Diversity and disparity in dementia: the impact of ethnoracial differences in Alzheimer disease

2021 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease (AD), including incidence and prevalence, mortality and morbidity, use and costs of care, and the overall impact on caregivers and society. The Special Report discusses the challenges of providing equitable health care for people with dementia in the United States. An estimated 6.2 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, the latest year for which data are available, making Alzheimer's the sixth-leading cause of death in the United States and 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 in 2020 by the COVID-19 pandemic. More than 11 million family members and other unpaid caregivers provided an estimated 15.3 billion hours of care to people with Alzheimer's or other dementias in 2020. 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 $256.7 billion in 2020. 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. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are more than three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 23 times as great. Total payments in 2021 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $355 billion. Despite years of efforts to make health care more equitable in the United States, racial and ethnic disparities remain - both in terms of health disparities, which involve differences in the burden of illness, and health care disparities, which involve differences in the ability to use health care services. Blacks, Hispanics, Asian Americans and Native Americans continue to have a higher burden of illness and lower access to health care compared with Whites. Such disparities, which have become more apparent during COVID-19, extend to dementia care. Surveys commissioned by the Alzheimer's Association recently shed new light on the role of discrimination in dementia care, the varying levels of trust between racial and ethnic groups in medical research, and the differences between groups in their levels of concern about and awareness of Alzheimer's disease. These findings emphasize the need to increase racial and ethnic diversity in both the dementia care workforce and in Alzheimer's clinical trials.

Ethnic Differences in Dementia Risk: A Systematic Review and Meta-Analysis

Background:

Globally around 50 million people have dementia. Risk factors for dementia such as hypertension and diabetes are more common in Black, Asian, and other ethnic minorities. There are also marked ethnic inequalities in care seeking, likelihood of diagnosis, and uptake of treatments for dementia. Nevertheless, ethnic differences in dementia incidence and prevalence remain under-explored.

Objective:

To examine published peer-reviewed observational studies comparing age-specific or age-adjusted incidence or prevalence rates of dementia between at least two ethnic groups.

Methods:

We searched seven databases on 1 September 2019 using search terms for ethnicity, dementia, and incidence or prevalence. We included population-based studies comparing incidence or prevalence of dementia after accounting for age of at least two ethnic groups in adults aged 18 or more. Meta-analysis was conducted for eligible ethnic comparisons.

Results:

We included 12 cohort studies and seven cross-sectional studies. Thirteen were from the US, and two studies each from the UK, Singapore, and Xinjiang Uyghur Autonomous Region in China. The pooled risk ratio for dementia incidence obtained from four studies comparing Black and White ethnic groups was 1.33 (95% CI 1.07–1.65; I-squared = 58.0%). The pooled risk ratio for dementia incidence comparing the Asian and White ethnic groups was 0.86 (95% CI 0.728–1.01; I-squared = 43.9%). There was no difference in the incidence of dementia for Latino ethnic group compared to the White ethnic group.

Conclusion:

Evidence to date suggest there are ethnic differences in risk of dementia. Better understanding of the drivers of these differences may inform efforts to prevent or treat dementia.

Why Inclusion Matters for Alzheimer’s Disease Biomarker Discovery in Plasma

Background: African American/Black adults have a disproportionate incidence of Alzheimer’s disease (AD) and are underrepresented in biomarker discovery efforts. Objective: This study aimed to identify potential diagnostic biomarkers for AD using a combination of proteomics and machine learning approaches in a cohort that included African American/Black adults. Methods: We conducted a discovery-based plasma proteomics study on plasma samples (N = 113) obtained from clinically diagnosed AD and cognitively normal adults that were self-reported African American/Black or non-Hispanic White. Sets of differentially-expressed proteins were then classified using a support vector machine (SVM) to identify biomarker candidates. Results: In total, 740 proteins were identified of which, 25 differentially-expressed proteins in AD came from comparisons within a single racial and ethnic background group. Six proteins were differentially-expressed in AD regardless of racial and ethnic background. Supervised classification by SVM yielded an area under the curve (AUC) of 0.91 and accuracy of 86%for differentiating AD in samples from non-Hispanic White adults when trained with differentially-expressed proteins unique to that group. However, the same model yielded an AUC of 0.49 and accuracy of 47%for differentiating AD in samples from African American/Black adults. Other covariates such as age, APOE4 status, sex, and years of education were found to improve the model mostly in the samples from non-Hispanic White adults for classifying AD. Conclusion: These results demonstrate the importance of study designs in AD biomarker discovery, which must include diverse racial and ethnic groups such as African American/Black adults to develop effective biomarkers.

Socioeconomic Status Mediates Racial Differences Seen Using the AT(N) Framework

OBJECTIVES

African Americans are at greater risk for developing Alzheimer's disease (AD) dementia than non-Hispanic whites. In addition to biological considerations (eg, genetic influences and comorbid disorders), social and environmental factors may increase the risk of AD dementia. This paper (1) assesses neuroimaging biomarkers of amyloid (A), tau (T), and neurodegeneration (N) for potential racial differences and (2) considers mediating effects of socioeconomic status (SES) and measures of small vessel and cardiovascular disease on observed race differences.

METHODS

Imaging measures of AT(N) (amyloid and tau positron emission tomography [PET]) structural magnetic resonance imaging (MRI), and resting state functional connectivity (rs-fc) were collected from African American (n = 131) and white (n = 685) cognitively normal participants age 45 years and older. Measures of small vessel and cardiovascular disease (white matter hyperintensities [WMHs] on MRI, blood pressure, and body mass index [BMI]) and area-based SES were included in mediation analyses.

RESULTS

Compared to white participants, African American participants had greater neurodegeneration, as measured by decreased cortical volumes (Cohen's f2 = 0.05, p < 0.001). SES mediated the relationship between race and cortical volumes. There were no significant race effects for amyloid, tau, or rs-fc signature.

INTERPRETATION

Modifiable factors, such as differences in social contexts and resources, particularly area-level SES, may contribute to observed racial differences in AD. Future studies should emphasize collection of relevant psychosocial factors in addition to the development of intentional diversity and inclusion efforts to improve the racial/ethnic and socioeconomic representativeness of AD studies. ANN NEUROL 2021;89:254-265.

Impact of Preexisting Cognitive Impairment and Race/Ethnicity on Functional Outcomes Following Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

In intracerebral hemorrhage (ICH), preexisting cognitive impairment has been identified as a risk factor for increased mortality and morbidity. However, previous studies examined predominantly White populations; therefore, the prevalence and effect of preICH cognitive impairment has not been studied in a multiethnic cohort. This limits the generalizability of previous findings. We sought to investigate the role of preexisting cognitive impairment in a multiethnic population on short-term mortality and functional outcomes after ICH.

METHODS

Patients with ICH were prospectively enrolled as cases for the GERFHS III (Genetic and Environmental Risk Factors for Hemorrhagic Stroke) Study and the Ethnic/Racial Variations of ICH (ERICH) Study. Cognitive impairment before ICH was defined as positive history of dementia or treatment with donepezil, galantamine, memantine, or rivastigmine on chart abstraction or baseline interview. Specific outcomes-modified Rankin Scale score at 3 months (0-2 versus ≥3), Barthel Index score (<100 versus 100) at 3 months, and withdrawal of care-were analyzed using multivariable logistic regression. Propensity score matching and analysis was done because of imbalances between cognitively impaired and cognitively intact groups.

RESULTS

Of the 3537 cases of ICH, 304 patients had cognitive impairment predating ICH. Cognitively impaired subjects were more likely to experience withdrawal of care during hospitalization, and for survivors, greater disability (modified Rankin Scale score of ≥3) and lower Barthel scores after ICH. After propensity score matching, preexisting cognitive impairment was associated with a lower modified Rankin Scale at 3 months in the White, Black, and Hispanic subgroups.

