies have analyzed the ability of TMS to treat depressive symptoms among individuals with cognitive impairments. The present study had two objectives: to determine whether low-frequency TMS (LF-TMS) might demonstrate efficacy in treating depressive symptoms among individuals with impaired cognitive functioning; and to determine whether LF-TMS might improve neurocognitive functioning above and beyond depressive symptom improvements.

METHODS

Data were derived from a pre-existing database at Eastern Virginia Medical School. Fifty-three (N=53) participants completed LF-TMS treatment. The Beck Depression Inventory II (BDI-II) and CNS Vital Signs (CNS-VS) neurocognitive assessment were administered at multiple time points throughout treatment. Participants were classified as impaired cognitive functioning or average cognitive functioning based on baseline CNS-VS scores. Data were analyzed using restricted maximum likelihood (REML) measures-within-persons longitudinal hierarchical linear modeling (HLM) with time-varying covariates.

RESULTS

LF-TMS produced significant reductions in depressive symptoms for individuals in both cognitive functioning groups; however, a significant group-by-time interaction indicates differential effects between these two groups. Low-frequency TMS produced significant improvements in three neurocognitive domains above and beyond improvements in depressive symptoms; however, the reliability of these changes may be questionable.

CONCLUSIONS

This study adds to the growing body of empirical findings for LF-TMS treatment in improving neurocognitive functioning above and beyond other treatment-related effects.

Psychometric Evaluation and Workflow Integration Study of a Tablet-Based Tool to Detect Mild Cognitive Impairment in Older Adults: Protocol for a Mixed Methods Study

BACKGROUND

With the rapid aging of the global population, experts anticipate a surge in the prevalence of mild cognitive impairment (MCI) and dementia worldwide. It is argued that developing more sensitive, easy to administer, and valid MCI screening tools for use in primary care settings may initiate timely clinical and personal care planning and treatment, enabling early access to programs and services. Including functional competence measures in screening tests makes them more ecologically valid and may help to identify cognitive deficits at an earlier stage.

OBJECTIVE

We aim to conduct a preliminary evaluative study comparing the sensitivity, specificity, and reliability of the BrainFx Screen (referred to as SCREEN hereafter), a novel digital tool designed to assess functional competence and detect early signs of cognitive impairment, with the Quick Mild Cognitive Impairment, a validated and highly sensitive tool that detects MCI in the older adult population. We will also investigate the perceived usefulness and integration of the SCREEN into primary care practice to identify demonstrable impacts on clinical workflow and health care providers' (HCP) perceptions of its success as a screening tool. Patients' perceptions of completing the SCREEN and its impact on their quality of life will also be explored.

METHODS

This study has a concurrent, mixed methods, prospective, and quasi-experimental design. Participants will be recruited from 5 primary care family health teams (FHTs; defined by multidisciplinary practice and capitated funding) across southwestern Ontario, Canada. Participants will include HCPs, patients, care partners, and FHT administrative executives. Patients 55 years and older with no history of diagnoses for MCI, dementia, or Alzheimer disease rostered in one of the FHTs participating in the study will be eligible to participate. Their care partners will help triangulate the qualitative data collected from patients. Participating FHTs will identify an occupational therapist from their site to participate in the study; this HCP will both administer the research protocol and participate in semistructured in-depth interviews and questionnaires. Principal component analysis will be conducted on the SCREEN data to understand the test components better. Tests comparing sensitivity, specificity, and test-retest reliability will assess the validity of SCREEN as a screening tool for MCI.

RESULTS

This paper describes the study protocol and its activities to date. Data collection was halted early because of COVID-19 restrictions on research activity, and data analysis is currently in progress.

CONCLUSIONS

At the end of the project, we anticipate having an initial comparative evaluation of the SCREEN as a tool for early detection of MCI in primary care older adult patient populations. Resource constraints on this research study limit our ability to conduct a randomized controlled trial; however, the results will assist developers of the SCREEN in determining whether rigorous controlled testing is warranted.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/25520.

The Long-Term Efficacy of Working Memory Training in Healthy Older Adults: A Systematic Review and Meta-Analysis of 22 Randomized Controlled Trials

OBJECTIVES

The long-lasting efficacy of working memory (WM) training has been a controversial and still ardently debated issue. In this meta-analysis, the authors explored the long-term effects of WM training in healthy older adults on WM subdomains and abilities outside the WM domain assessed in randomized controlled studies.

METHOD

A systematic literature search of PubMed, Web of Science, PsycINFO, Cochrane Library, ProQuest, clinicaltrials.gov, and Google Scholar was conducted. Random-effects models were used to quantitatively synthesize the existing data.

