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To generalize findings on the mechanisms and prognosis in Alzheimer's disease and related dementias (ADRD), it is critical for ADRD research to be representative of the population. Sociodemographic and health characteristics across ethnoracial groups included in the National Alzheimer's Coordinating Center sample (NACC) were compared to the nationally representative Health and Retirement Study (HRS).Baseline NACC data (n = 36,639) and the weighted 2010 HRS wave (N = 52,071,840) were included. We assessed covariate balance by calculating standardized mean differences across harmonized covariates (i.e., sociodemographic, health).NACC participants were older, more educated, with worse subjective memory and hearing, but endorsed fewer depressive symptoms compared to HRS participants. While all racial and ethnic groups in NACC differed from HRS participants in the same way overall, these differences were further amplified between racial and ethnic groups.NACC participants do not represent the U.S. population in key demographic and health factors, which differed by race and ethnicity.HighlightsWe examined selection factors included in NACC studies compared to a nationally representative sample.Selection factors included demographic and health factors and self-reported memory concerns.Results suggest that NACC participants are not representative of the U.S. population.Importantly, selection factors differed across racial and ethnic groups.Findings are suggestive of selection bias within NACC studies.

IntroductionMethodResultsConclusionsThe field of neuropsychology is undergoing notable changes, especially in the context of the Minnesota Update Conference (MNC) guidelines draft development. In late 2023, a group of neuropsychology trainee-leaders, united through the Clinical Neuropsychology Trainee Forum (CNTF), surveyed neuropsychology trainees in the United States and Canada to better understand their needs and their perception of the current training climate.Survey items were drafted by a CNTF task force consisting of trainee-leaders from major neuropsychology organizations before being refined by four independent neuropsychologists. The survey was distributed via listservs and social media. Survey results were analyzed using frequency descriptives and analyses of variance to compare differences in responses based on demographic and training-related factors.Respondents who completed a majority of the survey (n = 220) were primarily female (86%), White (71%), and training in the United States (92%). More than 75% of respondents reported satisfaction with their doctoral program, internship, and/or fellowship. Similarly, 90% and 73% of the respondents, respectively, felt their opinions on the future of the field listened to and/or valued in discussions with peers and supervisors/mentors. However, only 57% of the respondents felt their opinions were valued by neuropsychology organizational leadership, and approximately 30% of the respondents agreed that trainees’ opinions were valued during the MNC draft development review period. Another 40% of the respondents were uncertain about trainee perspectives being valued during the MNC process.Most neuropsychology trainees are satisfied with their training, yet they expressed concerns about their opinions on the future of the field being heard by neuropsychology leadership. Trainee stakeholder engagement will be important to the vitality of neuropsychology in light of anticipated MNC Guidelines. Recommendations for the field of neuropsychology to support trainees will be discussed. [ABSTRACT FROM AUTHOR]

Objectives: Examine whether physical activity (PA) changes during the COVID-19 pandemic were related to subjective cognitive decline (SCD), depression, and anxiety in older adults and whether these varied by sociodemographic variables. Methods: 301 older adults completed an online survey between May and October 2020 and 3 months later, including self-report questionnaires of SCD, depression, and anxiety. PA changes were determined with a question. Results: 60% of participants reported decreased PA. Those who reduced their PA were more likely to be from low to middle income and younger. PA increase was related to less SCD and depressive symptoms compared to those who decreased it. Participants who maintained their PA had fewer SCD concerns, depressive, and anxiety symptoms than those who decreased it. Discussion: Reducing PA was associated with worse neuropsychiatric and cognitive symptoms. Encouraging older adults to increase PA may help mitigate some of the pandemic's adverse effects on psychological well-being. [ABSTRACT FROM AUTHOR]

Background: Patient‐centered care for persons with Parkinson's disease (PwPD) is associated with positive outcomes, but is lacking in current healthcare systems. Objective: In this qualitative study, we solicited advice from PwPD to medical professionals, family members/friends, and newly‐diagnosed PwPD. Methods: Through an online survey, 275 PwPD answered open‐ended questions asking for their advice. Responses were analyzed using content analysis. Interrater reliability was 94.5%. Results: Three qualitative themes were identified. First, participants advised enhancing care and communication, with healthcare professionals balancing clinical constraints with compassion, and family/friends balancing support with appreciating autonomy of PwPD. The second theme was empowering PwPD through increasing their knowledge of the disease and care options. The third reflected the importance of focusing on well‐being and connection. Conclusion: The results highlight several gaps in meeting the needs of PwPD in healthcare settings and personal relationships, underscoring the importance of integrating their perspectives in shaping approaches to care. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Depressive symptoms are among early behavioral changes in Alzheimer's disease (AD); however, the relationship between neurodegeneration and depressive symptoms remains inconclusive. To better understand this relationship in preclinical AD, we examined hippocampal volume and depressive symptoms in cognitively unimpaired carriers of the presenilin‐1 (PSEN1) E280A mutation for autosomal dominant AD. METHODS: A total of 27 PSEN1 mutation carriers and 26 non‐carrier family members were included. Linear regression was used to test the relationship between hippocampal volume and 15‐item Geriatric Depression Scale. RESULTS: Carriers and non‐carriers did not differ in depressive symptoms or hippocampal volume. Within carriers, lower hippocampal volume was associated with greater depressive symptoms, which remained significant after adjusting for age and cognition. This relationship was not significant in non‐carriers. DISCUSSION: Hippocampal neurodegeneration may underlie depressive symptoms in preclinical autosomal dominant AD. These findings provide support for the utility of targeting depressive symptoms in AD prevention. Highlights: We compared unimpaired autosomal dominant Alzheimer's disease (AD) mutation carriers and non‐carriers.Carriers and non‐carriers did not differ in severity of depressive symptoms.In carriers, hippocampal volume was inversely associated with depressive symptoms.Depressive symptoms may be a useful target in AD prevention. [ABSTRACT FROM AUTHOR]