CONCLUSIONS

Preexisting cognitive impairment was associated with loss of independence 3-month post-ICH, when matching for risk factors of cognitive impairment, in the White, Black, and Hispanic subgroups. This suggests that preexisting cognitive impairment has a negative effect in obtaining functional independence following ICH, irrespective of race/ethnicity.

Ethnic Differences in Attending a Tertiary Dementia Clinic in Israel

Introduction: Variations in lifestyle, socioeconomic status and general health likely account for differences in dementia disparities across racial groups. Our aim was to evaluate the characteristics of Arab (AS) and Jewish (JS) subjects attending a tertiary dementia clinic in Israel.

Methods: Retrospective data regarding subjects attending the Cognitive Neurology Institute at Rambam Health Care Campus between April 1, 2010, and April 31, 2016, for complaints of cognitive decline were collected from the institutional registry. AS and consecutive JS, aged ≥50 years without a previous history of structural brain disease, were included.

Results: The records of 6,175 visits were found; 3,246 subjects were ≥50 years at the initial visit. One hundred and ninety-nine AS and consecutive JS cases were reviewed. Mean age at first visit was 68.4 ± 8.8 for AS and 74.3 for JS (p < 0.0001). Mean education was 7.7 ± 4.8 years for AS and 11.3 years for JS (p < 0.0001). Mean duration of cognitive complaints prior to first visit did not differ between the groups. Initial complaints of both ethnicities were failing memory (97%) and behavioral changes (59%). Functional impairment was reported by 59% of AS and 45% of JS (p = 0.005). MMSE on first evaluation was 19.2 ± 7 for AS and 23.1 ± 5.9 for JS; p = 0.001. Alzheimer's disease was diagnosed in 32% AS and 23% JS, mild cognitive impairment in 12% AS and 21% JS. Normal cognition was diagnosed in 2% AS and 9% JS; p = 0.0001.

Conclusions: Compared to JS, AS attend a tertiary clinic when their cognitive impairment already affects their functional abilities providing a comprehensive benchmark for social health care interventions to reduce disparities.

Plasma Biomarkers of Alzheimer's Disease in African Americans

Background/Objective:

The aim of this study was to determine if plasma concentrations of 5 surrogate markers of Alzheimer’s disease (AD) pathology and neuroinflammation are associated with disease status in African Americans.

Methods:

We evaluated 321 African Americans (159 AD, 162 controls) from the Florida Consortium for African-American Alzheimer’s Disease Studies (FCA³DS). Five plasma proteins reflecting AD neuropathology or inflammation (Aβ₄₂, tau, IL6, IL10, TNFα) were tested for associations with AD, age, sex, APOE and MAPT genotypes, and for pairwise correlations.

Results:

Plasma tau levels were higher in AD when adjusted for biological and technical covariates. APOEɛ4 was associated with lower plasma Aβ₄₂ and tau levels. Older age was associated with higher plasma Aβ₄₂, tau, and TNFα. Females had lower IL10 levels. Inflammatory proteins had strong pairwise correlations amongst themselves and with Aβ₄₂.

Conclusion:

We identified effects of demographic and genetic variants on five potential plasma biomarkers in African Americans. Plasma inflammatory biomarkers and Aβ₄₂ may reflect correlated pathologies and elevated plasma tau may be a biomarker of AD in this population.

Comparing fluid biomarkers of Alzheimer's disease between African American or Black African and white groups: A systematic review and meta-analysis

RATIONALE

Biomarker research for Alzheimer's disease (AD) has grown rapidly in recent years, ensuing the integration of the AD fluid biomarker profile: Aβ1-42, t-tau, and p-tau₁₈₁, into clinical and research criteria. However, current insights of AD arise almost exclusively from studies on white individuals. Some studies have revealed that epidemiology, clinical features, and genetics of AD show variations between individuals from black and white backgrounds, conveying the importance of ethnoracial differences, and the possibility of such differences also influencing AD biomarker levels. This systematic review explored whether AD fluid biomarker levels differ between African American (AA) or Black African and white groups.

AIM

To compare AD fluid biomarkers (Aβ1-42, p-tau₁₈₁, and t-tau) levels between AA or Black Africans and white individuals.

METHOD

PubMed, Scopus, and other sources were explored for studies that quantified AD biomarkers in biological fluid from whites and AA or Black African groups. Meta-analyses were performed to find the standardized mean difference for biomarkers that were quantified in ≥3 studies.

RESULTS

Five studies were included; studies on Black Africans were not found. The meta-analyses found CSF t-tau and p-tau₁₈₁ were consistently lower in AA than white individuals, in samples with normal cognition or with mild cognitive impairment/dementia.

CONCLUSIONS

The meta-analyses found significant differences for CSF tau between AA and white individuals with normal cognition and within the dementia spectrum, expressing the importance of taking into account ethnoracial factors when interpreting CSF AD biomarkers levels. However, the generalisability of these differences is restricted by small samples' size, lack of unified methodologies and recruitment's biases within studies; further large multicentre studies with harmonized protocols and sufficient power are imperative to investigate the extent of ethnoracial differences across the spectrum of cognitive decline, with vaster efforts necessary to diversify recruitment.

Inclusion of African American/Black adults in a pilot brain proteomics study of Alzheimer's disease

Alzheimer's disease (AD) disproportionately affects certain racial and ethnic subgroups, such as African American/Black and Hispanic adults. Genetic, comorbid, and socioeconomic risk factors contribute to this disparity; however, the molecular contributions have been largely unexplored. Herein, we conducted a pilot proteomics study of postmortem brains from African American/Black and non-Hispanic White adults neuropathologically diagnosed with AD compared to closely-matched cognitively normal individuals. Examination of hippocampus, inferior parietal lobule, and globus pallidus regions using quantitative proteomics resulted in 568 differentially-expressed proteins in AD. These proteins were consistent with the literature and included glial fibrillary acidic protein, peroxiredoxin-1, and annexin A5. In addition, 351 novel proteins in AD were identified, which could partially be due to cohort diversity. From linear regression analyses, we identified 185 proteins with significant race x diagnosis interactions across various brain regions. These differences generally were reflective of differential expression of proteins in AD that occurred in only a single racial/ethnic group. Overall, this pilot study suggests that disease understanding can be furthered by including diversity in racial/ethnic groups; however, this must be done on a larger scale.

Taking the Test: A Qualitative Analysis of Cultural and Contextual Factors Impacting Neuropsychological Assessment of Xhosa-Speaking South Africans

Objective

There is an urgent need to make neuropsychological (NP) testing more acceptable, accessible, and culturally salient, particularly for culturally, educationally, and linguistically diverse individuals from countries who may have little-to-no experience with NP testing. In settings with limited resources such as South Africa, unique cultural and contextual factors (e.g., structural inequality, poverty) may impact the experience of NP evaluation. Research in this area is limited and requires further exploration. This qualitative study explores the role of cultural and contextual factors that may impact the experience of NP evaluation in a sample of Xhosa-speaking South African adults. Participant interviews explored the context from which individuals arrived at the NP assessment (e.g., quality of education, understanding of cognitive disorders), and their experience of completing NP tests.

Method

This qualitative study used data from semistructured interviews to conduct a thematic analysis exploring contextual factors and the experience of completing NP tests for the first time among Xhosa-speaking South African adults (N = 22). Results: Although no participants had prior experience with NP testing, most found testing procedures acceptable. Most participants, however, reported a limited understanding of the purpose of NP testing and cognitive problems. Additionally, some participants reported perceptions and attitudes that could affect test performance, such as misinterpreting standard testing procedures (e.g., no feedback from the examiner, being stopped mid-task) as indicative of poor performance.