RESULTS

Twenty-two eligible studies were included in the meta-analysis. The mean participant age ranged from 63.77 to 80.1 years. The meta-synthesized long-term effects on updating were 0.45 (95% confidence interval = 0.253-0.648, <6 months: 0.395, 0.171-0.619, ≥6 months: 0.641, 0.223-1.058), on shifting, 0.447 (0.246-0.648, <6 months: 0.448, 0.146-0.75, ≥6 months: 0.446, 0.176-0.716); on inhibition, 0.387 (0.228-0.547, <6 months: 0.248, 0.013-0.484, ≥6 months: 0.504, 0.288-0.712); on maintenance, 0.486 (0.352-0.62, <6 months: 0.52, 0.279-0.761, ≥6 months: 0.471, 0.31-0.63).

DISCUSSION

The results showed that WM training exerted robust long-term effects on enhancing the WM system and improving processing speed and reasoning in late adulthood. Future studies are needed to use different tasks of the same WM construct to evaluate the WM training benefits, to adopt more ecological tasks or tasks related to daily life, to improve the external validity of WM training, and to identify the optimal implementation strategy for WM training.

Improving outcomes for people with mild cognitive impairment: An Australian mixed-methods pilot study

OBJECTIVE

This pilot study tested the feasibility and acceptability of an innovative functional task exercise program to ameliorate mild cognitive impairment.

METHODS

The functional task exercise program was trialled on community-dwelling adults aged 60 years or older. The 10-week program was conducted in regional Australia and evaluated for acceptability and feasibility. Outcomes were assessed pre- and post- intervention and at three-month follow-up. Structured interviews were conducted with caregivers and participants at the end of the program.

RESULTS

Acceptability was demonstrated, with approximately 80% of the 23 participants completing the program. Clinical improvements were demonstrated in several cognitive and functional measures using an uncontrolled pre-post test design. Qualitative findings suggest feasibility as the program was viewed positively by participants and caregivers.

CONCLUSION

The functional exercise program was acceptable, was feasible and improved outcomes in an Australian context. Research is urgently needed to identify and treat people with mild cognitive impairment living in the community.

Informal Caregiving, Poor Mental Health, and Subjective Cognitive Decline: Results From a Population-Based Sample

The current study examined potential gender differences in the associations between informal caregiving, poor mental health, and subjective cognitive decline (SCD). Data were obtained from the U.S. Behavioral Risk Factor Surveillance System (N = 16,042; 9,410 women, 6,632 men). Multivariate linear and logistic regression models were used to obtain adjusted βs and odds ratios (ORs), and 95% confidence intervals (CIs) depicting the association between informal caregiving, poor mental health, and SCD overall and by gender. Caregiving was positively associated with poor mental health among men (adjusted β = 2.60; 95% CI [2.59, 2.62]) and women (adjusted β = 0.40; 95% CI [0.23, 0.57]). Poor mental health was positively associated with SCD among men (adjusted OR = 1.05; 95% CI [1.02, 1.08]) and women (adjusted OR = 1.07; 95% CI [1.04, 1.10]). Poor mental health may be associated with SCD, irrespective of gender, and additional studies are needed that will identify key variables influencing SCD among male and female informal caregivers. [Journal of Gerontological Nursing, 46(12), 31-41.].

Observation of Patient and Caregiver Burden Associated with Early Alzheimer's Disease in the United States: Design and Baseline Findings of the GERAS-US Cohort Study1

Background:

Alzheimer’s disease (AD) is one of the costliest diseases in the United States.

Objective:

To describe aspects of real-world patient and caregiver burden in patients with clinician-diagnosed early AD, including mild cognitive impairment (MCI) and mild dementia (MILD) due to AD.

Methods:

Cross-sectional assessment of GERAS-US, a 36-month cohort study of patients seeking care for early AD. Eligible patients were categorized based on study-defined categories of MCI and MILD and by amyloid positivity [+] or negativity [–] within each severity cohort. Demographic characteristics, health-related outcomes, medical history, and caregiver burden by amyloid status are described.

Results:

Of 1,198 patients with clinician-diagnosed early AD, 52% were amyloid[+]. For patients in both cohorts, amyloid[–] was more likely to occur in those with: delayed time to an AD-related diagnosis, higher rates of depression, poorer Bath Assessment of Subjective Quality of Life in Dementia scores, and Hispanic/Latino ethnicity (all p < 0.05). MILD[–] patients (versus MILD[+]) were more medically complex with greater rates of depression (55.7% versus 40.4%), sleep disorders (34.3% versus 26.5%), and obstructive pulmonary disease (11.8% versus 6.6%); and higher caregiver burden (Zarit Burden Interview) (all p < 0.05). MILD[+] patients had lower function according to the Functional Activities Questionnaire (p < 0.001), yet self-assessment of cognitive complaints across multiple measures did not differ by amyloid status in either severity cohort.

