Practical recommendations for timely, accurate diagnosis of symptomatic Alzheimer's disease (MCI and dementia) in primary care: a review and synthesis

Palliative Care in Early Dementia: A Scoping Review

BACKGROUND

Palliative care is recommended for all people with dementia from diagnosis through end-of-life. However, palliative care needs and effective elements of palliative care are not well-defined for the earlier stages of dementia.

OBJECTIVE

To systematically map current research on palliative care early in the disease trajectory of dementia.

DESIGN

Scoping review of scientific literature.

DATA SOURCES

PubMed, CINAHL, EMBASE, Cochrane, PsycINFO, Web of Science REVIEW METHODS: We included studies published in English over the last decade (through March 2022) that focused on palliative care in early stages of dementia and targeted outcomes in palliative care domains. Two authors independently screened abstracts and full texts and scored the quality of included studies using tools by the Joanna Briggs Institute.

RESULTS

Among the 77 papers reviewed, few addressed early stages of dementia specifically. We found that: 1) While "early" palliative care was not well-defined in the literature, evidence indicated that palliative care needs were present at or before diagnosis and across the trajectory. Notable opportunities for palliative care arise at 'tipping points' (i.e., when symptoms, functional status, or caregiving needs change). 2) Palliative care needs in early dementia include advocacy for goal-aligned care in the future, reassurance against the threat of negligence and abandonment by caregivers, planning for future scenarios of care (practical, individual, and relational needs), and establishing of long-term relationships with providers entrusted for care later in disease. 3) Elements of effective palliative care in early dementia could include dementia-specific ACP and goals of care discussions, navigation for building a network of support, provision of tools and resources for family, tailored care and knowledge of the person, and well-prepared dementia-care providers. The scarcity of palliative care studies aimed at early disease indicates a gap in the evidence in dementia care.

CONCLUSION

The literature on palliative care in early dementia is sparse. Future studies should focus on assessment tools for optimizing timing of palliative care in early dementia, gaining better understanding of patient and family needs during early phases of disease, and providing training for providers and families in long-term relationships and communication around goals of care and future planning.

Cognitive Impairment in the Primary Care Clinic

Cognitive impairment is a common problem in the geriatric population and is characterized by variable symptoms of memory difficulties, executive dysfunction, language or visuospatial problems, and behavioral changes. It is imperative that primary care clinicians recognize and differentiate the variable symptoms associated with cognitive impairment from changes attributable to normal aging or secondary to other medical conditions. A thorough evaluation for potentially reversible causes of dementia is required before diagnosis with a neurodegenerative dementia. Other abnormal neurologic findings, rapid progression, or early age of onset are red flags that merit referral to neurology for more specialized evaluation and treatment.

Heavy metal exposure and metabolomics analysis: an emerging frontier in environmental health

Exposure to heavy metals in various populations can lead to extensive damage to different organs, as these metals infiltrate and bioaccumulate in the human body, causing metabolic disruptions in various organs. To comprehensively understand the metal homeostasis, inter-organ "traffic," and extensive metabolic alterations resulting from heavy metal exposure, employing complementary analytical methods is crucial. Metabolomics is pivotal in unraveling the intricacies of disease vulnerability by furnishing thorough understandings of metabolic changes linked to different metabolic diseases. This field offers exciting prospects for enhancing the disease prevention, early detection, and tailoring treatment approaches to individual needs. This article consolidates the existing knowledge on disease-linked metabolic pathways affected by the exposure of diverse heavy metals providing concise overview of the underlying impact mechanisms. The main aim is to investigate the connection between the altered metabolic pathways and long-term complex health conditions induced by heavy metals such as diabetes mellitus, cardiovascular diseases, renal disorders, inflammation, neurodegenerative diseases, reproductive risks, and organ damage. Further exploration of common pathways may unveil the shared targets for treating associated pathological conditions. In this article, the role of metabolomics in disease susceptibility is emphasized that metabolomics is expected to be routinely utilized for the diagnosis and monitoring of diseases and practical value of biomarkers derived from metabolomics, as well as determining their appropriate integration into extensive clinical settings.

Intelligent prediction of Alzheimer's disease via improved multifeature squeeze-and-excitation-dilated residual network

This study aimed to address the issue of larger prediction errors existing in intelligent predictive tasks related to Alzheimer's disease (AD). A cohort of 487 enrolled participants was categorized into three groups: normal control (138 individuals), mild cognitive impairment (238 patients), and AD (111 patients) in this study. An improved multifeature squeeze-and-excitation-dilated residual network (MFSE-DRN) was proposed for two important AD predictions: clinical scores and conversion probability. The model was characterized as three modules: squeeze-and-excitation-dilated residual block (SE-DRB), multifusion pooling (MF-Pool), and multimodal feature fusion. To assess its performance, the proposed model was compared with two other novel models: ranking convolutional neural network (RCNN) and 3D vision geometrical group network (3D-VGGNet). Our method showed the best performance in the two AD predicted tasks. For the clinical scores prediction, the root-mean-square errors (RMSEs) and mean absolute errors (MAEs) of mini-mental state examination (MMSE) and AD assessment scale-cognitive 11-item (ADAS-11) were 1.97, 1.46 and 4.20, 3.19 within 6 months; 2.48, 1.69 and 4.81, 3.44 within 12 months; 2.67, 1.86 and 5.81, 3.83 within 24 months; 3.02, 2.03 and 5.09, 3.43 within 36 months, respectively. At the AD conversion probability prediction, the prediction accuracies within 12, 24, and 36 months reached to 88.0, 85.5, and 88.4%, respectively. The AD predication would play a great role in clinical applications.

2024 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease (AD), including prevalence and incidence, mortality and morbidity, use and costs of care and the ramifications of AD for family caregivers, the dementia workforce and society. The Special Report discusses the larger health care system for older adults with cognitive issues, focusing on the role of caregivers and non-physician health care professionals. An estimated 6.9 million Americans age 65 and older are living with Alzheimer's dementia today. This number could grow to 13.8 million by 2060, barring the development of medical breakthroughs to prevent or cure AD. Official AD death certificates recorded 119,399 deaths from AD in 2021. In 2020 and 2021, when COVID-19 entered the ranks of the top ten causes of death, Alzheimer's was the seventh-leading cause of death in the United States. Official counts for more recent years are still being compiled. Alzheimer's remains the fifth-leading cause of death among Americans age 65 and older. Between 2000 and 2021, deaths from stroke, heart disease and HIV decreased, whereas reported deaths from AD increased more than 140%. More than 11 million family members and other unpaid caregivers provided an estimated 18.4 billion hours of care to people with Alzheimer's or other dementias in 2023. These figures reflect a decline in the number of caregivers compared with a decade earlier, as well as an increase in the amount of care provided by each remaining caregiver. Unpaid dementia caregiving was valued at $346.6 billion in 2023. Its costs, however, extend to unpaid caregivers' increased risk for emotional distress and negative mental and physical health outcomes. Members of the paid health care and broader community-based workforce are involved in diagnosing, treating and caring for people with dementia. However, the United States faces growing shortages across different segments of the dementia care workforce due to a combination of factors, including the absolute increase in the number of people living with dementia. Therefore, targeted programs and care delivery models will be needed to attract, better train and effectively deploy health care and community-based workers to provide dementia care. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are almost three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 22 times as great. Total payments in 2024 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $360 billion. The Special Report investigates how caregivers of older adults with cognitive issues interact with the health care system and examines the role non-physician health care professionals play in facilitating clinical care and access to community-based services and supports. It includes surveys of caregivers and health care workers, focusing on their experiences, challenges, awareness and perceptions of dementia care navigation.

Memory complaint in a middle-income country: a four-year longitudinal study in a cohort with low-education

BACKGROUND

 Memory complaints are frequent in older adults and are associated with higher risk of cognitive decline.

OBJECTIVE

 To investigate the functional outcome of individuals with memory complaints followed up at primary care centers.

METHODS

 Data were collected between 2016 e 2020 in primary health care centers in Brazil. Patients underwent the Brief Cognitive Screening Battery, and the Functional Activities Questionnaire.