Conclusions

This study provided much needed exploration into unique cultural factors that may impact the experience of NP assessment in South Africa, which could bias test performance and interpretation, and may aid the field of cross-cultural NP in better serving culturally and linguistically diverse populations. In these countries, neuropsychologists may need to actively evaluate participants’ understanding of NP testing to help foster optimal assessment conditions. They may also need to educate participants on possible causes of cognitive disorders.

Earning the Trust of African American Communities to Increase Representation in Dementia Research

Black/African American populations are underrepresented as participants in dementia research. A major barrier to participation of African American older adults in dementia research is a tendency to distrust research institutions owing to both historical and contemporary racism. Building on the Ford framework, the objective of our study was to examine factors that influence participation in dementia research among African American older adults and caregivers, with an emphasis on understanding factors related to trust. Data were collected during January 2019 and March 2020 from 10 focus groups with African American older adults (n=91), 5 focus groups with caregivers (n=44), and interviews with administrators of community-based organizations (n=11), and meetings with our Community Advisory Board. Inductive/deductive content analysis was used to identify themes. The results identified an overall tension between distrust of researchers and a compelling desire to engage in dementia research. This overarching theme was supported by six themes that provided insights about the multiple layers of distrust, as well as expectations about the appropriate conduct of researchers and academic institutions. Strong commitment to the community was identified as a priority. The findings suggest that a paradigm shift is needed to increase the representation of African Americans in dementia research. In this new paradigm, earning the trust of African American communities becomes a systemic endeavor, with academic, state, and national institutions deeply committed to earning the trust of African American communities and guiding researchers in this endeavor. The findings also generated actionable recommendations to help improve representation of African American older adults in dementia research.

Dysregulation of Endothelin-1: Implications for Health Disparities in Alzheimer's Disease

Alzheimer's disease (AD) and related dementias disproportionately impact racial and ethnic minorities. The racial and ethnic disparities in AD could be explained by differences in cerebral vascular disease pathology. Endothelin-1 (ET-1) is a potent vasoconstrictive peptide that regulates smooth muscle, endothelial cell, and pericyte contractions that may result in cerebral vascular constriction, leading to cerebral hypoperfusion; over time, ET-1 may result in neuronal injury contributing to the pathology of AD. Upregulation of the ET-1 system has been observed in African Americans when compared with non-Hispanic Whites. The role of the ET-1 system as a driver of ethnic disparities in AD requires further investigation. Targeting of the ET-1 system as a therapeutic intervention that could impact AD progression also needs further study. Dysregulation of ET-1 in Hispanic/Latino populations largely have been unexplored. Genetics linking ET-1 dysregulation and racial disparities in AD also needs further investigation. In this review, I examine how AD effects underserved minority populations and how dysregulation of the ET-1 system specifically predisposes ethnic minorities to AD. In addition, I examine the molecular interactions of the ET-1 system and amyloid beta, the role the ET-1 system in neurodegeneration, potential therapeutics for ET-1 dysregulation, and the impact on AD progression.

Race Disparities in the Use of Prevention, Screening, and Monitoring Services in Michigan Medicare Beneficiaries With Type 2 Diabetes and Combinations of Multiple Chronic Conditions

People with diabetes need routine health care to prevent potential exacerbations of diabetes and detect or prevent the development of additional chronic conditions that can worsen the course of diabetes. Using 2012 Medicare claims data from the State of Michigan for 443,932 beneficiaries with type 2 diabetes, we determined that there are differences between white and racial/ethnic minority people with diabetes in accessing any preventive care and in the amount of service used once they do access care, even after adjusting for the presence of multiple chronic conditions.

Life-Course Individual and Neighborhood Socioeconomic Status and Risk of Dementia in the Atherosclerosis Risk in Communities Neurocognitive Study

We examined associations of individual- and neighborhood-level life-course (LC) socioeconomic status (SES) with incident dementia in the Atherosclerosis Risk in Communities cohort. Individual- and neighborhood-level SES were assessed at 3 life epochs (childhood, young adulthood, midlife) via questionnaire (2001-2002) and summarized into LC-SES scores. Dementia was ascertained through 2013 using cognitive exams, telephone interviews, and hospital and death certificate codes. Cox regression was used to estimate hazard ratios of dementia by LC-SES scores in race-specific models. The analyses included data from 12,599 participants (25% Black) in the United States, with a mean age of 54 years and median follow-up of 24 years. Each standard-deviation greater individual LC-SES score was associated with a 14% (hazard ratio (HR) = 0.86, 95% confidence interval (CI): 0.81, 0.92) lower risk of dementia in White and 21% (HR = 0.79, 95% CI: 0.71, 0.87) lower risk in Black participants. Education was removed from the individual LC-SES score and adjusted for separately to assess economic factors of LC-SES. A standard-deviation greater individual LC-SES score, without education, was associated with a 10% (HR = 0.90, 95% CI: 0.84, 0.97) lower dementia risk in White and 15% (HR = 0.85, 95% CI: 0.76, 0.96) lower risk in Black participants. Neighborhood LC-SES was not associated with dementia. We found that individual LC-SES is a risk factor for dementia, whereas neighborhood LC-SES was not associated.

The Prevalence of Mild Cognitive Impairment in a Convenience Sample of 202 Gulf War Veterans

Gulf War Illness (GWI) is a chronic, multisymptom disorder estimated to affect approximately 25–32% of Gulf War veterans (GWVs). Cognitive dysfunction is a common symptom of GWI. On the continuum of cognitive decline, mild cognitive impairment (MCI) is conceptualized as a transitional phase between normal aging and dementia. Individuals with MCI exhibit cognitive decline but have relatively spared activities of daily function and do not meet criteria for dementia. The current study sought to investigate the prevalence of MCI in a convenience sample of 202 GWVs (median age: 52 years; 18% female). Twelve percent of the sample (median age: 48 years) had MCI according to an actuarial neuropsychological criterion, a rate materially higher than expected for this age group. GWVs with MCI also had a smaller hippocampal volume and a thinner parietal cortex, higher rates of current posttraumatic stress disorder and major depressive disorder compared to GWVs without MCI. Because people with MCI are more likely to progress to dementia compared to those with normal cognition, these results may portend future higher rates of dementia among deployed GWVs.

Representation of Older Latinxs in Cohort Studies at the Rush Alzheimer's Disease Center

The Rush Alzheimer's Disease Center (RADC) conducts 5 harmonized prospective clinical-pathologic cohort studies of aging - with 1 study, the Latino Core, focused exclusively on Latinxs, 2 studies consisting of mostly non-Latinx whites, and 2 studies of mostly non-Latinx blacks. This paper contextualizes the Latino Core within the other 4 harmonized RADC cohort studies. The overall aim of the paper is to provide information from the RADC, so that researchers can learn from our participants and procedures to better advance the science of Alzheimer's disease and related dementias in Latinxs. We describe an annual clinical evaluation that assesses risk factors for Alzheimer's dementia among older adults without known dementia at enrollment. As all RADC cohort studies offer brain donation as a part of research participation, we discuss our approach to brain donation and subsequent participant decision-making among older Latinxs. We also summarize baseline characteristics of older Latinxs across the 5 RADC cohort studies in relation to the baseline characteristics of non-Latinx blacks and non-Latinx whites. Finally, we outline challenges and considerations as well as potential next steps in cognitive aging research with older Latinxs.

Preliminary Efficacy of a Recruitment Educational Strategy on Alzheimer's Disease Knowledge, Research Participation Attitudes, and Enrollment Among Hispanics

INTRODUCTION

Hispanics remain underrepresented in dementia clinical research. This one-arm trial aimed to assess the preliminary efficacy of a culturally tailored recruitment educational strategy among Hispanic older adults on dementia knowledge, research participation attitudes, and enrollment.

