Prevalence of Alzheimer's disease dementia in the 50 US states and 3142 counties: A population estimate using the 2020 bridged-race postcensal from the National Center for Health Statistics

Regional variation in diagnostic intensity of dementia among older U.S. adults: An observational study

INTRODUCTION

Geographic variation in diagnosed cases of Alzheimer's disease and related dementias (ADRD) could be due to underlying population risk or differences in intensity of new case identification. Areas with low ADRD diagnostic intensity could be targeted for additional surveillance efforts.

METHODS

Medicare claims were used for a cohort of older adults across hospital referral regions (HRRs). ADRD-specific regional diagnosis intensity was measured as the ratio of expected new ADRD cases (estimated using population demographics, risk factors, and practice intensity) compared to observed ADRD-diagnosed cases.

RESULTS

Crude new ADRD diagnosis rate ranged from 1.7 to 5.4 per 100 across HRRs. ADRD-specific diagnosis intensity ranged from 0.69 to 1.47 and varied most for Black, Hispanic, and the youngest (66-74) subgroups. Across all subgroups, ADRD diagnosis intensity was associated with 2-fold difference in receiving an ADRD diagnosis.

DISCUSSION

Where one resides influences the likelihood of receiving an ADRD diagnosis, particularly among those 66-74 years of age and minoritized groups.

HIGHLIGHTS

Rate of new Alzheimer's disease and related dementias (ADRD) case identification varies geographically across the United States. Variation in case identification is greatest in Black, Hispanic, and young-old groups. Intensity of diagnosis (ie, case identification) unrelated to population risk differs across place. Likelihood of receiving an ADRD diagnosis varies 2-fold based on place of residence.

Association between ambient fine particular matter components and subsequent cognitive impairment in community-dwelling older people: a prospective cohort study from eastern China

BACKGROUND

Fine particular matter (PM2.5) has been associated with dementia, but limited information is available regarding the association between PM2.5 components and dementia.

AIMS

We aimed to identify the major components of PM2.5 that affect cognitive function to further investigate its mechanism of action, and develop a prevention strategy for dementia.

METHODS

In this study, we included 7804 participants aged ≥ 60 years recruited from seven counties in Zhejiang province, eastern China. The participants completed the baseline survey between 2014 and 2015, and were followed up until the end of 2020. We adopted single-component robust Poisson regression models for analyses, and estimated relative risks and 95% confidence intervals describing associations between the chemical constituents of PM2.5 exposure and incident cognitive impairment in those who were free from cognitive impairment at baseline.

RESULTS

Significantly positive associations were observed between sulfate, nitrate, ammonium, and organic matter in PM2.5 and incident cognitive impairment across different exposure periods; the relative risks of 10-year exposure before enrollment ranged from 1.01 to 1.02. However, we did not find a significant association between black carbon and cognitive impairment. The point estimates of the relative risk values did not change substantially after performing the sensitivity analyses.

CONCLUSIONS

Our findings strengthen the idea that long-term exposure to PM2.5 mass and its chemical components is associated with an elevated risk of incident cognitive impairment among older adults.

Promoting serious illness conversations in primary care through telehealth among persons living with cognitive impairment

BACKGROUND

serious illness conversations (SIC), particularly for persons living with cognitive impairment (PLCI), inconsistently happen in primary care. Pragmatic, scalable strategies are needed to promote SIC for PLCI.

DESIGN

Pragmatic, prospective single-arm pilot study that occurred between July 1, 2021 and May 30, 2022 across seven primary care practices in North Carolina.

PARTICIPANTS

Community-dwelling patients aged 65 and older with known or probable mild cognitive impairment or dementia (with decision-making capacity) and their care partners (if available).

INTERVENTION

SIC telehealth intervention (TeleVoice) via video or telephone to assist PLCI in discussing their current goals, values, and future medical preferences, while facilitating documentation within the EHR.

MAIN OUTCOMES

Main feasibility outcomes included reach/enrollment, intervention completion, and adoption rates at the clinic and provider level. Primary effectiveness outcomes included SIC documentation and quality within the EHR and usage of advance care planning billing (ACP) codes.

RESULTS

Of the 163 eligible PLCI approached, 107 (66%) enrolled (mean age 83.7 years, 68.2% female, 16.8% Black, 22% living in a geographic area of high socioeconomic disadvantage) and 81 (76%) completed the SIC telehealth intervention; 45 care partners agreed to participate (mean age 71.5 years, 80% female). Adoption at clinic level was 50%, while 75% of providers within these clinics participated. Among PLCI that completed the intervention, SIC documentation and usage of ACP billing codes was 100% and 96%, respectively, with 96% (n = 78) having high-quality SIC documentation. No significant differences were observed between telephone and video visits.