RESULTS

 The initial sample (2016) comprised 91 individuals classified into those with subjective cognitive decline (SCD, n = 15), mild cognitive impairment (MCI, n = 45), or dementia (n = 31). During follow-up, 8 individuals (8.8% of the initial sample) died and 26 (28.5% of the initial sample) were not found. Fifty-seven participants underwent clinical reassessment. Of 15 individuals with SCD, 7 were not found (46.7%), 4 (26.7%) progressed to MCI, and 4 (26.7%) remained stable. Of 45 individuals with MCI, 11 were not found (24.4%), 2 (4.4%) died, 6 (13.4%) progressed to dementia, 12 (26.7%) regressed to SCD, and 14 (31.1%) remained stable. Of 31 individuals with dementia, 8 were not found (25.8%), 6 (19.4%) died, 2 (6.5%) regressed to SCD, 7 (22.6%) regressed to MCI, and 8 remained stable (25.8%). Clinical improvement was due to the treatment of reversible causes, such as B12 hypovitaminosis and mood disorders. Older age, lower Mini-Mental State Examination, and higher scores of memory complaint, but not the use of benzodiazepines and of proton pump inhibitors, were predictors of functional status.

CONCLUSION

 Despite their limits (short sample size, missing data), these results support the idea that adequate screening, follow-up, and treatment of reversible causes of dementia in primary care are essential.

Neural Underpinnings of Learning in Dementia Populations: A Review of Motor Learning Studies Combined with Neuroimaging

The intent of this review article is to serve as an overview of current research regarding the neural characteristics of motor learning in Alzheimer disease (AD) as well as prodromal phases of AD: at-risk populations, and mild cognitive impairment. This review seeks to provide a cognitive framework to compare various motor tasks. We will highlight the neural characteristics related to cognitive domains that, through imaging, display functional or structural changes because of AD progression. In turn, this motivates the use of motor learning paradigms as possible screening techniques for AD and will build upon our current understanding of learning abilities in AD populations.

Adapting prescribing criteria for amyloid-targeted antibodies for adults with Down syndrome

Prior authorization criteria for Federal Drug Administration (FDA) approved immunotherapeutics, among the class of anti-amyloid monoclonal antibodies (mAbs), established by state drug formulary committees, are tailored for adults with late-onset Alzheimer's disease. This overlooks adults with Down syndrome (DS), who often experience dementia at a younger age and with different diagnostic assessment outcomes. This exclusion may deny DS adults access to potential disease-modifying treatments. To address this issue, an international expert panel convened to establish adaptations of prescribing criteria suitable for DS patients and parameters for access to Centers for Medicare & Medicaid Services (CMS) registries. The panel proposed mitigating disparities by modifying CMS and payer criteria to account for younger onset age, using alternative language and assessment instruments validated for cognitive decline in the DS population. The panel also recommended enhancing prescribing clinicians' diagnostic capabilities for DS and initiated awareness-raising activities within healthcare organizations. These efforts facilitated discussions with federal officials, aimed at achieving equity in access to anti-amyloid immunotherapeutics, with implications for national authorities worldwide evaluating these and other new disease-modifying therapeutics for Alzheimer's disease.

[Travel time to memory clinics in Bavaria: A geographical analyses within the framework of digiDEM Bayern]

BACKGROUND

Memory clinics can contribute significantly to a qualified diagnosis of dementia. Since the accessibility of medical facilities is an important predictor for their utilisation, the aim of this study was to determine the accessibility of memory clinics for persons with dementia in Bavaria.

METHODS

We used a Geographic Information System (GIS) to determine travel times to the nearest memory clinic for all Bavarian municipalities based on OpenStreetMap road network data.

RESULTS

The majority of the modelled persons with dementia in Bavaria (40%; n = 93,950) live in communities with an average travel time of 20 to 40 minutes to the nearest memory clinic. Almost 7,000 (3%) require more than one hour. Especially persons from rural communities have to travel significantly longer distances than people from urban areas.

CONCLUSION

In view of demographic developments, there is an urgent need for memory clinics to be accessible throughout the country for all persons with dementia, regardless of where they live. The systematic development of memory clinics in areas with long travel times or the establishment of mobile diagnostic services could help to improve dementia care.

People get ready! A new generation of Alzheimer's therapies may require new ways to deliver and pay for healthcare

The development of disease-modifying therapies (DMTs) for Alzheimer's disease (AD) has progressed over the last decade, and the first-ever therapies with potential to slow the progression of disease are approved in the United States. AD DMTs could provide life-changing opportunities for people living with this disease, as well as for their caregivers. They could also ease some of the immense societal and economic burden of dementia. However, AD DMTs also come with major challenges due to the large unmet medical need, high prevalence of AD, new costs related to diagnosis, treatment and monitoring, and uncertainty in the therapies' actual clinical value. This perspective article discusses, from the broad perspective of various health systems and stakeholders, how we can overcome these challenges and improve society's readiness for AD DMTs. We propose that innovative payment models such as performance-based payments, in combination with learning healthcare systems, could be the way forward to enable timely patient access to treatments, improve accuracy of cost-effectiveness evaluations and overcome budgetary barriers. Other important considerations include the need for identification of key drivers of patient value, the relevance of different economic perspectives (i.e. healthcare vs. societal) and ethical questions in terms of treatment eligibility criteria.

Prokaryote-derived phosphorylated Tau epitope vaccine is immunogenic and non-T-cell activated in the mice model

Accumulation of phosphorylated Tau protein is a prominent pathological hallmark of Alzheimer's disease (AD). However, current vaccines targeting phosphorylation sites are primarily modified using chemical reactions, which exhibit low efficiency in terms of linking to the vaccine carrier. Despite the identification of over 2000 phosphorylation sites on approximately 20% of E. coli proteins through proteomic studies, it remains unclear whether recombinant Tau proteins expressed in bacteria undergo direct phosphorylation. Additionally, limited information is available regarding the immunogenicity and safety profiles of prokaryotic-derived pTau epitope vaccines. Our study discovered that the prokaryotic system can induce phosphorylation on four residues (T181, T205, S262, and S396) of the full-length Tau protein. Based on this finding, we developed a prokaryotic-modified phosphorylated Tau protein vaccine and immunized wild-type mice, resulting in enhanced immunogenicity and a favorable safety profile.

Modelling the Distribution of Cognitive Outcomes for Early-Stage Neurocognitive Disorders: A Model Comparison Approach

Background: Cognitive assessments for patients with neurocognitive disorders are mostly measured by the Montreal Cognitive Assessment (MoCA) and Visual Cognitive Assessment Test (VCAT) as screening tools. These cognitive scores are usually left-skewed and the results of the association analysis might not be robust. This study aims to study the distribution of the cognitive outcomes and to discuss potential solutions. Materials and Methods: In this retrospective cohort study of individuals with subjective cognitive decline or mild cognitive impairment, the inverse-transformed cognitive outcomes are modelled using different statistical distributions. The robustness of the proposed models are checked under different scenarios: with intercept-only, models with covariates, and with and without bootstrapping. Results: The main results were based on the VCAT score and validated via the MoCA score. The findings suggested that the inverse transformation method improved the modelling the cognitive scores compared to the conventional methods using the original cognitive scores. The association of the baseline characteristics (age, gender, and years of education) and the cognitive outcomes were reported as estimates and 95% confidence intervals. Bootstrap methods improved the estimate precision and the bootstrapped standard errors of the estimates were more robust. Cognitive outcomes were widely analysed using linear regression models with the default normal distribution as a conventional method. We compared the results of our suggested models with the normal distribution under various scenarios. Goodness-of-fit measurements were compared between the proposed models and conventional methods. Conclusions: The findings support the use of the inverse transformation method to model the cognitive outcomes instead of the original cognitive scores for early-stage neurocognitive disorders where the cognitive outcomes are left-skewed.

Remote Self-Administration of Cognitive Screeners for Older Adults Prior to a Primary Care Visit: Pilot Cross-Sectional Study of the Reliability and Usability of the MyCog Mobile Screening App

BACKGROUND

Routine cognitive screening is essential in the early detection of dementia, but time constraints in primary care settings often limit clinicians' ability to conduct screenings. MyCog Mobile is a newly developed cognitive screening system that patients can self-administer on their smartphones before a primary care visit, which can help save clinics' time, encourage broader screening practices, and increase early detection of cognitive decline.

OBJECTIVE

The goal of this pilot study was to examine the feasibility, acceptability, and initial psychometric properties of MyCog Mobile. Research questions included (1) Can older adults complete MyCog Mobile remotely without staff support? (2) Are the internal consistency and test-retest reliability of the measures acceptable? and (3) How do participants rate the user experience of MyCog Mobile?