METHOD

The recruitment strategy included 6 one-session culturally tailored dementia education events at trusted community senior centers. Participants received a pre-post survey including a 5-point Likert-type scale and the Epidemiology/Etiology Disease Scale to assess dementia knowledge, and a 4-point Likert-type scale assessing research participation attitudes. We gave participants contact information slips to complete if interested in dementia research. We also tracked participants' enrollment into the National Alzheimer's Coordinating Center Cohort.

RESULTS

Dementia knowledge increased 0.9 points (5-point Likert-type scale) and 2.2 points (epidemiology/etiology disease scale, p < .001). Interest in participating in dementia research increased from 61.7% to 80.9% (p = .039), 64.0% returned their contact information slips, and 41.1% successfully enrolled into the National Alzheimer's Coordinating Center Cohort.

CONCLUSION

A recruitment strategy including culturally tailored dementia education improves dementia knowledge, research participation attitudes, and enrollment among Hispanic older adults.

Evaluation of Public Health Messages Promoting Early Detection of Dementia Among Adult Latinos With a Living Older Adult Parental Figure

INTRODUCTION

We aimed to evaluate the resonance of public health messages promoting early detection of dementia in adult Latinos with a living older adult loved one.

METHOD

We conducted a mixed-methods study with focus groups and surveys to evaluate eight messages encouraging Latino adults to accompany their older loved one for cognitive assessment. Qualitative data were transcribed and coded, and thematic analysis was conducted. We used descriptive statistics for quantitative data.

RESULTS

Participants suggested that messages need to be translated into Spanish and images need to be more natural, present balance between positive and serious facial expressions, show more ethnic/racial diversity, and show family members other than the parents. Five major sociocultural themes affected how the messages were received: stigma, gender roles, the importance of the mother figure, guilt, and family togetherness.

CONCLUSION

Public health messages targeting cultural values are needed to effectively encourage early dementia detection in Latinos. Findings can be used to adapt culturally appropriate public health messages encouraging early dementia detection in Latinos.

The Role of Nutrition and Inflammation on Cognition in a High-Risk Group for Alzheimer's Disease

Background:

Alzheimer’s disease (AD) is a prevalent neurodegenerative disease. Treatments are necessary to target people at high risk for AD. Inflammation, particularly tumor necrosis factor alpha (TNFα), appears to be an important marker associated with the development of AD pathophysiology. Consuming a high-fat diet induces tissue expression of TNFα.

Objective:

This study investigates the relationship between nutrition, circulating inflammation, and cognition in African American women (age: M = 59.5 (±8.20) [42–73] years) at risk for developing AD.

Methods:

Participants were split into high-fat and low-fat groups based on total dietary fat consumption self-reported on the Lower Mississippi Delta Nutrition Intervention Research Initiative Food Frequency Questionnaire (Delta NIRI FFQ).

Results:

A high-fat diet was associated with increased blood serum TNFα (p = 0.02) compared to the low-fat diet. In addition, global cognition scores were 9.0% better in those who consumed a higher fat diet (p = 0.04). No significant differences across groups were noted for executive function, dual-tasking, and visuospatial performance.

Conclusion:

These results indicate that there may be multiple biological pathways involved in AD development, suggesting the need for more holistic approaches to mitigate AD-development risk.

Racial Differences in Respite Use among Black and White Caregivers for People Living with Dementia

Objectives: To examine racial differences in respite utilization among a nationally representative sample of caregivers for persons living with dementia (PLwD). A secondary aim identified factors associated with respite utilization. Methods: Using data from the 2015 National Health and Aging Trends Study and National Study of Caregiving, we conducted binary logistic regression to examine racial difference in respite use among Black and white caregivers ( n = 750). Results: 22% of the sample used respite for PLwD. Black dementia caregivers were 69% less likely (odds ratio: .31, p = .001) to use respite compared to white caregivers. Other factors associated with utilization included education, receiving help with caregiving, and providing care for more self-care/mobility tasks or to a Medicaid-enrollee. Discussion: Findings suggest that Black dementia caregivers may be at risk for less frequent use of respite and highlight the need to identify factors that promote respite use.

Obstructive sleep apnea treatment disparities among older adults with neurological disorders

OBJECTIVE

The objective of the study was to characterize obstructive sleep apnea treatment patterns among older Americans with neurological conditions.

SETTING AND PARTICIPANTS

Claims data from a 5% fee-for-service sample of Medicare beneficiaries were analyzed to determine the proportion of older adults with OSA who received and were adherent to continuous positive airway pressure therapy and examine potential gaps in OSA care among neurological populations. Logistic regression was used to determine whether gender or race/ethnicity modified the associations between neurological morbidities and OSA treatment or adherence.

RESULTS

Data from n = 102,618 beneficiaries with OSA were identified. The prevalence of stroke, cognitive disorders, or Parkinson's disease in this sample was 7%, 3%, and 2% respectively. Overall, OSA-diagnosed individuals (73%) obtained treatment, and most treated were adherent to CPAP (72%). Lower proportions of OSA treatment and adherence were observed in neurological conditions, particularly stroke. In logistic regression models, gender and race/ethnicity each modified associations between neurological comorbidity and OSA treatment and adherence. Women as compared to men with a given neurological condition were uniformly less likely to receive CPAP or adhere to treatment (P < .01 for each condition). Similarly, in comparison to whites with the same neurological condition, OSA treatment was significantly lower among all other races with stroke, and among blacks with cognitive disorders.

CONCLUSIONS

Older women and minorities with neurological conditions may be more vulnerable to gaps in OSA care. Targeted strategies to improve treatment disparities and neurological outcomes in older adults could be informed by these data.

Racial and Ethnic Differences in Alzheimer's Disease Knowledge Among Community-Dwelling Middle-Aged and Older Adults in Florida

Objective: To compare Alzheimer's disease (AD) knowledge by race and ethnicity in a community sample of middle-aged and older adults aged 50 and over in Florida. Method: Data from HealthStreet, a University of Florida community engagement program, which uses community health workers to assess the health conditions, concerns, and knowledge of community members, was used (n = 842). A multivariate regression model was used to quantify differences in AD knowledge by race and ethnicity. Results: Older age and recruitment from Miami were associated with higher AD knowledge while being non-Hispanic Black, reporting male sex, having less than high school diploma, and reporting food insecurity were associated with lower AD knowledge. Discussion: Hispanics had comparable AD knowledge to non-Hispanic Whites and more knowledge than non-Hispanic Blacks after adjusting for other factors that could differentiate these groups. Almost half of the participants did not know hypertension is a risk factor for AD, highlighting a point of intervention.

Building a National Program for Pilot Studies of Embedded Pragmatic Clinical Trials in Dementia Care

Sixteen million caregivers currently provide care to more than 5 million persons living with dementia (PLWD) in the United States. Although this population is growing and highly complex, evidence-based management remains poorly integrated within healthcare systems. Therefore, the National Institute on Aging IMPACT Collaboratory was formed to build the nation's ability to conduct embedded pragmatic clinical trials (ePCTs) for PLWD and their caregivers. The pilot core of the IMPACT Collaboratory seeks to provide funds for upward of 40 pilots for ePCTs to accelerate the testing of nonpharmacologic interventions with the goal that these pilots lead to full-scale ePCTs and eventually the embedding of evidence-based care into healthcare systems. The first two challenges for the pilot core in building the pilot study program were (1) to develop a transparent, ethical, and open nationwide process for soliciting, reviewing, and selecting pilot studies; and (2) to begin the process of describing the necessary components of a pilot study for an ePCT. During our initial funding cycle, we received 35 letters of intent, of which 17 were accepted for a full proposal and 14 were submitted. From this process we learned that investigators lack knowledge in ePCTs, many interventions lack readiness for an ePCT pilot study, and many proposed studies lack key pragmatic design elements. We therefore have set three key criteria that future pilot studies must meet at a minimum to be considered viable. We additionally discuss key design decisions investigators should consider in designing a pilot study for an ePCT. J Am Geriatr Soc 68:S14-S20, 2020.