Conclusions:

Considerable patient and caregiver burden was observed in patients seeking care for memory concerns. Different patterns emerged when both disease severity and amyloid status were evaluated underscoring the need for further diagnostic assessment and care for patients.

Study Registry:

H8A-US-B004; ClinicalTrials.gov: NCT02951598.

A feasibility study on the association between residential greenness and neurocognitive function in middle-aged Bulgarians

Recent research has indicated that exposure to residential vegetation ("greenness") may be protective against cognitive decline and may support the integrity of the corresponding brain structures. However, not much is known about these effects, especially in less affluent countries and in middle-aged populations. In this study, we investigated the associations between greenness and neurocognitive function. We used a convenience sample of 112 middle-aged Bulgarians and two cognitive tests: the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Battery (CERAD-NB) and the Montreal Cognitive Assessment (MoCA). In addition, structural brain imaging data were available for 25 participants. Participants' home address was used to link cognition scores to the normalised difference vegetation index (NDVI), a measure of overall neighbourhood vegetation level (radii from 100 to 1,000 m). Results indicated that higher NDVI was consistently associated with higher CERAD-NB and MoCA scores across radial buffers and adjustment scenarios. Lower waist circumference mediated the effect of NDVI on CERAD-NB. NDVI100-m was positively associated with average cortical thickness across both hemispheres, but these correlations turned marginally significant (P<0.1) after correction for false discovery rate due to multiple comparisons. In conclusion, living in a greener neighbourhood might be associated with better cognitive function in middle-aged Bulgarians, with lower central adiposity partially accounting for this effect. Tentative evidence suggests that greenness might also contribute to structural integrity in the brain regions regulating cognitive functions. Future research should build upon our findings and investigate larger and more representative population groups.

A Birth Cohort Analysis of Amnestic Mild Cognitive Impairment Incidence in the Einstein Aging Study (EAS) Cohort

BACKGROUND

The transition from normal cognition to Alzheimer's disease is considered a continuum, with amnestic mild cognitive impairment (aMCI) an intermediate clinical cognitive state. Although prior work suggests that dementia incidence rates may be declining, there is little information regarding temporal trends in aMCI incidence.

OBJECTIVE

To determine whether age specific rates of aMCI have changed over sequential birth cohorts among individuals included in the population-based Einstein Aging Study (EAS) cohort. A secondary objective was to examine trends in aMCI rates among Blacks and Whites and by sex.

METHODS

Age specific incidence of aMCI was examined by birth year among 1,233 individuals age 70 years and above enrolled in the population-based EAS cohort between November 1, 1993 and February 22, 2016 and who had at least one annual follow-up assessment (5,321 person years of follow-up). Poisson regression was used to determine whether there has been a change in age specific aMCI rates over sequential years of birth.

RESULTS

No significant change in aMCI rates was identified in the overall cohort, among Blacks or Whites, or among males or females born between 1899 and 1946.

CONCLUSIONS

Despite a trend for decreased dementia incidence in the EAS cohort, rates of incident aMCI have not changed. These apparently conflicting results may indicate a delay or decrease in the rates of transition from aMCI to dementia within the cohort. However, further studies are needed to confirm whether rates of aMCI have changed in other populations, and how aMCI rates are related to secular trends in dementia risk factors.

Relationship Between Treatment Initiation and Healthcare Costs in Alzheimer's Disease

The relationship between Alzheimer's disease (AD) treatment patterns and healthcare costs is unknown. Administrative claims data from the MarketScan Commercial and Medicare databases covering 2010 through 2016 were used to identify the comorbidities, treatment patterns, and healthcare costs in the three years prior to and one year post medical diagnosis of AD in 21,448 patients with no treatment and 57,970 patients with treatment. Pre-index mean annual costs ranged from $14,228 to $26,876, and post-index mean annual costs ranged from $21,052 to $45,685 depending on age and treatment timing. After adjusting for baseline characteristics, patients 50-100 years old who initiated treatment with an FDA approved drug prior to or concurrent with diagnosis had healthcare costs 9%-19% lower in the year following diagnosis than those who did not receive treatment. Early or concurrent treatment is associated with lower overall healthcare costs in the year following AD diagnosis.

Identifying Adaptive and Maladaptive Behaviors Following a Diagnosis of Mild Cognitive Impairment

INTRODUCTION

Individual reactions to a diagnosis of mild cognitive impairment (MCI) can vary in a wide range of both adaptive and maladaptive responses. Understanding such reactions to diagnosis is important to maximize adaptive responses that can promote continued independence.