METHODS

A sample of adults aged 65 years and older (N=51) self-administered the MyCog Mobile measures remotely on their smartphones twice within a 2- to 3-week interval. The pilot version of MyCog Mobile includes 4 activities: MyFaces measures facial memory, MySorting measures executive functioning, MySequences measures working memory, and MyPictures measures episodic memory. After their first administration, participants also completed a modified version of the Simplified System Usability Scale (S-SUS) and 2 custom survey items.

RESULTS

All participants in the sample passed the practice items and completed each measure. Findings indicate that the Mobile Toolbox assessments measure the constructs well (internal consistency 0.73 to 0.91) and are stable over an approximately 2-week delay (test-retest reliability 0.61 to 0.71). Participants' rating of the user experience (mean S-SUS score 73.17, SD 19.27) indicated that older adults found the usability of MyCog Mobile to be above average. On free-response feedback items, most participants provided positive feedback or no feedback at all, but some indicated a need for clarity in certain task instructions, concerns about participants' abilities, desire to be able to contact a support person or use in-app technical support, and desire for additional practice items.

CONCLUSIONS

Pilot evidence suggests that the MyCog Mobile cognitive screener can be reliably self-administered by older adults on their smartphones. Participants in our study generally provided positive feedback about the MyCog Mobile experience and rated the usability of the app highly. Based on participant feedback, we will conduct further usability research to improve support functionality, optimize task instructions and practice opportunities, and ensure that patients feel comfortable using MyCog Mobile. The next steps include a clinical validation study that compares MyCog Mobile to gold-standard assessments and tests the sensitivity and specificity of the measures for identifying dementia.

Monoclonal antibodies for treating early Alzheimer disease-a commentary on recent 'positive' trials

Recent phase 3 randomised controlled trials of amyloid-targeting monoclonal antibodies in people with pre-clinical or early Alzheimer disease have reported positive results, raising hope of finally having disease-modifying drugs. Given their far-reaching implications for clinical practice, the methods and findings of these trials, and the disease causation theory underpinning the mechanism of drug action, need to be critically appraised. Key considerations are the representativeness of trial populations; balance of prognostic factors at baseline; psychometric properties and minimal clinically important differences of the primary efficacy outcome measures; level of study fidelity; consistency of subgroup analyses; replication of findings in similar trials; sponsor role and potential conflicts of interest; consistency of results with disease causation theory; cost and resource estimates; and alternative prevention and treatment strategies. In this commentary, we show shortcomings in each of these areas and conclude that monoclonal antibody treatment for early Alzheimer disease is lacking high-quality evidence of clinically meaningful impacts at an affordable cost.

Diagnostic accuracy of BASIC-Q for detection of cognitive impairment in a primary care setting - a cross-validation study

OBJECTIVES

This study aims to evaluate the diagnostic accuracy and reliability of a new, brief questionnaire, 'Brief Assessment of Impaired Cognition- Questionnaire' (BASIC-Q) for detection of cognitive impairment, primarily developed for use in primary care. BASIC-Q has three components: Self-report, Informant report, and Orientation. Self-report and Orientation are completed by the individual and Informant report is answered by a close relative.

METHODS

We included 275 participants ≥ 70 years, without a prior diagnosis of dementia, and with a close relative who agreed to participate as an informant. Participants were included prospectively in 14 general practices in urban and rural Denmark using a convenience sampling method. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the informant-completed Functional Activities Questionnaire (FAQ) and reported memory concern were used as a reference standard for the classification of the participants' cognitive function.

RESULTS

BASIC-Q demonstrated a fair to good diagnostic accuracy to differentiate between people with cognitive impairment and normal cognition with an area under the ROC curve (AUC) of 0.84 (95% CI 0.79-0.89) and a sensitivity and specificity of 0.80 (95% CI 0.72-0.87) and 0.71 (95% CI 0.63-0.78). A prorated BASIC-Q score derived from BASIC-Q without Informant report had significantly lower classification accuracy than the full BASIC-Q. The test-retest reliability of BASIC-Q was good with an intraclass correlation coefficient of 0.84.

CONCLUSION

BASIC-Q is a brief, easy-to-use questionnaire for identification of cognitive impairment in older adults. It demonstrated fair to good classification accuracy in a general practice setting and can be a useful case-finding tool when suspecting dementia in primary health care.

Combining Blood-Based Biomarkers and Structural MRI Measurements to Distinguish Persons with and without Significant Amyloid Plaques

Background

Amyloid-β (Aβ) plaques play a pivotal role in Alzheimer's disease. The current positron emission tomography (PET) is expensive and limited in availability. In contrast, blood-based biomarkers (BBBMs) show potential for characterizing Aβ plaques more affordably. We have previously proposed an MRI-based hippocampal morphometry measure to be an indicator of Aβ plaques.

Objective

To develop and validate an integrated model to predict brain amyloid PET positivity combining MRI feature and plasma Aβ42/40 ratio.

Methods

We extracted hippocampal multivariate morphometry statistics from MR images and together with plasma Aβ42/40 trained a random forest classifier to perform a binary classification of participant brain amyloid PET positivity. We evaluated the model performance using two distinct cohorts, one from the Alzheimer's Disease Neuroimaging Initiative (ADNI) and the other from the Banner Alzheimer's Institute (BAI), including prediction accuracy, precision, recall rate, F1 score, and AUC score.

Results

Results from ADNI (mean age 72.6, Aβ+ rate 49.5%) and BAI (mean age 66.2, Aβ+ rate 36.9%) datasets revealed the integrated multimodal (IMM) model's superior performance over unimodal models. The IMM model achieved prediction accuracies of 0.86 in ADNI and 0.92 in BAI, surpassing unimodal models based solely on structural MRI (0.81 and 0.87) or plasma Aβ42/40 (0.73 and 0.81) predictors.

CONCLUSIONS

Our IMM model, combining MRI and BBBM data, offers a highly accurate approach to predict brain amyloid PET positivity. This innovative multiplex biomarker strategy presents an accessible and cost-effective avenue for advancing Alzheimer's disease diagnostics, leveraging diverse pathologic features related to Aβ plaques and structural MRI.

Physical activity together for couples living with mild cognitive impairment (PAT-MCI): A feasibility study

Mild cognitive impairment is a prodromal phase of Alzheimer's disease and related dementias. Cognitive and/or neuropsychiatric symptoms that could worsen over time cause challenges for patients and romantic partners, who often assume the role of informal caregivers. Although physical activity is beneficial, older adults with mild cognitive impairment and their romantic care partners are generally physically inactive. Our 16-week study was performed to see whether physical activity together is feasible to increase physical activity among four dyads (individuals with mild cognitive impairment and their spouses). Our dyadic intervention was feasible given more than 70 % of participants self-reported adherence to physical activity based on the guidelines for adults in the United States. In exit interviews, togetherness was highlighted as one of the biggest strengths of this study. Future studies with more representative samples are needed, as well as adopting a more tailored approach that accounts for individuals' levels of physical fitness.

Cognitive Screening for Mild Cognitive Impairment: Clinician Perspectives on Current Practices and Future Directions

 This study surveyed 51 specialist clinicians for their views on existing cognitive screening tests for mild cognitive impairment and their opinions about a hypothetical remote screener driven by artificial intelligence (AI). Responses revealed significant concerns regarding the sensitivity, specificity, and time taken to administer current tests, along with a general willingness to consider adopting telephone-based screening driven by AI. Findings highlight the need to design screeners that address the challenges of recognizing the earliest stages of cognitive decline and that prioritize not only accuracy but also stakeholder input.

Dementia and comorbidities in primary care: a scoping review

BACKGROUND

People with dementia (PwD) are known to have more chronic conditions compared to those without dementia, which can impact the clinical presentation of dementia, complicate clinical management and reduce overall quality of life. While primary care providers (PCPs) are integral to dementia care, it is currently unclear how PCPs adapt dementia care practices to account for comorbidities. This scoping review maps recent literature that describes the role for PCPs in the prevention, detection/diagnosis and management of dementia in the context of comorbidities, identifies critical knowledge gaps and proposes potential avenues for future research.

METHODS

We searched for peer-reviewed literature published between 2017-2022 in MEDLINE, Cochrane Library, and Scopus using key terms related to dementia, primary care, and comorbidity. The literature was screened for relevance by title-abstract screening and subsequent full-text screening. The prioritized papers were categorized as either 'Risk Assessment and Prevention', 'Screening, Detection, and Diagnosis' or 'Management' and were further labelled as either 'Tools and Technologies', 'Recommendations for Clinical Practice' or 'Programs and Initiatives'.