Objectives: Alzheimer's disease (AD) is known to impact semantic access, which is frequently evaluated using the Category Fluency (Animals) test. Recent studies have suggested that in addition to overall category fluency scores (total number of words produced over time), poor clustering could signal AD-related cognitive difficulties. In this study, we examined the association between category fluency clustering performance (i.e., stating words sequentially that are all contained within a subcategory, such as domestic animals) and brain pathology in individuals with autosomal dominant Alzheimer's disease (ADAD). Methods: A total of 29 non-demented carriers of the Presenilin1 E280A ADAD mutation and 32 noncarrier family members completed the category fluency test (Animals) and the Mini-Mental State Examination (MMSE). The participants also underwent positron emission tomography (PET) scans to evaluate in vivo amyloid-beta in the neocortex and tau in medial temporal lobe regions. Differences between carriers and noncarriers on cognitive tests were assessed with Mann-Whitney tests; associations between cognitive test performance and brain pathology were assessed with Spearman correlations. Results: Animal fluency scores did not differ between carriers and noncarriers. Carriers, however, showed a stronger association between animal fluency clustering and in vivo AD brain pathology (neocortical amyloid and entorhinal tau) relative to noncarriers. Conclusion: This study indicates that using category fluency clustering, but not total score, is related to AD pathophysiology in the preclinical and early stages of the disease. [ABSTRACT FROM AUTHOR]

Background: The computerized NIH Toolbox Cognition Battery (NIHTB‐CB) was designed to assess cognitive functioning across the lifespan. Previous studies demonstrated that NIHTB‐CB measures discriminate between healthy controls (HCs), individuals with amnestic mild cognitive impairment (aMCI), and individuals with dementia of the Alzheimer's type (DAT). Scores on NIHTB‐CB tasks also correspond with performance on well‐validated neuropsychological measures of the same cognitive domains. We are among the first to evaluate how NIHTB‐CB subtest performances and in vivo Alzheimer's disease (AD) pathology are related in people with aMCI and DAT. Method: As part of a larger clinical trial in the Research Program on Cognition and Neuromodulation Based Interventions, 139 participants with aMCI or DAT (Table 1) underwent neuropsychological assessment, including five iPad NIHTB‐CB subtests: Flanker, List Sort, Card Sort, Pattern Separation, and Picture Sequence. Participants also completed positron emission tomography (PET) scans of amyloid and tau. Amyloid PET scans were normalized to the centiloid value, and tau PET standardized uptake value ratios (SUVr) were merged into a bilateral meta‐region‐of‐interest based on Braak staging. Stepwise linear regressions were used to evaluate the relationship between age and education with NIHTB‐CB subtests (Model 1), as well as in vivo AD pathophysiology with NIHTB‐CB subtests beyond age and education (Model 2). Result: In vivo amyloid was significantly related to List Sort (β = ‐0.31, p<.001, ΔR2 =.09) and Card Sort performance (β = ‐0.25, p =.004, ΔR2 =.06), explaining significantly more subtest variance beyond age and education. In vivo tau was significantly related to performance on all NIHTB‐CB subtests and explained significantly more subtest variance than demographic factors (Flanker: β = ‐0.25, p =.004, ΔR2 =.06; List Sort: β = ‐0.40, p<.001, ΔR2 =.15; Card Sort: β = ‐0.32, p<.001, ΔR2 =.10; Pattern Separation: β = ‐0.18, p =.04, ΔR2 =.03; Picture Sequence: β = ‐0.23, p =.01, ΔR2 =.05). Conclusion: In vivo AD pathophysiology is related to NIHTB‐CB subtest performances in individuals with aMCI or DAT and explains significantly more NIHTB‐CB subtest variance than demographic factors alone. This work adds growing support to the relationship between NIHTB‐CB subtests and in vivo AD biomarkers. [ABSTRACT FROM AUTHOR]