Sources of Caregiving Burden in Middle-Aged and Older Latino Caregivers

OBJECTIVE

We aimed to identify sources of caregiver burden in middle-aged and older Latino caregivers of people with Alzheimer disease and related dementia (ADRD).

METHODS

Participants were recruited through an agreement with the Rush Alzheimer's Disease Center Clinic Data Repository. We conducted semistructured interviews with 16 middle-aged and older Latinos who were the primary caregiver for a family member diagnosed with ADRD. The interview guide consisted of questions and probes to capture participants' perceptions of family caregiving. Direct content analysis was performed.

RESULTS

Participants were aged 50 to 75 years (n = 16) and a majority female (n = 12). The sources of burden identified were (1) caregiver responsibilities, (2) caregiving-related health decline, (3) lack of support, (4) financial status, (5) vigilance, and (6) concerns about the future.

CONCLUSIONS

The influence of gender roles seemed to play a role in caregivers' perceptions of sources of burden, especially on caregiver responsibilities and perceptions of lack of support. Latinos cultural values such as familismo and marianismo likely reinforced gender disparities in family caregiving.

Promoting dementia awareness in African-American faith communities

INTRODUCTION

Alzheimer's disease and other dementia-related disorders are affecting the African-American community at alarming rates. African-American churches have traditionally been places of refuge where families go for support. However, many churches lack programs or resources to support families affected by dementia. In response, a nurse-led interdisciplinary collaborative partnered with churches to promote dementia awareness through education.

PURPOSE

The purpose of this analysis was to (a) describe the demographics of those seeking dementia education in African-American faith communities; (b) identify prior knowledge of dementia community resources; and (c) determine the preliminary usefulness of the education provided.

METHODS

Over the course of 16 months, 202 individuals attended nine educational sessions hosted by five churches across metropolitan Atlanta. Quantitative surveys were used to collect demographics and evaluate the educational sessions.

RESULTS

The majority of attendees were African-American adults (91%), women (75%), and unaware of dementia resources (66%). Several attendees identified themselves as church leaders, community/church members, caregivers, and/or healthcare professionals. Attendees expressed the educational content was applicable to themselves or their families.

CONCLUSION

Results help identify ways to alter and/or strengthen the educational content and serve as a guide for developing culturally relevant, faith-based community programs.

Racially diverse participant registries to facilitate the recruitment of African Americans into presymptomatic Alzheimer's disease studies

INTRODUCTION

The Alzheimer's Disease Prevention Registry (ADPR) of the Joseph and Kathleen Bryan Alzheimer's Disease Research Center at Duke University has been successful in achieving a racially diverse and "research ready" cohort of cognitively healthy volunteers.

METHODS

The ADPR is based on an infrastructure that includes: (1) an administrative leadership team; (2) a coordinating center; (3) an IT management team; (4) a community engagement team; and (5) collaborations with study partners across disciplines.

RESULTS

The ADPR currently has more than 4677 members, 26% of whom are African American. The ADPR has supported 21 studies including 8 biomarker studies, 7 clinical trials, 4 cognitive neuroscience studies, and 2 studies assessing novel computerized measures.

DISCUSSION

We describe our experiences establishing and maintaining a diverse ADPR as well as insights on recruitment strategies to increase the representation of African Americans in Alzheimer's disease studies.

The influence of diversity on the measurement of functional impairment: An international validation of the Amsterdam IADL Questionnaire in eight countries

INTRODUCTION

To understand the potential influence of diversity on the measurement of functional impairment in dementia, we aimed to investigate possible bias caused by age, gender, education, and cultural differences.

METHODS

A total of 3571 individuals (67.1 ± 9.5 years old, 44.7% female) from The Netherlands, Spain, France, United States, United Kingdom, Greece, Serbia, and Finland were included. Functional impairment was measured using the Amsterdam Instrumental Activities of Daily Living (IADL) Questionnaire. Item bias was assessed using differential item functioning (DIF) analysis.

RESULTS

There were some differences in activity endorsement. A few items showed statistically significant DIF. However, there was no evidence of meaningful item bias: Effect sizes were low (ΔR 2 range 0-0.03). Impact on total scores was minimal.

DISCUSSION

The results imply a limited bias for age, gender, education, and culture in the measurement of functional impairment. This study provides an important step in recognizing the potential influence of diversity on primary outcomes in dementia research.

Subjective Memory Complaints in White and African American Participants

OBJECTIVE

Subjective memory complaints (SMCs) are associated with mild cognitive impairment and dementia but are understudied in African Americans (AAs). We compared SMC endorsement in white and AA participants and evaluated predictors of diagnostic progression.

METHODS

Initial visit variables, including SMC and memory performance, were compared within a cognitively normal race-matched sample of white and AA participants (N_total = 912; 456_{each race}) to assess the presence and predictors of SMC, the predictors of future diagnostic progression, and the change in memory performance over time.

RESULTS

More white (32.9%) than AA (24.3%) participants reported SMC (P < .01, ϕ = -.10). Subjective memory complaint was predicted by memory performance (B = -0.03, standard error [SE] = 0.013, odds ratio [OR] = .968, P < .05) and race (B = -0.99, SE = 0.080, OR = .373, P < .001). Subjective memory complaints and memory performance were associated with progression, χ² (3, n = 912) = 102.37, P < .001. African American race (-2.05 ± 0.24 SE) and SMC (-0.45 ± 0.21 SE) were associated with worse memory performance at baseline and over time, χ²(3) = 13.54, P < .01.

CONCLUSIONS

In contrast to previous research, our study found that SMC is associated with diagnostic progression and objective memory declines in both white and AA participants.

Popular three-dimensional models: Advantages for cancer, Alzheimer's and cardiovascular diseases

The increasing prevalence of non-communicable diseases, namely cancer, Alzheimer's (AD) and cardiovascular diseases (CVDs), worldwide continues to be a major health burden. Research attempts have been made to understand the pathophysiology and develop effective therapeutic agents for these diseases using conventional in vitro and ex vivo models. Due to the complexity of human disease mechanisms, often these models fail to recapitulate clinically relevant pathologies. As such, interests are arising in the exploration of three-dimensional (3D) in-vitro models, which create an artificial environment to closely mimic in vivo human conditions. Several studies have developed 3D models for cancer, AD and CVD research which can greatly improve the understanding of biological mechanisms and mirror clinical drug activities. Thus, 3D cultures may provide new in-vitro models that recapitulate the architecture and biological mechanisms of human diseases prior to the need for the use of sentient animals.