CONCLUSION

These findings provide preliminary evidence to support the feasibility of conducting SICs through telehealth to specifically meet the needs of community-dwelling PLCI. Further investigation of the sustainability of the intervention and its long-term impact on patient and caregiver outcomes is needed.

Insulin resistance as the molecular link between diabetes and Alzheimer's disease

Diabetes mellitus (DM) and Alzheimer's disease (AD) are two major health concerns that have seen a rising prevalence worldwide. Recent studies have indicated a possible link between DM and an increased risk of developing AD. Insulin, while primarily known for its role in regulating blood sugar, also plays a vital role in protecting brain functions. Insulin resistance (IR), especially prevalent in type 2 diabetes, is believed to play a significant role in AD's development. When insulin signalling becomes dysfunctional, it can negatively affect various brain functions, making individuals more susceptible to AD's defining features, such as the buildup of beta-amyloid plaques and tau protein tangles. Emerging research suggests that addressing insulin-related issues might help reduce or even reverse the brain changes linked to AD. This review aims to explore the rela-tionship between DM and AD, with a focus on the role of IR. It also explores the molecular mechanisms by which IR might lead to brain changes and assesses current treatments that target IR. Understanding IR's role in the connection between DM and AD offers new possibilities for treatments and highlights the importance of continued research in this interdisciplinary field.

Advances in Alzheimer's disease: A multifaceted review of potential therapies and diagnostic techniques for early detection

Alzheimer's disease (AD) remains one of the most formidable neurological disorders, affecting millions globally. This review provides a holistic overview of the therapeutic strategies, both conventional and novel, aimed at mitigating the impact of AD. Initially, we delve into the conventional approach, emphasizing the role of Acetylcholinesterase (AChE) inhibition, which has been a cornerstone in AD management. As our understanding of AD evolves, several novel potential approaches emerge. We discuss the promising roles of Butyrylcholinesterase (BChE) inhibition, Tau Protein inhibitors, COX-2 inhibition, PPAR-γ agonism, and FAHH inhibition, among others. The potential of the endocannabinoids (eCB) system, cholesterol-lowering drugs, metal chelators, and MMPs inhibitors are also explored, culminating in the exploration of the pivotal role of microRNA in AD progression. Parallel to these therapeutic insights, we shed light on the novel tools and methodologies revolutionizing AD research. From the quantitative analysis of gene expression by qRTPCR to the evaluation of mitochondrial function using induced pluripotent stem cells (iPSCs), the advances in diagnostic and research tools offer renewed hope. Moreover, we explore the current landscape of clinical trials, highlighting the leading drug interventions and their respective stages of development. This comprehensive review concludes with a look into the future perspectives, capturing the potential breakthroughs and innovations on the horizon. Through a synthesis of current knowledge and emerging research, this article aims to provide a consolidated resource for clinicians, researchers, and academicians in the realm of Alzheimer's disease.

A Visualization Tool to Study Dyadic Caregiving Health Profiles

OBJECTIVES

Guided by a life course perspective and fundamental cause theory, this study aims to visualize co-trajectories of health between partners and examine how changes in one spouse's cognitive status can cohesively impact the health of the other spouse along three dimensions (functional, mental, and cognitive).

METHODS

Drawing longitudinal data from the Health and Retirement Study 2000-2016 (N = 3582), we measure women's health profiles by functional limitation (physical health), depression (mental health), and cognitive function (cognitive health). We use multivariate linear mixed models to summarize these paths in the same visual representation.

RESULTS

The approach provides a visualization tool that depicts data and model in the same spatial representation allowing assessment of model fit and comparison. This study advances the traditional life course studies by representing underlying processes as a multidimensional time vector of health outcomes.

DISCUSSION

The described approach provides a blueprint for studying complex health profiles or trajectories.

Clinical Utility of the Neuropsychological Assessment Battery Judgment Subtest in the Evaluation of Older Adults

OBJECTIVE

The purpose of this retrospective archival study was to explore the clinical utility of the Judgment subtest of the Neuropsychological Assessment Battery (NAB) in older adults who were referred because of cognitive concerns. Specifically, we were interested in how NAB Judgment covaried with other measures of executive functioning.