RESULTS

We identified 1,058 unique records in our search and respectively excluded 800 and 230 publications during title-abstract and full-text screening. Twenty-eight articles were included in our review, where ~ 50% describe the development and testing of tools and technologies that use pre-existing conditions to assess dementia risk. Only one publication provides official dementia screening guidelines for PCPs in people with pre-existing conditions. About 30% of the articles discuss managing the care of PwD, where most were anchored around models of multidisciplinary care and mitigating potentially inappropriate prescribing.

CONCLUSION

To our knowledge, this is the first scoping review that examines the role for PCPs in the prevention, detection/diagnosis and management of dementia in the context of comorbidities. Given our findings, we recommend that future studies: 1) further validate tools for risk assessment, timely detection and diagnosis that incorporate other health conditions; 2) provide additional guidance into how comorbidities could impact dementia care (including prescribing medication) in primary care settings; 3) incorporate comorbidities into primary care quality indicators for dementia; and 4) explore how to best incorporate dementia and comorbidities into models/frameworks of holistic, person-centred care.

Voxel-wise Fusion of Resting fMRI Networks and Gray Matter Volume for Alzheimer's Disease Classification using Deep Multimodal Learning

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder requiring accurate and early diagnosis for effective treatment. Resting-state functional magnetic resonance imaging (rs-fMRI) and gray matter volume analysis from structural MRI have emerged as valuable tools for investigating AD-related brain alterations. However, the potential benefits of integrating these modalities using deep learning techniques remain unexplored. In this study, we propose a novel framework that fuses composite images of multiple rs-fMRI networks (called voxelwise intensity projection) and gray matter segmentation images through a deep learning approach for improved AD classification. We demonstrate the superiority of fMRI networks over commonly used metrics such as amplitude of low-frequency fluctuations (ALFF) and fractional ALFF in capturing spatial maps critical for AD classification. We use a multi-channel convolutional neural network incorporating the AlexNet dropout architecture to effectively model spatial and temporal dependencies in the integrated data. Extensive experiments on the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset of AD patients and cognitively normal (CN) validate the efficacy of our approach, showcasing improved classification performance of 94.12% test accuracy and an area under the curve (AUC) score of 97.79 compared to existing methods. Our results show that the fusion results generally outperformed the unimodal results. The saliency visualizations also show significant differences in the hippocampus, amygdala, putamen, caudate nucleus, and regions of basal ganglia which are in line with the previous neurobiological literature. Our research offers a novel method to enhance our grasp of AD pathology. By integrating data from various functional networks with structural MRI insights, we significantly improve diagnostic accuracy. This accuracy is further boosted by the effective visualization of this combined information. This lays the groundwork for further studies focused on providing a more accurate and personalized approach to AD diagnosis. The proposed framework and insights gained from fMRI networks provide a promising avenue for future research in deep multimodal fusion and neuroimaging analysis.

Effects of Neighboring Phosphorylation Events on the Affinities of pT181-Tau Antibodies

A tau variant phosphorylated on threonine 181 (pT181-tau) has been widely investigated as a potential Alzheimer's disease (AD) biomarker in cerebrospinal fluid (CSF) and blood. pT181-tau is present in neurofibrillary tangles (NFTs) of AD brains, and CSF levels of pT181-tau correlate with the overall NFT burden. Various immunobased analytical methods, including Western blotting and ELISA, have been used to quantify pT181-tau in human biofluids. The reliability of these methods is dependent on the affinity and binding specificity of the antibodies used to measure pT181-tau levels. Although both of these properties could, in principle, be affected by phosphorylation within or near the antibody's cognate antigen, such effects have not been extensively studied. Here, we developed a biolayer interferometry assay to determine the degree to which the affinity of pT181-tau antibodies is altered by the phosphorylation of serine or threonine residues near the target epitope. Our results revealed that phosphorylation near T181 negatively affected the binding of pT181-tau antibodies to their cognate antigen to varying degrees. In particular, two of three antibodies tested showed a complete loss of affinity for the pT181 target when S184 or S185 was phosphorylated. These findings highlight the importance of selecting antibodies that have been thoroughly characterized in terms of affinity and binding specificity, addressing the potential disruptive effects of post-translational modifications in the epitope region to ensure accurate biomarker quantitation.

Gait and/or balance disturbances associated with Alzheimer's dementia among older adults with amnestic mild cognitive impairment: A longitudinal observational study

AIMS

To explore whether gait and/or balance disturbances are associated with the onset of Alzheimer's dementia (AD) among older adults with amnestic mild cognitive impairment (MCI).

DESIGN

This study employed a longitudinal retrospective cohort design.

METHODS

We obtained data from the National Alzheimer's Coordinating Center's Uniform Data Set collected from 35 National Institute on Aging Alzheimer's Disease Research Centers between September 2005 and December 2021. The mean age of participants (n = 2692) was 74.5 years with women making up 47.2% of the sample. Risk of incident AD according to baseline gait and/or balance disturbances as measured using the Postural Instability and Gait Disturbance Score, a subscale of the Unified Parkinson's Disease Rating Scale Motor Score, was examined by the Cox proportional hazards regression models adjusting for baseline demographics, medical conditions and study sites. The mean follow-up duration was 4.0 years.

RESULTS

Among all the participants, the presence or the severity of gait and/or balance disturbances was associated with an increased risk of AD. The presence or the severity of gait and/or balance disturbances was associated with a higher risk of Alzheimer's dementia among the subgroups of female and male participants.

CONCLUSION

Gait and/or balance disturbances may increase the risk of developing AD, regardless of sex.

IMPACT

Gait and/or balance disturbances among community-dwelling older adults with amnestic MCI may need to be frequently assessed by nurses to identify potential risk factors for cognitive decline.

NO PATIENT OR PUBLIC CONTRIBUTION

Given the secondary analysis, patients, service users, caregivers or members of the public were not directly involved in this study.

Alzheimer Disease: A Life-Limiting Disease With a Burden of a Terminal Illness

Purpose of Review

An estimated 6.5 million Americans live with Alzheimer dementia. Better understanding of advanced stages of Alzheimer disease (AD) and timely monitoring of its preventable complications would translate to improved survival and quality of life in this population.

Recent Findings

In this perspective review, we proposed shifting the narrative to recognizing AD as a chronic life-limiting illness instead of a terminal disease. In support of this view, we discussed the following: (1) the biochemical, cellular (preclinical), and clinical phases of AD; (2) survival after AD; (3) AD therapeutics and potential implications for the population with AD in the advanced stages.

Summary

On the bases of the prolonged preclinical phase in AD, promising advances in AD therapeutics and the varying survival after AD, we proposed a new classification for AD and more broadly neurodegenerative disorders to be recognized as chronic life-limiting illnesses rather than terminal diseases with important implications for patients with AD in the advanced stages given the challenges that are specific to this population.

Understanding barriers to and facilitators of clinician-patient conversations about brain health and cognitive concerns in primary care: a systematic review and practical considerations for the clinician

BACKGROUND

Primary care clinicians (PCCs) are typically the first practitioners to detect cognitive impairment in their patients, including those with Alzheimer's disease or related dementias (ADRD). However, conversations around cognitive changes can be challenging for patients, family members, and clinicians to initiate, with all groups reporting barriers to open dialogue. With the expanding array of evidence-based interventions for ADRD, from multidomain care management to novel biotherapeutics for early-stage AD, incorporating conversations about brain health into routine healthcare should become a standard of care. We conducted a systematic review to identify barriers to and facilitators of brain health conversations in primary care settings.

METHODS

We systematically searched PubMed, Scopus, Web of Science, and the Cochrane Library for qualitative or quantitative studies conducted in the US between January 2000 and October 2022 that evaluated perceptions of cognition and provider-patient brain health conversations prior to formal screening for, or diagnosis of, mild cognitive impairment or ADRD. We assessed the quality of the included studies using the Mixed Methods Appraisal Tool.

RESULTS

In total, 5547 unique abstracts were screened and 22 articles describing 19 studies were included. The studies explored perceptions of cognition among laypersons or clinicians, or provider-patient interactions in the context of a patient's cognitive concerns. We identified 4 main themes: (1) PCCs are hesitant to discuss brain health and cognitive concerns; (2) patients are hesitant to raise cognitive concerns; (3) evidence to guide clinicians in developing treatment plans that address cognitive decline is often poorly communicated; and (4) social and cultural context influence perceptions of brain health and cognition, and therefore affect clinical engagement.