METHODS

In this pilot study, the Aging and Memory Quality of Life survey was developed to facilitate an understanding of adaptive and maladaptive behaviors results from a diagnosis of MCI. The Aging and Memory Quality of Life was administered to 45 individuals diagnosed with MCI and 45 cognitively normal participants serving as control subjects matched for age, sex, and education. Study partners were surveyed to collect corroborating and or discrepant observer responses.

RESULTS

Inconsistent with study partners' reporting, MCI subjects may be underreporting physical limitations, and overreporting medication compliance. MCI subjects identified challenges to managing financial affairs.

DISCUSSION

Developing strategies to circumvent the development of maladaptive behaviors could significantly reduce morbidity and mortality in MCI patients.

International Mind, Activities and Urban Places (iMAP) study: methods of a cohort study on environmental and lifestyle influences on brain and cognitive health

INTRODUCTION

Numerous studies have found associations between characteristics of urban environments and risk factors for dementia and cognitive decline, such as physical inactivity and obesity. However, the contribution of urban environments to brain and cognitive health has been seldom examined directly. This cohort study investigates the extent to which and how a wide range of characteristics of urban environments influence brain and cognitive health via lifestyle behaviours in mid-aged and older adults in three cities across three continents.

METHODS AND ANALYSIS

Participants aged 50-79 years and living in preselected areas stratified by walkability, air pollution and socioeconomic status are being recruited in Melbourne (Australia), Barcelona (Spain) and Hong Kong (China) (n=1800 total; 600 per site). Two assessments taken 24 months apart will capture changes in brain and cognitive health. Cognitive function is gauged with a battery of eight standardised tests. Brain health is assessed using MRI scans in a subset of participants. Information on participants' visited locations is collected via an interactive web-based mapping application and smartphone geolocation data. Environmental characteristics of visited locations, including the built and natural environments and their by-products (e.g., air pollution), are assessed using geographical information systems, online environmental audits and self-reports. Data on travel and lifestyle behaviours (e.g., physical and social activities) and participants' characteristics (e.g., sociodemographics) are collected using objective and/or self-report measures.

ETHICS AND DISSEMINATION

The study has been approved by the Human Research Ethics Committee of the Australian Catholic University, the Institutional Review Board of the University of Hong Kong and the Parc de Salut Mar Clinical Research Ethics Committee of the Government of Catalonia. Results will be communicated through standard scientific channels. Methods will be made freely available via a study-dedicated website.

TRIAL REGISTRATION NUMBER

ACTRN12619000817145.

Physical activity for cognitive health: what advice can we give to older adults with subjective cognitive decline and mild cognitive impairment?

Subjective cognitive decline (SCD) and mild cognitive impairment (MCI) are common conditions in older age and are associated with an increased risk of future cognitive decline and dementia. As there is currently no effective pharmacological treatment available for SCD and MCI, modifiable risk factors for cognitive decline and dementia have received increasing attention in the literature as a focus for clinical trials. Physical activity (PA) is one of the strongest protective lifestyle factors. This clinical review aims to highlight the accumulating evidence about the benefits of PA for SCD and MCI. Whilst there is agreement that at least 150 minutes of moderate aerobic PA per week in combination with additional resistance training is necessary to support brain health in people with SCD and MCI, future research is required to help inform specific advice on type of exercise, intensity, “dose” and effective strategies to encourage behavior change.

Sensor-based systems for early detection of dementia (SENDA): a study protocol for a prospective cohort sequential study

Background

Dementia and cognitive decline are serious social and economic burdens. An increase in the population of older people, as well as longer lifespans mean that numbers of dementia cases are exponentially rising. Neuropathological changes associated with dementia are thought to appear before the clinical manifestation of cognitive symptoms, i.e., memory impairments. Further, some older adults (OA) experience cognitive decline before it can be objectively diagnosed. For optimal care of these patients, it is necessary to detect cognitive decline and dementia at an early stage. In this vein, motor, sensory, and neurophysiological declines could be promising factors if found to be present before the onset of cognitive impairment. Hence, the objective of the SENDA study is to develop a multi-dimensional sensor-based instrument that allows early detection of cognitive decline or dementia in OA with the help of cognitive, sensory, motor, and neurophysiological parameters before its clinical manifestation.

Methods/design

In the cohort sequential study, participants are assigned to one of three study groups depending on their cognitive status: 1. cognitively healthy individuals (CHI), 2. subjectively cognitively impaired persons (SCI), or 3. (possible) mildly cognitively impaired persons (pMCI, MCI). All groups take part in the same cognitive (e.g., executive function tests), motor (e.g., gait analyses, balance tests), sensory (e.g., vibration perception threshold test, proprioception tests), and neurophysiological (e.g., electroencephalograms) measurements. Depending on the time at which participants are included into the study, all measurements are repeated up to four times in intervals of 8 months within 3 years to identify associations with cognitive changes over time.