METHOD

226 adults, aged 61-89 years (48% dementia, 35% mild cognitive impairment, 18% cognitively intact) completed NAB Judgment. They also completed Trail Making Test (TMT) A and B. In addition, Behavior Rating Inventory of Executive Function (BRIEF-A) informant and self-reports were obtained to measure executive functioning in daily life.

RESULTS

Scores on NAB Judgment did not correlate significantly with BRIEF-A informant ratings. However, there was a statistically significant correlation between BRIEF-A informant ratings and TMT B. Better performance on TMT B was associated with fewer informant concerns. Furthermore, subgroups with versus without informant BRIEF-A Metacognition indices in the range of impairment demonstrated a statistically significant difference on TMT B but not on Judgment.

CONCLUSIONS

Executive functioning in older adults should not be assessed using NAB Judgment alone. Such an evaluation should be supplemented with other in-person tests as well as informant ratings of daily functioning.

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.

Advancements in high-resolution 3D microscopy analysis of endosomal morphology in postmortem Alzheimer's disease brains

Abnormal endo-lysosomal morphology is an early cytopathological feature of Alzheimer's disease (AD) and genome-wide association studies (GWAS) have implicated genes involved in the endo-lysosomal network (ELN) as conferring increased risk for developing sporadic, late-onset AD (LOAD). Characterization of ELN pathology and the underlying pathophysiology is a promising area of translational AD research and drug development. However, rigorous study of ELN vesicles in AD and aged control brains poses a unique constellation of methodological challenges due in part to the small size of these structures and subsequent requirements for high-resolution imaging. Here we provide a detailed protocol for high-resolution 3D morphological quantification of neuronal endosomes in postmortem AD brain tissue, using immunofluorescent staining, confocal imaging with image deconvolution, and Imaris software analysis pipelines. To demonstrate these methods, we present neuronal endosome morphology data from 23 sporadic LOAD donors and one aged non-AD control donor. The techniques described here were developed across a range of AD neuropathology to best optimize these methods for future studies with large cohorts. Application of these methods in research cohorts will help advance understanding of ELN dysfunction and cytopathology in sporadic AD.

Dementia in the Ancient Greco-Roman World Was Minimally Mentioned

Background

The possibility that Alzheimer's disease and related dementias (ADRD) is a modern disease arises from the minimal mention of advanced cognitive decline by ancient Greeks and Romans, who were mainly concerned with the physical frailties of older ages.

Objective

Because standard medical histories of elderly health lacked mention of cognitive decline, we examined texts by Greek and Roman authors that mentioned memory loss and dementia.

Methods

Primary texts of Greco-Roman authors, 8th century BCE into the 3rd century CE, that mentioned cognitive decline were identified and critically evaluated. Secondary sources were excluded.

Results

No ancient account of cognitive loss is equivalent to modern clinical data. The term dementia was occasionally used in antiquity, but not invariably linked to old age. Ancient Greeks and Romans expected intellectual competence beyond age 60. While some memory loss was acknowledged, we found only four accounts of severe cognitive loss that might represent ADRD. The possibility of modest ADRD prevalence in ancient Greece and Rome is consistent with its low prevalence in the Tsimane of Bolivia. These contemporary Amerindians live under conditions of high mortality from frequent infections and minimal cardiovascular disease with physically demanding lives. Tsimane after age 60 had increased mild cognitive impairment; the few cases of dementia were not clinically consistent with AD.

Conclusions

The modern 'epidemic level' of advanced dementias was not described among ancient Greco-Roman elderly. The possible emergence of advanced ADRD in the Roman era may be associated with environmental factors of air pollution and increased exposure to lead. Further historical analysis may formulate critical hypotheses about the modernity of high ADRD prevalence.

Performance of the Lumipulse plasma Aβ42/40 and pTau181 immunoassays in the detection of amyloid pathology

INTRODUCTION

This study evaluated the performance of the Lumipulse plasma beta-amyloid (Aβ) 42/40 and pTau181 compared to other assays to detect an abnormal amyloid-positron emission tomography (PET).

METHODS

Plasma samples from cognitively unimpaired (N = 179) and MCI/AD dementia (N = 36) individuals were retrospectively evaluated. Plasma Aβ42/40 and pTau181 were measured using the Lumipulse and Simoa immunoassays. An immunoprecipitation mass spectrometry (IP-MS) assay for plasma Aβ42/40 was also evaluated. Amyloid-PET status was the outcome measure.