Introduction: Plasma‐measured tau phosphorylated at threonine 217 (p‐tau217) is a potential non‐invasive biomarker of Alzheimer's disease (AD). We investigated whether plasma p‐tau217 predicts subsequent cognition and positron emission tomography (PET) markers of pathology in autosomal dominant AD. Methods: We analyzed baseline levels of plasma p‐tau217 and its associations with amyloid PET, tau PET, and word list delayed recall measured 7.61 years later in non‐demented age‐ and education‐matched presenilin‐1 E280A carriers (n = 24) and non‐carrier (n = 20) family members. Results: Carriers had higher plasma p‐tau217 levels than non‐carriers. Baseline plasma p‐tau217 was associated with subsequent amyloid and tau PET pathology levels and cognitive function. Discussion: Our findings suggest that plasma p‐tau217 predicts subsequent brain pathological burden and memory performance in presenilin‐1 E280A carriers. These results provide support for plasma p‐tau217 as a minimally invasive diagnostic and prognostic biomarker for AD, with potential utility in clinical practice and trials. Highlights: Non‐demented presenilin‐1 E280A carriers have higher plasma tau phosphorylated at threonine 217 (p‐tau217) than do age‐matched non‐carriers.Higher baseline p‐tau217 is associated with greater future amyloid positron emission tomography (PET) pathology burden.Higher baseline p‐tau217 is associated with greater future tau PET pathology burden.Higher baseline p‐tau217 is associated with worse future memory performance. [ABSTRACT FROM AUTHOR]

Prior teleneuropsychological research has assessed the reliability between in-person and remote administration of cognitive assessments. Few, if any, studies have examined the test-retest reliability of cognitive assessments conducted in sequential clinic-to-home or home-to-home teleneuropsychological evaluations – a critical issue given the state of clinical practice during the COVID-19 pandemic. This study examined this key psychometric question for several cognitive tests administered over repeated videoconferencing visits 4-6 months apart in a sample of healthy English-speaking adults. A total of 44 participants (ages 18-75) completed baseline and follow-up cognitive testing 4-6 months apart. Testing was conducted in a home-to-home setting over HIPAA-compliant videoconferencing meetings on participants' audio-visual enabled laptop or desktop computers. The following measures were repeated at both virtual visits: the Controlled Oral Word Association Test (FAS), Category Fluency (Animals), and Digit Span Forward and Backward from the Wechsler Adult Intelligence Scale, Fourth Edition. Intraclass correlation coefficients (ICC), Pearson correlations, root mean square difference (RMSD), and concordance correlation coefficients (CCC) were calculated as test-retest reliability metrics, and practice effects were assessed using paired-samples t-tests. Some tests exhibited small practice effects, and test-retest reliability was marginal or worse for all measures except FAS, which had adequate reliability (based on ICC and r). Reliability estimates with RMSD suggested that change within +/- 1 SD on these measures may reflect typical test-retest variability. The included cognitive measures exhibited questionable reliability over repeated home-to-home videoconferencing evaluations. Future teleneuropsychology test-retest reliability research is needed with larger, more diverse samples and in clinical populations. [ABSTRACT FROM AUTHOR]

Background: Olfactory dysfunction is one of the earliest signs of Alzheimer's disease (AD), highlighting its potential use as a biomarker for early detection. It has also been linked to progression from mild cognitive impairment (MCI) to dementia.Objective: To study olfactory function and its associations with markers of AD brain pathology in non-demented mutation carriers of an autosomal dominant AD (ADAD) mutation and non-carrier family members.Methods: We analyzed cross-sectional data from 16 non-demented carriers of the Presenilin1 E280A ADAD mutation (mean age [SD]: 40.1 [5.3], and 19 non-carrier family members (mean age [SD]: 36.0 [5.5]) from Colombia, who completed olfactory and cognitive testing and underwent amyloid and tau positron emission tomography (PET) imaging.Results: Worse olfactory identification performance was associated with greater age in mutation carriers (r = -0.52 p = 0.037). In carriers, worse olfactory identification performance was related to worse MMSE scores (r = 0.55, p = 0.024) and CERAD delayed recall (r = 0.63, p = 0.007) and greater cortical amyloid-β (r = -0.53, p = 0.042) and tau pathology burden (entorhinal: r = -0.59, p = 0.016; inferior temporal: r = -0.52, p = 0.038).Conclusion: Worse performance on olfactory identification tasks was associated with greater age, a proxy for disease progression in this genetically vulnerable ADAD cohort. In addition, this is the first study to report olfactory dysfunction in ADAD mutation carriers with diagnosis of MCI and its correlation with abnormal accumulation of tau pathology in the entorhinal region. Taken together, our findings suggest that olfactory dysfunction has promise as an early marker of brain pathology and future risk for dementia. [ABSTRACT FROM AUTHOR]