Discussion

This study aims to detect possible motor, sensory, neurophysiological, and cognitive predictors to develop an early screening tool for dementia and its pre-stages in OA. Thus, affected persons could receive optimal health care at an earlier time point to maintain their health resources.

Trial status

The study is ongoing. The recruitment of participants will be continued until May 2020.

Total Synthesis of Galanthamine and Lycoramine Featuring an Early-Stage C-C and a Late-Stage Dehydrogenation via C-H Activation

Herein, we report a novel strategy toward galanthamine and lycoramine. The concise synthesis was enabled by a Rh-catalyzed gram-scale C-C activation for the tetracyclic carbon framework and a regioselective Pd-catalyzed C-H activation for double-bond introduction. An aqueous-phase Beckmann rearrangement was performed for nitrogen atom insertion. Galanthamine and lycoramine were completed in 11 and 10 steps, respectively.

Herpes Simplex Virus Type-1 Infection: Associations with Inflammation and Cognitive Aging in Relation to Schizophrenia

Most persons experience cognitive decline as they grow older. The term "cognitive aging," coined to describe milder varieties of cognitive decline, is likely to be due to multiple causes. Persistent or repeated infections of the central nervous system (whether subclinical or diagnosable) can cause damage to neurons directly or indirectly through inflammation resulting in incremental neuronal damage, thus eroding cognitive reserve. This possibility has not been considered widely. We evaluated the data linking persistent infection with herpes simplex virus type 1 (HSV-1) and cognitive aging by applying the Bradford Hill criteria. Despite inherent problems in establishing causal relations for chronic disorders, our analyses suggest plausible links. These studies are pertinent for patients with schizophrenia, who are particularly vulnerable due to disorder-related cognitive impairment. Further investigations are warranted to test a causal hypothesis, particularly prospective studies and intervention studies.

Novel AChE and BChE inhibitors using combined virtual screening, text mining and in vitro binding assays

In the current work, we developed a computational pipeline method for predicting the binding affinities of studied compounds at the specific target sites. Since many approved therapeutic compounds involve indole or indole-derivative rings, in the current study we focused compounds including these fingerprints. Initially, 212520 compounds were retrieved from Specs-SC library and after the conversion of IUPAC text file format, compounds that include 'indol' keyword (5194 compounds) were used in binary QSAR-based models to screen against a defined therapeutic activity "Alzheimer's disease" (AD). The molecules that have higher AD therapeutic activity values (>0.5) were then used in the 26 different toxicity-QSAR models. Binary QSAR models resulted 89 hits that have high AD therapeutic activity and no toxicity. Selected 89 molecules were then screened against acetylcholinesterase (AChE) targets using molecular docking and top-docking poses of compounds were used in initially short (10 ns) molecular dynamics (MD) simulations. Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) binding free energy calculations were performed for 89 ligands and tightly bound 17 ligands based on average MM/GBSA scores were selected for long (100 ns) MD simulations. The same protocol was also applied for the known 4 AChE inhibitors. Selected hits were also docked to the binding pocket of butyrylcholinesterase (BChE). Finally, based on MM/GBSA scores, as well as their corresponding docking scores and metabolite production profiles, 7 compounds were selected and their in vitro tests were performed. Out of 7 compounds, 6 of them showed μM-level inhibition for both AChE and BChE targets.Communicated by Ramaswamy H. Sarma.

The Clinical Utility of the TYM and RBANS in a One-Stop Memory Clinic in Singapore: A Pilot Study

BACKGROUND

We aimed to examine the discriminant validity of a brief self-administered cognitive screening test, the Test Your Memory (TYM) and a brief neuropsychological test, the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), supplemented with executive and language tests (Color Trail Test [CTT] and modified Boston Naming Test [mBNT], respectively), in detecting cognitive impairment (CI) in a one-stop memory clinic in Singapore.

METHODS

Ninety patients ≥50 years old with a diagnosis of no cognitive impairment, mild cognitive impairment, and mild Alzheimer disease were recruited from memory clinic. They received the TYM, Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), RBANS, CTT, mBNT, and a gold-standard formal neuropsychological test battery.

RESULTS

The TYM had a significantly larger area under the curve (AUC) than MMSE (0.96 vs 0.88, P = .03) and was equivalent to MoCA in detecting CI (0.96 vs 0.95, P = .80). At the optimal cutoff points, the TYM (<38) was significantly more sensitive than the MMSE (<24) and MoCA (<20; P < .001). The RBANS had an AUC equivalent to the RBANS supplemented with CTT and mBNT (0.92 vs 0.86, P = .22) in detecting CI. The RBANS supplemented with CTT and mBNT was more sensitive than RBANS alone in detecting CI (sensitivity: 0.98 vs 0.93, P = .016) among patients screened negative using TYM.