RESULTS

Lumipulse and IP-MS Aβ42/40 exhibited the highest diagnostic accuracy for detecting an abnormal amyloid-PET (areas under the curve [AUCs] of 0.81 and 0.84, respectively). The Lumipulse and Simoa pTau181 assays exhibited lower performance (AUCs of 0.74 and 0.72, respectively). The Simoa Aβ42/40 assay demonstrated the lowest diagnostic accuracy (AUC 0.57). Combining Aβ42/40 and pTau181 did not significantly improve performance over Aβ42/40 alone for Lumipulse (AUC 0.83) or over pTau181 alone for Simoa (AUC 0.71).

DISCUSSION

The Lumipulse Aβ42/40 assay showed similar performance to the IP-MS Aβ42/40 assay for detection of an abnormal amyloid-PET; and both assays performed better than the two p-tau181 immunoassays. The Simoa Aβ42/Aβ40 assay was the least accurate at predicting an abnormal amyloid-PET status.

Highlights

Lumipulse plasma Aβ42/Aβ40 AUC for abnormal amyloid-PET detection was 0.81.This performance was comparable to previously reported IP-MS and higher than Simoa.Performance of Alzheimer's disease blood biomarkers varies between assays.

Developing an Instrument to Evaluate the Quality of Dementia Websites

In today's digital era, health information, especially for conditions like dementia, is crucial. This study aims to develop an instrument, demenTia wEbsite measSurement insTrument (TEST), through four steps: identifying existing instruments, determining criteria, selecting and revising measurement statements, and validating the instrument from March to August 2020. Five health informatics experts used the content validity ratio (CVR) test for validation. Thirteen evaluators compared Fleiss Kappa and intraclass correlation coefficient (ICC) values across four dementia websites using TEST and another tool, DISCERN. TEST consists of seven criteria and 25 measurement statements focusing on content quality (relevance, credibility, currency) and user experience (accessibility, interactivity, attractiveness, privacy). CVR = 1 confirmed all statements as essential. The TEST demonstrated stronger consistency and assessor agreement compared to DISCERN, measured by Fleiss Kappa and ICC. Overall, it is a robust tool for reliable and user-friendly dementia resources, ensuring health holistic information accessibility.

The intersection of social determinants of health and family care of people living with Alzheimer's disease and related dementias: A public health opportunity

In this Perspective article, we highlight current research to illustrate the intersection of social determinants of health (SDOHs) and Alzheimer's disease and related dementia (ADRD) caregiving. We then outline how public health can support ADRD family caregivers in the United States. Emerging research suggests that family care for persons with ADRD is influenced by SDOHs. Public health actions that address these intersections such as improved surveillance and identification of ADRD caregivers; building and enhancing community partnerships; advancing dementia-capable health care and related payment incentives; and reducing the stigma of dementia and ADRD caregiving can potentially enhance the health and well-being of dementia caregivers. By engaging in one or all of these actions, public health practitioners could more effectively address the myriad of challenges facing ADRD caregivers most at risk for emotional, social, financial, psychological, and health disruption.

Diet's Role in Modifying Risk of Alzheimer's Disease: History and Present Understanding

Diet is an important nonpharmacological risk-modifying factor for Alzheimer's disease (AD). The approaches used here to assess diet's role in the risk of AD include multi-country ecological studies, prospective and cross-sectional observational studies, and laboratory studies. Ecological studies have identified fat, meat, and obesity from high-energy diets as important risk factors for AD and reported that AD rates peak about 15-20 years after national dietary changes. Observational studies have compared the Western dietary pattern with those of the Dietary Approaches to Stop Hypertension (DASH), Mediterranean (MedDi), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diets. Those studies identified AD risk factors including higher consumption of saturated and total fats, meat, and ultraprocessed foods and a lower risk of AD with higher consumption of fruits, legumes, nuts, omega-3 fatty acids, vegetables, and whole grains. Diet-induced factors associated with a significant risk of AD include inflammation, insulin resistance, oxidative stress, elevated homocysteine, dietary advanced glycation end products, and trimethylamine N-oxide. The molecular mechanisms by which dietary bioactive components and specific foods affect risk of AD are discussed. Given most countries' entrenched food supply systems, the upward trends of AD rates would be hard to reverse. However, for people willing and able, a low-animal product diet with plenty of anti-inflammatory, low-glycemic load foods may be helpful.