CONCLUSIONS

Early conversations about brain health between PCCs and their patients are rare, and effective tools, processes, and strategies are needed to make these vital conversations routine.

Cholinesterase inhibitors and falls, syncope and injuries in patients with cognitive impairment: a systematic review and meta-analysis

BACKGROUND

Cholinesterase inhibitors are commonly used to treat patients with neurocognitive disorders, who often have an elevated risk of falling. Effective use of these medications requires a thoughtful assessment of risks and benefits.

OBJECTIVE

To provide an update on previous reviews and determine the association between cholinesterase inhibitors and falls, syncope, fracture and accidental injuries in patients with neurocognitive disorders.

METHODS

Embase, MEDLINE, Cochrane Central Register of Controlled Trials, Cumulative Index of Nursing and Allied Health Literature and AgeLine were systematically searched through March 2023 to identify all randomised controlled trials of cholinesterase inhibitors (donepezil, galantamine, rivastigmine) in patients with cognitive impairment. Corresponding authors were contacted for additional data necessary for meta-analysis. Inclusion criteria consisted of adults ≥19 years, with a diagnosis of dementia, Parkinson's disease, mild cognitive impairment or traumatic brain injury. Data were extracted in duplicate for the aforementioned primary outcomes and all outcomes were analysed using random-effects meta-analysis.

RESULTS

Fifty three studies (30 donepezil, 14 galantamine, 9 rivastigmine) were included providing data on 25, 399 patients. Cholinesterase inhibitors, compared to placebo, were associated with reduced risk of falls (risk ratio [RR] 0.84 [95% confidence interval [CI] = 0.73-0.96, P = 0.009]) and increased risk of syncope (RR 1.50 [95% CI = 1.02-2.21, P = 0.04]). There was no association with accidental injuries or fractures.

CONCLUSION

In patients with neurocognitive disorders, cholinesterase inhibitors were associated with decreased risk of falls, increased risk of syncope and no association with accidental trauma or fractures. These findings will help clinicians better evaluate risks and benefits of cholinesterase inhibitors.

Using a dual-stream attention neural network to characterize mild cognitive impairment based on retinal images

Mild cognitive impairment (MCI) is a critical transitional stage between normal cognition and dementia, for which early detection is crucial for timely intervention. Retinal imaging has been shown as a promising potential biomarker for MCI. This study aimed to develop a dual-stream attention neural network to classify individuals with MCI based on multi-modal retinal images. Our approach incorporated a cross-modality fusion technique, a variable scale dense residual model, and a multi-classifier mechanism within the dual-stream network. The model utilized a residual module to extract image features and employed a multi-level feature aggregation method to capture complex context information. Self-attention and cross-attention modules were utilized at each convolutional layer to fuse features from optical coherence tomography (OCT) and fundus modalities, resulting in multiple output losses. The neural network was applied to classify individuals with MCI, Alzheimer's disease, and control participants with normal cognition. Through fine-tuning the pre-trained model, we classified community-dwelling participants into two groups based on cognitive impairment test scores. To identify retinal imaging biomarkers associated with accurate prediction, we used the Gradient-weighted Class Activation Mapping technique. The proposed method achieved high precision rates of 84.96% and 80.90% in classifying MCI and positive test scores for cognitive impairment, respectively. Notably, changes in the optic nerve head on fundus photographs or OCT images among patients with MCI were not used to discriminate patients from the control group. These findings demonstrate the potential of our approach in identifying individuals with MCI and emphasize the significance of retinal imaging for early detection of cognitive impairment.

Understanding the role of psychiatrists in the diagnosis and management of mild cognitive impairment and mild Alzheimer's disease dementia: a cross-sectional survey

BACKGROUND

Alzheimer's disease (AD) is a progressive neurological disorder and the most common cause of dementia. The clinical continuum of AD ranges from asymptomatic disease to mild cognitive impairment (MCI), followed by AD dementia, categorized as mild, moderate, or severe. Almost one-third of patients suspected of having MCI or mild AD dementia are referred to specialists including psychiatrists. We sought to better understand the role that psychiatrists play in the diagnosis, treatment, and management of patients with all-cause MCI or mild AD dementia.

METHODS

We conducted an anonymous, online survey among physicians in the United States between February 4, 2021, and March 1, 2021. We surveyed psychiatrists, primary care physicians (PCPs), geriatricians, and neurologists who treat patients with all-cause MCI or mild AD dementia.

RESULTS

A total of 301 physicians participated in the survey, 50 of whom were psychiatrists. Of their patients with all-cause MCI or mild AD dementia, psychiatrists reported personally diagnosing two-thirds (67%). Psychiatrists used various methods to diagnose MCI or mild AD dementia including mental status testing (94%), review of patient medical history (86%), and neurological exams (61%). Upon diagnosis, psychiatrists reported most commonly discussing treatments (86%), management strategies (80%), disease progression (72%), and etiology of MCI or mild AD dementia (72%) with their patients. Most psychiatrists surveyed (82%) reported receiving advanced formal training in MCI and AD dementia care, primarily via residency training (38%), continuing medical education (22%) or fellowship (18%). Additionally, almost all psychiatrists (92%) reported receiving referrals for ongoing management of patients with MCI or mild AD dementia, primarily from PCPs or neurologists. However, only 46% of psychiatrists viewed themselves as the coordinator of care for their patients with MCI or mild AD dementia.

CONCLUSIONS

Many psychiatrists indicated that they were well-informed about MCI and AD dementia and have a strong interest in providing care for these patients. They can provide timely and accurate diagnosis of clinical MCI and mild AD dementia and develop optimal treatment plans for patients. Although many psychiatrists consider other physicians to be the care coordinators for patients with MCI and mild AD dementia, psychiatrists can play a key role in diagnosing and managing patients with MCI and mild AD dementia.

Cognitive status and its risk factors in patients with hypertension and diabetes in a low-income rural area of China: A cross-sectional study

OBJECTIVES

The proportion of older people with dementia in China is gradually increasing with the increase in the aging population over recent years. Hypertension and diabetes are common non-communicable diseases among rural populations in China. However, it remains unclear whether these conditions affect the occurrence and development of cognitive impairment as there is limited research on cognitive status and its risk factors among residents of rural areas.

METHODS

A multi-stage stratified cluster random sampling method was used to select 5400 participants from rural permanent residents. A self-designed structured questionnaire was used to investigate demographic data of the participants. Cognitive function was assessed using the Montreal Cognitive Function Assessment Scale (MoCA). The results were analyzed using chi-square test, ANOVA and multiple linear regression analysis.

RESULTS

A total of 5028 participants returned the survey, giving a response rate of 93.1%. Higher education (odds ratio (OR) = 3.2, 95% confidence interval (CI) 2.87-3.54, p < 0.001), higher income (OR = 1.61, 95% CI 1.16-2.07, p < 0.001), and dietary control (OR = 0.66, 95%CI 0.34-0.98, p < 0.001) were protective factors. A visual representation of the relationship between annual income and MoCA score showed an inverted U-curve, the group with an annual income of 6000-7999 RMB had a maximum OR of 1.93 (95%CI 0.12-2.74, p < 0.001). While difficulty in maintaining sleep were risk factors for cognitive impairment (OR = -2.28, 95% CI-4.18-0.39, p = 0.018).

CONCLUSIONS

Participants with middle incomes had better cognitive status than those with the highest incomes. Higher education, proper diet control and good sleep are beneficial to the cognitive status of residents in rural areas.

[Mild cognitive impairment in geriatric practice: patient orientation, diagnostics, treatment and ethics]

Mild cognitive impairment (MCI) is a common problem in old people, which can be distressing for patients and their families. The main feature of MCI is a decrease in cognitive performance with activities of daily living still unimpaired. The identification of treatable risk factors, recognition of early cognitive changes and a timely differential diagnosis, comprehensive information and counselling are important tasks in geriatric medicine. The aim of this article is to present practical recommendations to support physicians working with geriatric patients in recognizing cognitive deficits at an early stage, provide high-quality care focusing on counselling, treatment, and comorbidity management and to maximize the potential of the available treatment options.