CONCLUSION

The self-administered TYM is superior to MMSE and equivalent to MoCA in detecting CI and could be implemented routinely. The RBANS supplemented with CTT and mBNT is more sensitive in detecting CI than RBANS alone therefore could be used for diagnostic purposes.

Longitudinal Associations of Sensory and Cognitive Functioning: A Structural Equation Modeling Approach

Objectives

Although visual and hearing impairments have been found to be associated with cognitive decline in the old age, the mechanism underlying this relationship remains unclear. This study aimed at assessing the predictive role of visual and hearing difficulties on subsequent cognitive functioning.

Method

From the cohort of the first (2002) and fifth waves (2010) of the English Longitudinal Study of Ageing (ELSA), 3,508 individuals aged 60 and older were included in the study. Five self-reported visual and hearing functioning items were used to assess sensory functioning at baseline. Cognition was assessed 8 years later by means of four measured tests covering immediate and delayed recall, verbal fluency, and processing speed. A Multiple Indicators Multiple Causes approach was used to assess the longitudinal associations of visual and hearing functioning with cognitive difficulties. A multigroup longitudinal measurement invariance was used to estimate latent change in cognitive difficulties across groups of participants presenting either visual, hearing, or dual sensory impairment (i.e., those reporting difficulties in both visual and hearing functioning items).

Results

Visual (β = 0.140, p < .001) and hearing (β = 0.115, p < .001) difficulties predicted cognitive difficulties 8 years later. The latent increase in cognitive difficulties was steeper in people with visual impairment (d = 0.52, p < .001), hearing impairment (d = 0.50, p < .001), and dual-sensory impairment (d = 0.68, p < .001) than those non-impaired (d = 0.12, p < .001).

Discussion

Visual and hearing difficulties were identified as predictors of subsequent cognitive decline in the old age. Interventions to prevent visual and hearing difficulties may have a substantial impact to slow down subsequent age-related cognitive decline.

Leisure-time physical activity sustained since midlife and preservation of cognitive function: The Atherosclerosis Risk in Communities Study

INTRODUCTION

We tested the hypotheses that higher levels of and persistence of midlife leisure-time physical activity (LTPA) are associated long-term with lower cognitive decline and less incident dementia.

METHODS

A total of 10,705 participants (mean age: 60 years) had LTPA (no, low, middle, or high) measured in 1987-1989 and 1993-1995. LTPA was assessed in relation to incident dementia and 14-year change in general cognitive performance.

RESULTS

Over a median follow-up of 17.4 years, 1063 dementia cases were observed. Compared with no LTPA, high LTPA in midlife was associated with lower incidence of dementia (hazard ratio [95% confidence interval], 0.71 [0.61, 0.86]) and lower declines in general cognitive performance (-0.07 standard deviation difference [-0.12 to -0.04]). These associations were stronger when measured against persistence of midlife LTPA over 6 years.

DISCUSSION

LTPA is a readily modifiable factor associated inversely with long-term dementia incidence and cognitive decline.

Automated Multiclass Classification of Spontaneous EEG Activity in Alzheimer's Disease and Mild Cognitive Impairment

The discrimination of early Alzheimer’s disease (AD) and its prodromal form (i.e., mild cognitive impairment, MCI) from cognitively healthy control (HC) subjects is crucial since the treatment is more effective in the first stages of the dementia. The aim of our study is to evaluate the usefulness of a methodology based on electroencephalography (EEG) to detect AD and MCI. EEG rhythms were recorded from 37 AD patients, 37 MCI subjects and 37 HC subjects. Artifact-free trials were analyzed by means of several spectral and nonlinear features: relative power in the conventional frequency bands, median frequency, individual alpha frequency, spectral entropy, Lempel–Ziv complexity, central tendency measure, sample entropy, fuzzy entropy, and auto-mutual information. Relevance and redundancy analyses were also conducted through the fast correlation-based filter (FCBF) to derive an optimal set of them. The selected features were used to train three different models aimed at classifying the trials: linear discriminant analysis (LDA), quadratic discriminant analysis (QDA) and multi-layer perceptron artificial neural network (MLP). Afterwards, each subject was automatically allocated in a particular group by applying a trial-based majority vote procedure. After feature extraction, the FCBF method selected the optimal set of features: individual alpha frequency, relative power at delta frequency band, and sample entropy. Using the aforementioned set of features, MLP showed the highest diagnostic performance in determining whether a subject is not healthy (sensitivity of 82.35% and positive predictive value of 84.85% for HC vs. all classification task) and whether a subject does not suffer from AD (specificity of 79.41% and negative predictive value of 84.38% for AD vs. all comparison). Our findings suggest that our methodology can help physicians to discriminate AD, MCI and HC.