2020 Alzheimer's disease facts and figures

This article describes the public health impact of Alzheimer's disease (AD), including incidence and prevalence, mortality and morbidity, use and costs of care, and the overall impact on caregivers and society. The Special Report discusses the future challenges of meeting care demands for the growing number of people living with Alzheimer's dementia in the United States with a particular emphasis on primary care. By mid-century, the number of Americans age 65 and older with Alzheimer's dementia may grow to 13.8 million. This represents a steep increase from the estimated 5.8 million Americans age 65 and older who have Alzheimer's dementia today. Official death certificates recorded 122,019 deaths from AD in 2018, the latest year for which data are available, making Alzheimer's the sixth leading cause of death in the United States and the fifth leading cause of death among Americans age 65 and older. Between 2000 and 2018, deaths resulting from stroke, HIV and heart disease decreased, whereas reported deaths from Alzheimer's increased 146.2%. In 2019, more than 16 million family members and other unpaid caregivers provided an estimated 18.6 billion hours of care to people with Alzheimer's or other dementias. This care is valued at nearly $244 billion, but its costs extend to family caregivers' increased risk for emotional distress and negative mental and physical health outcomes. Average per-person Medicare payments for services to beneficiaries age 65 and older with AD or other dementias are more than three times as great as payments for beneficiaries without these conditions, and Medicaid payments are more than 23 times as great. Total payments in 2020 for health care, long-term care and hospice services for people age 65 and older with dementia are estimated to be $305 billion. As the population of Americans living with Alzheimer's dementia increases, the burden of caring for that population also increases. These challenges are exacerbated by a shortage of dementia care specialists, which places an increasing burden on primary care physicians (PCPs) to provide care for people living with dementia. Many PCPs feel underprepared and inadequately trained to handle dementia care responsibilities effectively. This report includes recommendations for maximizing quality care in the face of the shortage of specialists and training challenges in primary care.

Bilingualism Is Associated with a Delayed Onset of Dementia but Not with a Lower Risk of Developing it: a Systematic Review with Meta-Analyses

Some studies have linked bilingualism with a later onset of dementia, Alzheimer's disease (AD), and mild cognitive impairment (MCI). Not all studies have observed such relationships, however. Differences in study outcomes may be due to methodological limitations and the presence of confounding factors within studies such as immigration status and level of education. We conducted the first systematic review with meta-analysis combining cross-sectional studies to explore if bilingualism might delay symptom onset and diagnosis of dementia, AD, and MCI. Primary outcomes included the age of symptom onset, the age at diagnosis of MCI or dementia, and the risk of developing MCI or dementia. A secondary outcome included the degree of disease severity at dementia diagnosis. There was no difference in the age of MCI diagnosis between monolinguals and bilinguals [mean difference: 3.2; 95% confidence intervals (CI): -3.4, 9.7]. Bilinguals vs. monolinguals reported experiencing AD symptoms 4.7 years (95% CI: 3.3, 6.1) later. Bilinguals vs. monolinguals were diagnosed with dementia 3.3 years (95% CI: 1.7, 4.9) later. Here, 95% prediction intervals showed a large dispersion of effect sizes (-1.9 to 8.5). We investigated this dispersion with a subgroup meta-analysis comparing studies that had recruited participants with dementia to studies that had recruited participants with AD on the age of dementia and AD diagnosis between mono- and bilinguals. Results showed that bilinguals vs. monolinguals were 1.9 years (95% CI: -0.9, 4.7) and 4.2 (95% CI: 2.0, 6.4) older than monolinguals at the time of dementia and AD diagnosis, respectively. The mean difference between the two subgroups was not significant. There was no significant risk reduction (odds ratio: 0.89; 95% CI: 0.68-1.16) in developing dementia among bilinguals vs. monolinguals. Also, there was no significant difference (Hedges' g = 0.05; 95% CI: -0.13, 0.24) in disease severity at dementia diagnosis between bilinguals and monolinguals, despite bilinguals being significantly older. The majority of studies had adjusted for level of education suggesting that education might not have played a role in the observed delay in dementia among bilinguals vs. monolinguals. Although findings indicated that bilingualism was on average related to a delayed onset of dementia, the magnitude of this relationship varied across different settings. This variation may be due to unexplained heterogeneity and different sources of bias in the included studies. Registration: PROSPERO CRD42015019100.

Ethnoracial Differences in Lewy Body Diseases with Cognitive Impairment

BACKGROUND

Increasing research focuses on ethnic differences in Alzheimer's disease, but such efforts in other neurodegenerative dementias are lacking. Currently, data on the ethnic profile of cognitively impaired persons with Lewy body disease (LBD) is limited, despite Lewy body dementia being the second most common neurodegenerative dementia.

OBJECTIVE

The study aimed to investigate presenting characteristics among ethnoracially diverse individuals with cognitive impairment secondary to LBD using the National Alzheimer's Coordinating Center database.

METHODS

Participants self-identified as African American, Hispanic, or White. We used Kruskal-Wallis and Pearson χ2 analyses to investigate group differences in presenting characteristics and linear regression to compare neuropsychological test performance.

RESULTS

Presentation age was similar between groups (median 74-75 years). Compared to Whites (n = 1782), African Americans (n = 130) and Hispanics (n = 122) were more likely to be female and single, have less educational attainment, report more cardiovascular risk factors, describe less medication use, and perform worse on select cognitive tests. Hispanics reported more depressive symptoms.

CONCLUSION

Cohorts differences highlight the need for population-based LBD studies with racial-ethnic diversity. Culturally-sensitive neuropsychological tests are needed to determine whether observed differences relate to cultural, social, testing, or disease-related factors. More research is needed regarding how social and biological factors impact LBD care among diverse populations.

Effect of Mentally Challenging Occupations on Incident Dementia Differs Between African Americans and Non-Hispanic Whites

BACKGROUND

Engaging in mentally challenging activities may protect against dementia in late life. However, little is known whether the association between mentally challenging activities and dementia risk varies with race/ethnicity.

OBJECTIVE

The current study investigates whether having jobs with higher mental stimulation is differentially associated with a decreased risk of dementia between African Americans (AAs) and non-Hispanic Whites (nHWs).

METHODS

The sample consisted of 1,079 individuals (66% nHWs, 28% AAs; age = 78.6±5.3) from the longitudinal Einstein Aging Study. Occupation information of each participant was collected retrospectively at baseline and was linked to the substantive complexity of work score from the Dictionary of Occupational Titles. Cox proportional hazards models were used to evaluate the associations of occupational complexity with risk of dementia.

RESULTS

Individuals whose jobs had moderate-to-high levels of complexity, compared to those with the lowest complexity, were at modestly decreased risk for incident dementia. When stratified by race, moderate-to-high levels of occupational complexity were significantly associated with lower risk of developing dementia for AAs (HR = 0.35). When risk of dementia was evaluated based on the combinations of race×occupational complexity, AAs with lowest occupational complexity showed the highest risk of developing dementia, while other combinations exhibited lower risk of developing dementia (HRs = 0.36~0.43).

CONCLUSION

Our results suggest that moderate-to-high levels of complexity at work are associated with a decreased risk of incident dementia in AAs. Understanding the differential effects of mentally challenging occupations across race/ethnicity may suggest important intervention strategies that could mitigate racial disparities in dementia rates.

Combined Influences of Dementia Exposure and Personality on Self-Reported Memory Problems

The current study investigated whether having a first-degree relative with dementia influenced older adults' self-reported memory, if personality traits moderated these associations, and whether these associations differed by the type of item asked (ie, frequency of memory problems vs perceived memory decline). Data drawn from the Einstein Aging study included 454 older adults (Mage = 76.64, standard deviation = 4.77, 66.96% white, and 63% female). Multilevel modeling analyses showed participants who had a first-degree relative with dementia reported more frequent memory problems and were more likely to report memory decline over the past year. Among participants with a first-degree relative with dementia, higher levels of neuroticism were related to reports of more frequent memory problems at baseline, whereas higher levels of conscientiousness and lower levels of extraversion were related to reports of more frequent memory problems over time. Future research should consider personality traits and family history of dementia as potential contributors to self-reported memory problems.