Altered Extracellular Vesicle miRNA Profile in Prodromal Alzheimer's Disease

Extracellular vesicles (EVs) are nanosized vesicles released by almost all body tissues, representing important mediators of cellular communication, and are thus promising candidate biomarkers for neurodegenerative diseases like Alzheimer's disease (AD). The aim of the present study was to isolate total EVs from plasma and characterize their microRNA (miRNA) contents in AD patients. We isolated total EVs from the plasma of all recruited subjects using ExoQuickULTRA exosome precipitation solution (SBI). Subsequently, circulating total EVs were characterized using Nanosight nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and Western blotting. A panel of 754 miRNAs was determined with RT-qPCR using TaqMan OpenArray technology in a QuantStudio 12K System (Thermo Fisher Scientific). The results demonstrated that plasma EVs showed widespread deregulation of specific miRNAs (miR-106a-5p, miR-16-5p, miR-17-5p, miR-195-5p, miR-19b-3p, miR-20a-5p, miR-223-3p, miR-25-3p, miR-296-5p, miR-30b-5p, miR-532-3p, miR-92a-3p, and miR-451a), some of which were already known to be associated with neurological pathologies. A further validation analysis also confirmed a significant upregulation of miR-16-5p, miR-25-3p, miR-92a-3p, and miR-451a in prodromal AD patients, suggesting these dysregulated miRNAs are involved in the early progression of AD.

Six-item cognitive impairment test (6-CIT)'s accuracy as a cognitive screening tool: best cut-off levels in emergency department setting

Background

Nowadays, elderly patients represent a significant number of accesses to the Emergency Department (ED). Working rhythms do not allow to perform complete cognitive analysis, which would, however, be useful for the health care. This study aims to define the optimal cut-off values of the six-item Cognitive Impairment Test (6-CIT) as a cognitive screening tool in ED.

Methods

This study included 215 subjects, evaluated at the Emergency Department of the University Hospital of Monserrato, Cagliari, Italy, from July to December 2021. The accuracy of 6-CIT as a cognitive screening tool was assessed by comparison with Mini Mental State Examination (MMSE).

Results

The correlation coefficient between the two tests was -0.836 (CI: -0.87 to -0.79; p < 0.0001), and 6-CIT showed AUC = 0.947 (CI: 0.908-0.973; p < 0.0001). The 8/9 6-CIT cut-off score presented 86.76% sensitivity (CI: 76.4-93.8) and 91.84% specificity (CI: 86.2-95.7), and Youden index for this score was 0.786.

Conclusion

Our study demonstrates that 6-CIT is a reliable cognitive screening tool in ED, offering excellent sensitivity and specificity with a 8/9 points cut-off score.

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.

Cognitive assessment in primary care: Practical recommendations

ABSTRACT

Primary care clinicians play a critical role in both the identification and management of cognitive impairment due to common diseases. Primary care practices should incorporate feasible, reliable, and helpful tools into existing workflow to recognize and support people living with dementia and their care partners.

Differential relationships of NMDAR hypofunction and oxidative stress with cognitive decline

NMDAR hypofunction and oxidative stress are implicated in the pathogenesis of Alzheimer's disease. D-amino acid oxidase (DAO) regulates NMDAR function. Glutathione, superoxide dismutase, and catalase are three first-line endogenous antioxidants. This study explored the associations of these potential biomarkers with mild cognitive impairment. Cognitive function and blood levels of DAO, glutathione, superoxide dismutase, and catalase were measured in 63 mild cognitive impairment patients and 24 healthy individuals every 6 months for 2 years. Among the patients, DAO and glutathione levels at baseline contributed to the cognitive decline 2 years later. Among the healthy individuals, only glutathione levels were associated with cognitive change. The four biomarkers differed in change directions (upward vs. downward) in the patients and in the healthy individuals. Among patients, glutathione levels were negatively correlated with superoxide dismutase and positively correlated with catalase, and DAO levels were negatively correlated with superoxide dismutase. To our knowledge, this is the first study to demonstrate the differential associations of NMDAR hypofunction and oxidative stress with cognitive change between the mild cognitive impairment patients and healthy people. Glutathione may be regarded as an aging marker for both mild cognitive impairment and normal aging; and DAO, a biomarker exclusively for mild cognitive impairment.

Undiagnosed Cognitive Impairment and Impact on Instrumental Activities of Daily Living Among People With HIV Infection in Primary Care

Background

Little is known about the prevalence of undiagnosed cognitive impairment and its impact on instrumental activities of daily living (IADL) among people with HIV (PWH) in primary care.

Methods

PWH were recruited from an integrated health care setting in the United States. PWH were eligible for recruitment if they were ≥50 years old, taking antiretroviral therapy (ie, ≥1 antiretroviral therapy [ART] prescription fill in the past year), and had no clinical diagnosis of dementia. Participants completed a cognitive screen (St. Louis University Mental Status exam) and a questionnaire on IADL (modified Lawton-Brody).

Results

Study participants (n = 47) were mostly male (85.1%), 51.1% White, 25.5% Black, 17.0% Hispanic, and the average age (SD) was 59.7 (7.0) years. Overall, 27 (57.5%) participants were categorized as cognitively normal, 17 (36.2%) as having mild cognitive impairment, and 3 (6.4%) as having possible dementia. Of the 20 participants with mild cognitive impairment or possible dementia, 85.0% were men, the average age (SD) was 60.4 (7.1) years; 45.0% were White, 40.0% were Black, 10.0% were Hispanic, and 30.0% reported difficulty with at least 1 IADL. Most (66.7%) attributed difficulty with IADL primarily (33.3%) or in part (33.3%) to cognitive problems.

Conclusions

Undiagnosed cognitive impairment is frequent among ART-treated PWH, with possible elevated risk among Black PWH, and may be accompanied by difficulty with IADL. Efforts are needed to optimize identification of factors contributing to cognitive and IADL difficulties among ART-treated PWH in primary care.

Retinal imaging biomarkers of Alzheimer's disease: A systematic review and meta-analysis of studies using brain amyloid beta status for case definition

Introduction

We performed a systematic review and meta-analysis of the association between retinal imaging parameters and Alzheimer's disease (AD).

Methods

PubMed, EMBASE, and Scopus were systematically searched for prospective and observational studies. Included studies had AD case definition based on brain amyloid beta (Aβ) status. Study quality assessment was performed. Random-effects meta-analyses of standardized mean difference, correlation, and diagnostic accuracy were conducted.

Results

Thirty-eight studies were included. There was weak evidence of peripapillary retinal nerve fiber layer thinning on optical coherence tomography (OCT) (p = 0.14, 11 studies, n = 828), increased foveal avascular zone area on OCT-angiography (p = 0.18, four studies, n = 207), and reduced arteriole and venule vessel fractal dimension on fundus photography (p < 0.001 and p = 0.08, respectively, three studies, n = 297) among AD cases.

Discussion

Retinal imaging parameters appear to be associated with AD. Small study sizes and heterogeneity in imaging methods and reporting make it difficult to determine utility of these changes as AD biomarkers.

Highlights

We performed a systematic review on retinal imaging and Alzheimer's disease (AD).We only included studies in which cases were based on brain amyloid beta status.Several retinal biomarkers were associated with AD but clinical utility is uncertain.Studies should focus on biomarker-defined AD and use standardized imaging methods.

Cognition and cardiovascular comorbidities among older adults in primary care in West India

Objectives

Cardiovascular risk factors (e.g., diabetes and hypertension) are comorbidities associated with cognitive impairment. The present study was planned to study the relationship between cardiovascular risk factors and cognitive impairment using General Practitioner assessment of Cognition (GPCOG) scale, which is easy to use scale in the primary care.

Materials and Methods

A total of 350 older adults (mean age=66.71 ± 6.53 years; M:F = 220:130) among 3000 who reported to the primary care center in West India were screened. Cardiovascular risk factors were assessed based on written medical records. GPCOG was used for cognitive screening of those over the age of 60 with subjective memory complaints.

Results

Frequency of cardiovascular (CV) risk factors in those with cognitive impairment was 46.2% (n = 162/350) and 29% (101/350) in those without cognitive impairment. A Chi-square test of proportion showed values to be statistically significantly different (Chi-square value = 22.04; P =< 0.001; 95% confidence interval [CI] = 10.0463-24.1076%). Odds ratio was found to be 1.6 (95% CI =2-2.1; P =< 0.05).

Conclusion

A higher CV risk factors were observed among those with cognitive impairment compared to those cognitively normal older adults in the primary care.