Nursing Home Use Across The Spectrum of Cognitive Decline: Merging Mayo Clinic Study of Aging With CMS MDS Assessments

BACKGROUND/OBJECTIVES

Objective, complete estimates of nursing home (NH) use across the spectrum of cognitive decline are needed to help predict future care needs and inform economic models constructed to assess interventions to reduce care needs.

DESIGN

Retrospective longitudinal study.

SETTING

Olmsted County, MN.

PARTICIPANTS

Mayo Clinic Study of Aging participants assessed as cognitively normal (CN), mild cognitive impairment (MCI), previously unrecognized dementia, or prevalent dementia (age = 70-89 years; N = 3,545).

MEASUREMENTS

Participants were followed in Centers for Medicare and Medicaid Services (CMS) Minimum Data Set (MDS) NH records and in Rochester Epidemiology Project provider-linked medical records for 1-year after assessment of cognition for days of observation, NH use (yes/no), NH days, NH days/days of observation, and mortality.

RESULTS

In the year after cognition was assessed, for persons categorized as CN, MCI, previously unrecognized dementia, and prevalent dementia respectively, the percentages who died were 1.0%, 2.6%, 4.2%, 21%; the percentages with any NH use were 3.8%, 8.7%, 19%, 40%; for persons with any NH use, median NH days were 27, 38, 120, 305, and median percentages of NH days/days of observation were 7.8%, 12%, 33%, 100%. The year after assessment, among persons with prevalent dementia and any NH use, >50% were a NH resident all days of observation. Pairwise comparisons revealed that each increase in cognitive impairment category exhibited significantly higher proportions with any NH use. One-year mortality was especially high for persons with prevalent dementia and any NH use (30% vs 13% for those with no NH use); 58% of all deaths among persons with prevalent dementia occurred while a NH resident.

CONCLUSIONS

Findings suggest reductions in NH use could result from quality alternatives to NH admission, both among persons with MCI and persons with dementia, together with suitable options for end-of-life care among persons with prevalent dementia.

Informing Understandings of Mild Cognitive Impairment for Older Adults: Implications From a Scoping Review

The development of effective interventions for mild cognitive impairment (MCI) in older adults has been limited by extensive variability in the conceptualization and definition of MCI, its subtypes, and relevant diagnostic criteria within the neurocultural, pharmaceutical, and gerontological communities. A scoping review was conducted to explore the conceptual development of MCI and identify the resulting ethical, political, and technological implications for the care of older adults with MCI. A comprehensive search was conducted between January and April 2013 to identify English-language peer-reviewed articles published between 1999 and 2013. Our analysis revealed that the MCI conceptual debate remains unresolved, the response to ethical issues is contentious, the policy response is limited, and one-dimensional and technological interventions are scarce. Reflections on the conceptual, ethical, and policy responses in conjunction with the identification of the needs of older adults diagnosed with MCI highlight significant opportunities for technological interventions to effectively reposition MCI in the aging care discourse.

Cognition in chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Cognitive impairment is common in people with chronic kidney disease (CKD) and associated with increased morbidity and mortality. Subtle changes can impact engagement with healthcare, comprehension, decision-making, and medication adherence. We aimed to systematically summarise evidence of cognitive changes in CKD.

METHODS

We searched MEDLINE (March 2016) for cross-sectional, cohort or randomised studies that measured cognitive function in people with CKD (PROSPERO, registration number CRD42014015226). The CKD population included people with eGFR < 60 mL/min/1.73 m², not receiving renal replacement therapy, in any research setting. We conducted a meta-analysis using random effects, expressed as standardised mean differences (SMD) with 95% confidence intervals (CI). Outcomes were performance in eight cognitive domains. Bias was assessed with the Newcastle-Ottawa Scale (NOS).