Interactive Effects of Racial Identity and Repetitive Head Impacts on Cognitive Function, Structural MRI-Derived Volumetric Measures, and Cerebrospinal Fluid Tau and Aβ

BACKGROUND

Factors of increased prevalence among individuals with Black racial identity (e.g., cardiovascular disease, CVD) may influence the association between exposure to repetitive head impacts (RHI) from American football and later-life neurological outcomes. Here, we tested the interaction between racial identity and RHI on neurobehavioral outcomes, brain volumetric measures, and cerebrospinal fluid (CSF) total tau (t-tau), phosphorylated tau (p-tau181), and Aβ1 - 42 in symptomatic former National Football League (NFL) players.

METHODS

68 symptomatic male former NFL players (ages 40-69; n = 27 Black, n = 41 White) underwent neuropsychological testing, structural MRI, and lumbar puncture. FreeSurfer derived estimated intracranial volume (eICV), gray matter volume (GMV), white matter volume (WMV), subcortical GMV, hippocampal volume, and white matter (WM) hypointensities. Multivariate generalized linear models examined the main effects of racial identity and its interaction with a cumulative head impact index (CHII) on all outcomes. Age, years of education, Wide Range Achievement Test, Fourth Edition (WRAT-4) scores, CVD risk factors, and APOEε4 were included as covariates; eICV was included for MRI models. P-values were false discovery rate adjusted.

RESULTS

Compared to White former NFL players, Black participants were 4 years younger (p = 0.04), had lower WRAT-4 scores (mean difference = 8.03, p = 0.002), and a higher BMI (mean difference = 3.09, p = 0.01) and systolic blood pressure (mean difference = 8.15, p = 0.03). With regards to group differences on the basis of racial identity, compared to White former NFL players, Black participants had lower GMV (mean adjusted difference = 45649.00, p = 0.001), lower right hippocampal volume (mean adjusted difference = 271.96, p = 0.02), and higher p-tau181/t-tau ratio (mean adjusted difference = -0.25, p = 0.01). There was not a statistically significant association between the CHII with GMV, right hippocampal volume, or p-tau181/t-tau ratio. However, there was a statistically significant Race x CHII interaction for GMV (b = 2206.29, p = 0.001), right hippocampal volume (b = 12.07, p = 0.04), and p-tau181/t-tau ratio concentrations (b = -0.01, p = 0.004).

CONCLUSION

Continued research on racial neurological disparities could provide insight into risk factors for long-term neurological disorders associated with American football play.

Racial disparities and temporal trends in dementia misdiagnosis risk in the United States

Introduction

Systematic disparities in misdiagnosis of dementia across racial/ethnic groups have implications for health disparities. We compared the risk of dementia under- and overdiagnosis in clinical settings across racial/ethnic groups from 2000 to 2010.

Methods

We linked fee-for-service Medicare claims to participants aged ≥70 from the nationally representative Health and Retirement Study. We classified dementia status using an algorithm with similar sensitivity and specificity across racial/ethnic groups and assigned clinical dementia diagnosis status using ICD-9-CM codes from Medicare claims. Multinomial logit models were used to estimate relative risks of clinical under- and overdiagnosis between groups and over time.

Results

Non-Hispanic blacks had roughly double the risk of underdiagnosis as non-Hispanic whites. While primary analyses suggested a shrinking disparity over time, this was not robust to sensitivity analyses or adjustment for covariates. Risk of overdiagnosis increased over time in both groups.

Discussion

Our results suggest that efforts to reduce racial disparities in underdiagnosis are warranted.

Differences in lipidome and metabolome organization of prefrontal cortex among human populations

Human populations, despite their overwhelming similarity, contain some distinct phenotypic, genetic, epigenetic, and gene expression features. In this study, we explore population differences at yet another level of molecular phenotype: the abundance of non-polar and polar low molecular weight compounds, lipids and metabolites in the prefrontal cortical region of the brain. We assessed the abundance of 1,670 lipids and 258 metabolites in 146 Han Chinese, 97 Western European, and 60 African American individuals of varying ages, covering most of the lifespan. The statistical analysis and logistic regression models both demonstrated extensive lipid and metabolic divergence of the Han Chinese individuals from the other two populations. This divergence was age-dependent, peaking in young adults, and involved metabolites and lipids clustering in specific metabolic pathways.

Disparities in Dementia Occurrence and Rate of Cognitive Decline Between African American and White Long-Term Care Residents

The objective of the current study was to investigate possible racial disparities in dementia among long-term care (LTC) residents. Participants were 1,239 residents (age ≥50) from 61 nursing home and assisted living facilities in Maryland. Retrospective analysis was performed to compare Brief Cognitive Assessment Tool (BCAT®) scores between African American and White participants. African American participants had 1.43 times greater odds of dementia and 1.86 times greater odds of severe-stage dementia than White residents. African American residents were significantly younger than their White peers by approximately 9 years within mild-moderate dementia levels and by 5 years at the severe stage. The rate of cognitive decline did not significantly differ by race despite a more negative curvilinear relationship between BCAT scores and age for African American participants than White participants. Implications of these findings are discussed for successful resident-centered care in LTC settings as well as for care transitions. [Research in Gerontological Nursing, xx(x), xx-xx.].

A mixed-methods study of cultural beliefs about dementia and genetic testing among Mexicans and Mexican-Americans at-risk for autosomal dominant Alzheimer's disease

Trials to prevent autosomal dominantly inherited Alzheimer's disease (ADAD) are critical and timely. However, cultural beliefs about AD and genetic testing may preclude informed consent and participation, especially among racial/ethnic minorities. This mixed-methods study examines cultural beliefs about AD and genetic screening among at-risk populations of Mexican heritage. We surveyed 86 Mexican and 37 Mexican-American family members of patients with ADAD and interviewed 18 respondents in Mexico to explore perceptions and knowledge regarding AD and genetic testing. While most respondents understood that AD is inherited in their families, they also had limited understanding of the genetic mechanisms behind AD. Many believed that AD is a normal part of aging or that it is a mental illness caused by bad habits. However, beliefs that AD is caused by a curse or God's will were uncommon. The interviews demonstrated that very few at-risk respondents understood their own risk for harboring the mutation causing AD in their family. Once informed, most expressed a strong interest in genetic testing, largely motivated by the desire to be better prepared for the development of AD. Health professionals treating and investigators enrolling members from families with ADAD cannot assume that they fully understand the nature of the illness; therefore, providers should provide comprehensive information about ADAD and genetic testing.

Discriminative Ability of Montreal Cognitive Assessment Subtests and Items in Racial and Ethnic Minority Groups

INTRODUCTION

The Montreal Cognitive Assessment (MoCA) is a popular screening tool for Mild Cognitive Impairment (MCI). The psychometric properties of the MoCA have not been widely examined in minority groups. We aimed to analyze the discriminate ability of subtests and items by race and ethnicity given gold-standard clinical diagnosis of cognitive status.

METHODS

We analyzed data from the National Alzheimer Coordinating Center Uniform Data Set March 2018 data freeze. Stepwise regression was used to determine which subtests predicted cognitive status (normal cognition, MCI, or dementia), by race/ethnicity. Item discrimination and difficulty was calculated by race/ethnicity and cognitive status.

RESULTS

In our sample (n=3895), with an average age of 69.7, 80.7% were non-Hispanic white, 15.0% were non-Hispanic black, and 4.2% were Hispanic. Among non-Hispanic whites all subtests, education, and age predicted clinician diagnosis, while visuospatial/executive, attention, language, delayed recall, and orientation subtests were predictive among non-Hispanic blacks and visuospatial/executive, delayed recall, and orientation subtests and education were predictive among Hispanics. Item discrimination and difficulty varied by race/ethnicity and cognitive status.

CONCLUSIONS

By understanding the psychometric properties of MoCA subtests, we can focus on subtests that have higher discrimination and more diagnostic utility. Subtests should be further evaluated for use in screening of minority individuals.