2023 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease, including prevalence and incidence, mortality and morbidity, use and costs of care, and the overall impact on family caregivers, the dementia workforce and society. The Special Report examines the patient journey from awareness of cognitive changes to potential treatment with drugs that change the underlying biology of Alzheimer's. An estimated 6.7 million Americans age 65 and older are living with Alzheimer's dementia today. This number could grow to 13.8 million by 2060 barring the development of medical breakthroughs to prevent, slow or cure AD. Official death certificates recorded 121,499 deaths from AD in 2019, and Alzheimer's disease was officially listed as the sixth-leading cause of death in the United States. In 2020 and 2021, when COVID-19 entered the ranks of the top ten causes of death, Alzheimer's was the seventh-leading cause of death. Alzheimer's remains the fifth-leading cause of death among Americans age 65 and older. Between 2000 and 2019, deaths from stroke, heart disease and HIV decreased, whereas reported deaths from AD increased more than 145%. This trajectory of deaths from AD was likely exacerbated by the COVID-19 pandemic in 2020 and 2021. More than 11 million family members and other unpaid caregivers provided an estimated 18 billion hours of care to people with Alzheimer's or other dementias in 2022. These figures reflect a decline in the number of caregivers compared with a decade earlier, as well as an increase in the amount of care provided by each remaining caregiver. Unpaid dementia caregiving was valued at $339.5 billion in 2022. Its costs, however, extend to family caregivers' increased risk for emotional distress and negative mental and physical health outcomes - costs that have been aggravated by COVID-19. Members of the paid health care workforce are involved in diagnosing, treating and caring for people with dementia. In recent years, however, a shortage of such workers has developed in the United States. This shortage - brought about, in part, by COVID-19 - has occurred at a time when more members of the dementia care workforce are needed. Therefore, programs will be needed to attract workers and better train health care teams. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are almost three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 22 times as great. Total payments in 2023 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $345 billion. The Special Report examines whether there will be sufficient numbers of physician specialists to provide Alzheimer's care and treatment now that two drugs are available that change the underlying biology of Alzheimer's disease.

The common marmoset as a model of neurodegeneration

Human life expectancy has increased over the past few centuries, and the incidence of dementia in the older population is also projected to continue to rise. Neurodegenerative diseases are complex multifactorial conditions for which no effective treatments are currently available. Animal models are necessary to understand the causes and progression of neurodegeneration. Nonhuman primates (NHPs) offer significant advantages for the study of neurodegenerative disease. Among them, the common marmoset, Callithrix jacchus, stands out due to its easy handling, complex brain architecture, and occurrence of spontaneous beta-amyloid (Aβ) and phosphorylated tau aggregates with aging. Furthermore, marmosets present physiological adaptations and metabolic alterations associated with the increased risk of dementia in humans. In this review, we discuss the current literature on the use of marmosets as a model of aging and neurodegeneration. We highlight aspects of marmoset physiology associated with aging, such as metabolic alterations, which may help understand their vulnerability to developing a neurodegenerative phenotype that goes beyond normal aging.

Association of Subjective Cognitive Decline With Progression to Dementia in a Cognitively Unimpaired Multiracial Community Sample

BACKGROUND AND OBJECTIVES

This prospective study seeks to examine the utility of subjective cognitive decline (SCD) as a marker of future progression to dementia in a community-based cohort of non-Latinx White, non-Latinx Black, and Latinx individuals. Debate surrounds the utility of SCD, the subjective perception of decline in one's cognition before such impairment is evident in traditional neuropsychological assessments, as an early indicator of impending Alzheimer disease. Unfortunately, most studies examining SCD have been conducted in non-Latinx White samples and commonly exclude groups of individuals shown to be most vulnerable to dementia.

METHODS

Participants were enrolled into this cohort study from the Washington Heights-Inwood Columbia Aging Project if they were cognitively unimpaired, had baseline measurement of SCD, and self-identified as non-Latinx White, non-Latinx Black, or Latinx. SCD was measured as a continuous sum of 10 items assessing cognitive complaints. Competing risk models tested the main effects of baseline SCD on progression to dementia. Models were adjusted for age, sex/gender, years of education, medical comorbidity burden, enrollment cohort, and baseline memory test performance with death jointly modelled as a function of race/ethnicity.

RESULTS

A total of 4,043 (1,063 non-Latinx White, 1,267 non-Latinx Black, and 1,713 Latinx) participants were selected for this study with a mean age of 75 years, 67% women, and with a mean follow-up of 5 years. Higher baseline SCD was associated with increased rates of incident dementia over time in the full sample (hazard ratio [HR] 1.085, CI 1.047-1.125, p < 0.001) and within Latinx (HR 1.084, CI 1.039-1.130, p < 0.001) and non-Latinx Black individuals (HR 1.099, CI 1.012-1.194, p = 0.024).

DISCUSSION

Overall results of this study support SCD as a prodromal marker of dementia in a multiracial community sample, and in Latinx and non-Latinx Black individuals in particular. Because models examining the risk of dementia were adjusted for baseline memory test performance, the results support the idea that SCD, a subjective reflection of one's own current cognitive functioning, contributes information above and beyond standard memory testing. Current findings highlight the importance of carefully evaluating any memory concerns raised by older adults during routine visits and underscore the potential utility of screening older adults for SCD.

MicroRNAs and MAPKs: Evidence of These Molecular Interactions in Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder known to be the leading cause of dementia worldwide. Many microRNAs (miRNAs) were found deregulated in the brain or blood of AD patients, suggesting a possible key role in different stages of neurodegeneration. In particular, mitogen-activated protein kinases (MAPK) signaling can be impaired by miRNA dysregulation during AD. Indeed, the aberrant MAPK pathway may facilitate the development of amyloid-beta (Aβ) and Tau pathology, oxidative stress, neuroinflammation, and brain cell death. The aim of this review was to describe the molecular interactions between miRNAs and MAPKs during AD pathogenesis by selecting evidence from experimental AD models. Publications ranging from 2010 to 2023 were considered, based on PubMed and Web of Science databases. According to obtained data, several miRNA deregulations may regulate MAPK signaling in different stages of AD and conversely. Moreover, overexpressing or silencing miRNAs involved in MAPK regulation was seen to improve cognitive deficits in AD animal models. In particular, miR-132 is of particular interest due to its neuroprotective functions by inhibiting Aβ and Tau depositions, as well as oxidative stress, through ERK/MAPK1 signaling modulation. However, further investigations are required to confirm and implement these promising results.

Cleveland Clinic Cognitive Battery (C3B): Normative, Reliability, and Validation Studies of a Self-Administered Computerized Tool for Screening Cognitive Dysfunction in Primary Care

BACKGROUND

The self-administered iPad-based Cleveland Clinic Cognitive Battery (C3B) was designed specifically for the efficient screening of cognitive functioning of older adults in a primary care setting.

OBJECTIVE

1) Generate regression-based norms from healthy participants to enable demographic corrections to facilitate clinical interpretation; 2) estimate test-retest reliability and practice effects; 3) examine ability to discriminate mild cognitive impairment (MCI) from healthy aging; 4) d etermine validity of screening in a distracting clinical environment; and 5) determine completion rates and patient satisfaction in a primary care setting.

METHODS

Study 1 (S1) recruited a stratified sample of 428 healthy adults, ages 18-89, to generate regression-based equations. S2 assessed 2-week test-retest reliability and practice effects in 30 healthy elders. S3 recruited 30 MCI patients and 30 demographically-matched healthy controls. In S4, 30 healthy elders self-administered the C3B in a distracting environment and in a quiet private room in counterbalanced order. In a demonstration project, 470 consecutive primary care patients were administered the C3B as part of routine clinical care (S5).

RESULTS

C3B performance was primarily influenced by age, education, and race (S1), had acceptably high test-retest reliability and minimal practice effects (S2), discriminated MCI from healthy controls (S3), was not negatively impacted by a distracting clinical environment (S4), had high completion rates (>92%) and positive ratings from primary care patients (S5).

CONCLUSION

The C3B is a computerized cognitive screening tool that is reliable, validated, self-administered, and is conducive to integration into a busy primary care clinical workflow for detecting MCI, early Alzheimer's disease, and other related dementias.

Mobility and associations with levels of cerebrospinal fluid amyloid β and tau in a memory clinic cohort

Background

Mobility impairments, in terms of gait and balance, are common in persons with dementia. To explore this relationship further, we examined the associations between mobility and cerebrospinal fluid (CSF) core biomarkers for Alzheimer's disease (AD).