RESULTS

We identified 44 studies reporting sufficient data for synthesis (51,575 participants). Mean NOS score for cohort studies was 5.8/9 and for cross-sectional 5.4/10. Studies were deficient in NOS outcome and selection due to poor methods reporting and in comparison group validity of demographics and chronic disease status. CKD patients (eGFR < 60 mL/min/1.73 m²) performed worse than control groups (eGFR ≥ 60 mL/min/1.73 m²) on Orientation & Attention (SMD -0.79, 95% CI, -1.44 to -0.13), Language (SMD -0.63, 95% CI, -0.85 to -0.41), Concept Formation & Reasoning (SMD -0.63, 95% CI, -1.07 to -0.18), Executive Function (SMD -0.53, 95% CI, -0.85 to -0.21), Memory (SMD -0.48, 95% CI, -0.79 to -0.18), and Global Cognition (SMD -0.48, 95% CI, -0.72 to -0.24). Construction & Motor Praxis and Perception were unaffected (SMD -0.29, 95% CI, -0.90 to 0.32; SMD -1.12, 95% CI, -4.35 to 2.12). Language scores dropped with eGFR (<45 mL/min/1.73 m² SMD -0.86, 95% CI, -1.25 to -46; 30 mL/min/1.73 m² SMD -1.56, 95% CI, -2.27 to -0.84). Differences in Orientation & Attention were greatest at eGFR < 45 mL/min/1.73 m² (SMD -4.62, 95% CI, -4.68 to -4.55). Concept Formation & Reasoning differences were greatest at eGFR < 45 mL/min/1.73 m² (SMD -4.27, 95% CI, -4.23 to -4.27). Differences in Executive Functions were greatest at eGFR < 30 mL/min/1.73 m² (SMD -0.54, 95% CI, -1.00 to -0.08).

CONCLUSIONS

Cognitive changes occur early in CKD, and skills decline at different rates. Orientation & Attention and Language are particularly affected. The cognitive impact of CKD is likely to diminish patients' capacity to engage with healthcare decisions. An individual's cognitive trajectory may deviate from average.

Blood-Based Oxidative Stress Markers and Cognitive Performance in Early Old Age: The HAPIEE Study

BACKGROUND/AIMS

Oxidative stress is involved in Alzheimer disease pathology, but its impact on cognitive function in community-dwelling older adults remains unknown. We estimated associations between serum oxidative stress markers and cognitive function in early old age.

METHODS

Subjects aged 45-69 years recruited in urban centers in Central and Eastern Europe had memory, verbal fluency, and processing speed assessed at baseline (2002-2005) and 3 years later. Derivatives of reactive oxygen metabolites (d-ROMs), biological antioxidant potential (BAP), and total thiol levels (TTLs) were measured at baseline in a subsample. Linear regression was used to estimate associations of biomarkers with cognitive test scores cross-sectionally (n = 4,304) and prospectively (n = 2,882).

RESULTS

Increased d-ROM levels were inversely associated with global cognition and verbal fluency cross-sectionally and in prospective analysis; observed effects corresponded to 3-4 years' higher age. TTL was inconsistently associated with memory. BAP was not related to cognitive function.

CONCLUSION

This study found modest evidence for a relationship between serum d-ROMs and cognitive function in a population sample of older adults.

A call for comparative effectiveness research to learn whether routine clinical care decisions can protect from dementia and cognitive decline

Common diseases like diabetes, hypertension, and atrial fibrillation are probable risk factors for dementia, suggesting that their treatments may influence the risk and rate of cognitive and functional decline. Moreover, specific therapies and medications may affect long-term brain health through mechanisms that are independent of their primary indication. While surgery, benzodiazepines, and anti-cholinergic drugs may accelerate decline or even raise the risk of dementia, other medications act directly on the brain to potentially slow the pathology that underlies Alzheimer’s and other dementia. In other words, the functional and cognitive decline in vulnerable patients may be influenced by the choice of treatments for other medical conditions. Despite the importance of these questions, very little research is available. The Alzheimer’s Drug Discovery Foundation convened an advisory panel to discuss the existing evidence and to recommend strategies to accelerate the development of comparative effectiveness research on how choices in the clinical care of common chronic diseases may protect from cognitive decline and dementia.

B-vitamins are potentially a cost-effective population health strategy to tackle dementia: Too good to be true?

Introduction

To respond to the threat of dementia to public health and the economy, we need to prioritize research resources on strategies that would be the most effective. In relation to the prevention of dementia, this article considers whether lowering plasma homocysteine by B-vitamin supplementation is one of the top priority and cost-effective treatments.

Method

A decision model was constructed to calculate the lifetime costs and quality-adjusted life years (QALYs) of providing B-vitamin treatment to people in the United Kingdom over 60 years with high levels (>13 μmol/L) of plasma homocysteine, which was compared to the lifetime costs and outcomes of not providing them with the treatment.

Results

Treatment with B-vitamins will save £60,021 per QALY gained and so is highly cost-effective.

Discussion

We anticipate that this provocative finding will be debated by scientists, clinicians, and policy makers and eventually be tested in future clinical trials.

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We need to prioritize resources on strategies to prevent dementia.

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Treatment with B-vitamins at an early stage appears to be highly cost-effective.

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This provocative finding should be debated and tested.