Childhood Lead Exposure and Adult Neurodegenerative Disease

Millions of Americans now entering midlife and old age were exposed to high levels of lead, a neurotoxin, as children. Evidence from animal-model and human observational studies suggest that childhood lead exposure may raise the risk of adult neurodegenerative disease, particularly dementia, through a variety of possible mechanisms including epigenetic modification, delayed cardiovascular and kidney disease, direct degenerative CNS injury from lead remobilized from bone, and lowered neural and cognitive reserve. Within the next ten years, the generation of children with the highest historical lead exposures, those born in the 1960s, 1970s, and 1980s, will begin to enter the age at which dementia symptoms tend to emerge. Many will also enter the age in which lead stored in the skeleton may be remobilized at greater rates, particularly for women entering menopause and men and women experiencing osteoporosis. Should childhood lead exposure prove pro-degenerative, the next twenty years will provide the last opportunities for possible early intervention to forestall greater degenerative disease burden across the aging lead-exposed population. More evidence is needed now to characterize the nature and magnitude of the degenerative risks facing adults exposed to lead as children and to identify interventions to limit long-term harm.

Dementia-Related Neuropsychological Testing Considerations in Non-Hispanic White and Latino/Hispanic Populations

Hispanic individuals are at greater risk for health disparities, less than optimal health care, and are diagnosed at later stages of cognitive impairment than white non-Hispanics. Acculturation and different attitudes toward test-taking may result in decrements in performance, especially on unfamiliar measures that emphasize speed and accuracy. Non-Hispanic individuals often outperform Hispanic individuals on cognitive and neuropsychological measures in community and clinical populations. Current neuropsychological testing may not provide accurate data related to monolingual and bilingual individuals of Hispanic descent. Testing instruments were identified by searching academic databases using combinations of relevant search terms. Neuropsychological instruments were included if they were designed to detect cognitive impairment, had an administration time of less than 45 minutes, and were available in English. Validity studies were required to employ gold standard comparison diagnostic criteria. Twenty-nine instruments were evaluated in dementia staging, global cognition, memory, memory and visual abilities, working memory and attention, verbal learning and memory, recall, language, premorbid intelligence, literacy/cognitive reserve, visuospatial, attention, problem-solving, problem solving and perception, functional assessment, and mood/daily functioning domains. Spanish-language neuropsychological instruments need to be made widely available and existing instruments to be normed in Spanish to best serve and assess diverse populations. Psychometric data were reported for neuropsychological instruments, which may be administered to Hispanic older adults presenting for evaluation related to dementia-spectrum disorders. This is one of the few reviews to provide an overview of the sensitivity and specificity of available Spanish translated neuropsychological instruments.

Cerebral Amyloid Angiopathy: Similarity in African-Americans and Caucasians with Alzheimer's Disease

Cerebral amyloid angiopathy (CAA) of the Aβ type is variably present in the brains of patients with Alzheimer's disease (AD). CAA contributes to cognitive decline and increases the risk of lobar hemorrhage; because both AD-typical dementia and lobar hemorrhage are more common in African-Americans than in Caucasians, we postulated that African-Americans with AD might be particularly susceptible to CAA. To test this hypothesis, we analyzed CAA histopathologically in the large vessels and capillaries of autopsy-derived frontal, temporal, parietal, and occipital cortical samples from African-Americans (n = 18) and Caucasians (n = 19) with end-stage AD. In the combined cohort of 37 subjects, 22% of the subjects had severe CAA in large vessels, and 11% had severe CAA in capillaries. However, the prevalence and histopathologic characteristics of CAA were similar in the African-Americans and Caucasians. This conclusion was substantiated in an independent sample from the National Alzheimer's Coordinating Center database, in which the degree of CAA was comparable in 1,554 Caucasians and 68 African-Americans with end-stage AD. These findings support a growing consensus that the fundamental histopathologic features of AD are largely impartial to the race of the afflicted.

Cardiovascular disease risk factor burden and cognition: Implications of ethnic diversity within the Hispanic Community Health Study/Study of Latinos

OBJECTIVE

Hispanics/Latinos have some of the highest prevalence rates for cardiovascular disease risk factors, but stark differences exist by self-reported background. Cardiovascular disease risk factors negatively impact cognition in Hispanics/Latinos; less is known about these relationships by Hispanic/Latino backgrounds. We investigated cognitive associations with cardiovascular disease risk factor burden in a diverse cohort, the Hispanic Community Health Study/Study of Latinos.

METHODS

Baseline data from this observational study of cardiovascular disease and its antecedents was collected from 2008-2011. We included 7,121 participants 45-74 years old from Central American, Cuban, Dominican, Mexican, Puerto Rican, or South American backgrounds. Dichotomous indicators for hypertension, diabetes, hypercholesterolemia, obesity, and smoking were evaluated and totaled, with participants grouped by lowest (0-2), middle (3) or highest (4-5) burden. Cognitive testing included the Brief Spanish English Verbal Learning Test, letter fluency, and digit symbol substitution.

RESULTS

In separate fully-adjusted linear regression models, lower fluency and digit symbol substitution performance were restricted to the highest compared to the lowest burden group; whereas the middle burden group displayed impaired memory performance compared to the lowest burden group (p-values≤0.05). Background interacted with burden for learning and memory performance. That is, the association of burden level (i.e., lowest, middle, or highest) with cognitive performance was modified by background (e.g., Mexicans vs Cuban).

CONCLUSIONS

Hispanics/Latinos with higher levels of cardiovascular disease risk factor burden displayed lower levels of cognitive performance, with learning and memory performance modified by background.

Quantifying the Diagnostic Pathway for Patients with Cognitive Impairment: Real-World Data from Seven European and North American Countries

To ensure that patients with dementia and their caregivers receive appropriate treatment and support, early diagnosis is essential but remains challenging. Real-world data from a multi-national, cross-sectional survey of physicians and their patients were analyzed to quantify the diagnostic pathway for dementia, including a focus on severity of patients' cognitive impairment (CI) at the time of symptom onset, referral and subsequent diagnosis. Data were collected for 7,620 patients with CI. Most patients saw a healthcare professional within 1 year of first symptoms and received a diagnosis within 3-7 months of initial consultation. However, only 20% of patients received a diagnosis before their disease progressed beyond the prodromal stage and 23.5% already had moderate CI at diagnosis. These findings show that the goal of identifying and diagnosing CI at the earliest stages of disease is, for many patients, not achieved. Efforts toward public awareness and proactive, earlier detection and intervention, must be maintained-indeed where possible invigorated.

Cognitive Training for Ethnic Minority Older Adults in the United States: A Review

Purpose of the Study

Interest in cognitive training for healthy older adults to reduce cognitive decline has grown considerably over the past few decades. Given the shift toward a more diverse society, the purpose of this review is to examine the extent of race/ethnic minority participation in cognitive training studies and characteristics of studies that included race/ethnic minority participants.

Design and Methods

This review considered peer-reviewed studies reporting cognitive training studies for cognitively healthy, community-dwelling older adults (age 55+) in the United States published in English before December 31, 2015. A total of 31 articles published between 1986 and 2015 meeting inclusion criteria were identified and included in the review.

Results

A total of 6,432 participants were recruited across all of the studies, and ranged in age from 55 to 99 years. Across all studies examined, 39% reported racial/ethnic background information. Only 3 of these studies included a substantial number of minorities (26.7% in the ACTIVE study; 28.4% in the SeniorWISE study; 22.7% in the TEAM study). Race/ethnic minority older adults were disproportionately underrepresented in cognitive training studies.

Implications

Further research should aim to enroll participants representative of various race/ethnic minority populations. Strategies for recruitment and retention of ethnic minority participants in cognitive training research are discussed, which could lead to the development of more culturally appropriate and perhaps more effective cognitive interventions.