Methods

In this cross-sectional study, we included 64 participants [two with subjective cognitive decline (SCD), 13 with mild cognitive impairment (MCI) and 49 with dementia] from a memory clinic. Mobility was examined using gait speed, Mini-Balance Evaluation Systems test (Mini-BESTest), Timed Up and Go (TUG), and TUG dual-task cost (TUG DTC). The CSF biomarkers included were amyloid-β 42 (Aβ₄₂), total-tau (t-tau), and phospho tau (p-tau₁₈₁). Associations between mobility and biomarkers were analyzed through correlations and multiple linear regression analyses adjusted for (1) age, sex, and comorbidity, and (2) SCD/MCI vs. dementia.

Results

Aβ₄₂ was significantly correlated with each of the mobility outcomes. In the adjusted multiple regression analyses, Aβ₄₂ was significantly associated with Mini-BESTest and TUG in the fully adjusted model and with TUG DTC in step 1 of the adjusted model (adjusting for age, sex, and comorbidity). T-tau was only associated with TUG DTC in step 1 of the adjusted model. P-tau₁₈₁ was not associated with any of the mobility outcomes in any of the analyses.

Conclusion

Better performance on mobility outcomes were associated with higher levels of CSF Aβ₄₂. The association was strongest between Aβ₄₂ and Mini-BESTest, suggesting that dynamic balance might be closely related with AD-specific pathology.

Plasma microglial-derived extracellular vesicles are increased in frail patients with Mild Cognitive Impairment and exert a neurotoxic effect

Extracellular vesicles (EVs) are mediators of cellular communication that can be released by almost all cell types in both physiological and pathological conditions and are present in most biological fluids. Such characteristics make them attractive in the research of biomarkers for age-related pathological conditions. Based on this, the aim of the present study was to examine the changes in EV concentration and size in the context of frailty, a geriatric syndrome associated with a progressive physical and cognitive decline. Specifically, total EVs and neural and microglial-derived EVs (NDVs and MDVs respectively) were investigated in plasma of frail and non-frail controls (CTRL), mild cognitive impairment (MCI) subjects, and in Alzheimer's disease (AD) patients. Results provided evidence that AD patients displayed diminished NDV concentration (3.61 × 10⁹ ± 1.92 × 10⁹ vs 7.16 × 10⁹ ± 4.3 × 10⁹ particles/ml) and showed high diagnostic performance. They are able to discriminate between AD and CTRL with an area under the curve of 0.80, a sensitivity of 78.95% and a specificity of 85.7%, considering the cut-off of 5.27 × 10⁹ particles/ml. Importantly, we also found that MDV concentration was increased in frail MCI patients compared to CTRL (5.89 × 10⁹ ± 3.98 × 10⁹ vs 3.16 × 10⁹ ± 3.04 × 10⁹ particles/ml, P < 0.05) and showed high neurotoxic effect on neurons. MDV concentration discriminate frail MCI vs non-frail CTRL (AUC = 0.76) with a sensitivity of 80% and a specificity of 70%, considering the cut-off of 2.69 × 10⁹ particles/ml. Altogether, these results demonstrated an alteration in NDV and MDV release during cognitive decline, providing important insight into the role of EVs in frailty status.

Association between occlusal support and cognitive impairment in older Chinese adults: a community-based study

Introduction

The loss of occlusal support due to tooth loss is associated with systemic diseases. However, there was little about the association between occlusal support and cognitive impairment. The cross-sectional study aimed to investigate their association.

Methods

Cognitive function was assessed and diagnosed in 1,225 community-dwelling adults aged 60 years or older in Jing'an District, Shanghai. Participants were diagnosed with mild cognitive impairment (MCI) by Peterson's criteria, or dementia, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. We determined the number of functional occlusal supporting areas according to Eichner classifications. We used multivariate logistic regression models to analyze the relationship between occlusal support and cognitive impairment and mediation effect models to analyze the mediation effect of age.

Results

Six hundred sixty participants were diagnosed with cognitive impairment, averaging 79.92 years old. After adjusting age, sex, education level, cigarette smoking, alcohol drinking, cardiovascular disease, and diabetes, individuals with poor occlusal support had an OR of 3.674 (95%CI 1.141-11.829) for cognitive impairment compared to those with good occlusal support. Age mediated 66.53% of the association between the number of functional occlusal supporting areas and cognitive impairment.

Discussion

In this study, cognitive impairment was significantly associated with the number of missing teeth, functional occlusal areas, and Eichner classifications with older community residents. Occlusal support should be a significant concern for people with cognitive impairment.

Validation of a Computerized Cognitive Training Tool to Assess Cognitive Impairment and Enable Differentiation Between Mild Cognitive Impairment and Dementia

BACKGROUND

Age-related cognitive decline is a chronic, progressive process that requires active clinical management as cognitive status changes. Computerized cognitive training (CCT) provides cognitive exercises targeting specific cognitive domains delivered by computer or tablet. Meanwhile, CCT can be used to regularly monitor the cognitive status of patients, but it is not clear whether CCT can reliably assess cognitive ability or be used to diagnose different stages of cognitive impairment.

OBJECTIVE

To investigate whether CCT can accurately monitor the cognitive status of patients with cognitive impairment as well as distinguish patients with dementia from patients with mild cognitive impairment (MCI).

METHOD

We included 116 patients (42 dementia and 74 MCI) in final analysis. Cognitive ability was assessed by averaging the patient performance on the CCT to determine the Cognitive Index. The validity of the Cognitive Index was evaluated by its correlation with neuropsychological tests, and internal consistency was measured to assess the reliability. Additionally, we determined the diagnostic ability of the Cognitive Index to detect dementia using receiver operating characteristic (ROC) analysis.

RESULTS

The Cognitive Index was highly correlated with the Montreal Cognitive Assessment (r = 0.812) and the Mini-Mental State Examination (r = 0.694), indicating good convergent validity, and the Cronbach's alpha coefficient was 0.936, indicating excellent internal consistency. The area under the ROC curve, sensitivity, and specificity of the Cognitive Index to diagnose dementia were 0.943, 83.3%, and 91.9%, respectively.

CONCLUSIONS

CCT can be used to assess cognitive status and detect dementia in patients with cognitive impairment.

Observed Improvement in Cognition During a Personalized Lifestyle Intervention in People with Cognitive Decline

BACKGROUND

Alzheimer's disease (AD) is a chronic condition marked by progressive objective cognitive impairment (OCI). No monotherapy has substantially altered disease progression, suggesting the disease is multifactorial and may require a multimodal therapeutic approach.

OBJECTIVE

We sought to determine if cognitive function in a sample with OCI would change in response to a multimodal, individualized care plan based on potential contributors to cognitive decline (e.g., nutritional status, infection, etc.).

METHODS

Participants (n = 34) were recruited from the San Diego, CA area. The multimodal intervention included lifestyle changes (i.e., movement, diet, and stress management), nutraceutical support, and medications. It was delivered pragmatically over four clinical visits, and outcome measures were gathered at four study visits, occurring at baseline, one, three, and six months (primary endpoint). Study participants received weekly phone calls for nutrition support throughout study participation. Outcome measures included the Cambridge Brain Sciences (CBS) battery, and the Montreal Cognitive Assessment (MoCA).

RESULTS

At 6 months, mean MoCA scores improved from 19.6±3.1 to 21.7±6.2 (p = 0.013). Significant improvement was observed in mean scores of the CBS memory domain [25.2 (SD 23.3) to 35.8 (SD 26.9); p < 0.01] and CBS overall composite cognition score [24.5 (SD 16.1) to 29.7 (SD 20.5); p = 0.02]. All CBS domains improved.

CONCLUSION

Multiple measures of cognitive function improved after six months of intervention. Our results support the feasibility and impact of a multimodal, individualized treatment approach to OCI, warranting further research.

Catalpol Mitigates Alzheimer's Disease Progression by Promoting the Expression of Neural Stem Cell Exosomes Released miR-138-5p

Alzheimer's disease (Alzheimer's disease, AD) is a neurodegenerative disease characterized by senile plaque deposition and neurofibrillary tangles. The pathogenesis of AD is complicated and the drugs used to treat AD are single-targeted drugs, which can only improve or alleviate the symptoms of patients, but cannot delay or prevent the progress of the disease. Because of its ability to act on multiple targets, multiple systems, multiple links, and multiple pathways, Chinese herbal compound prescriptions have shown unique advantages in the research and treatment of AD. Our previous study has demonstrated the protect role of the Chinese medicine Rehmannia in AD. However, the underlying mechanism remains unclear. In the present study, both in vitro and vivo experiments were employed, and we found Catalpol (Ca), the main extract of Rehmannia, could mitigate AD progression both in vitro and in vivo by promoting miR-138-5p level in neural stem cell secreted exosomes.