APOE3 Christchurch modulates ß-catenin/Wnt signaling in iPS cell-derived cerebral organoids from Alzheimer's cases.

A patient with the PSEN1 E280A mutation and homozygous for APOE3 Christchurch (APOE3Ch) displayed extreme resistance to Alzheimer's disease (AD) cognitive decline and tauopathy, despite having a high amyloid burden. To further investigate the differences in biological processes attributed to APOE3Ch, we generated induced pluripotent stem (iPS) cell-derived cerebral organoids from this resistant case and a non-protected control, using CRISPR/Cas9 gene editing to modulate APOE3Ch expression. In the APOE3Ch cerebral organoids, we observed a protective pattern from early tau phosphorylation. ScRNA sequencing revealed regulation of Cadherin and Wnt signaling pathways by APOE3Ch, with immunostaining indicating elevated ß-catenin protein levels. Further in vitro reporter assays unexpectedly demonstrated that ApoE3Ch functions as a Wnt3a signaling enhancer. This work uncovered a neomorphic molecular mechanism of protection of ApoE3 Christchurch, which may serve as the foundation for the future development of protected case-inspired therapeutics targeting AD and tauopathies.

Study Partner Report of Apathy in Older Adults is Associated with AD Biomarkers: Findings from the Harvard Aging Brain Study.

OBJECTIVES: We examined relationships between apathy (self and study-partner-reported) and markers of Alzheimer's disease (AD) in older adults. DESIGN: The study utilized a well-characterized sample of participants from the Harvard Aging Brain Study (HABS), a longitudinal cohort study. Participants were cognitively unimpaired without clinically significant neuropsychiatric symptoms at HABS baseline. The dependent variables, apathy evaluation scale-self (AES-S) and informant (AES-I), were administered cross-sectionally between years 6-9 and compared to the independent variables, amyloid and tau PET neuroimaging, from the same year. SETTING: Community-dwelling participants assessed at research visits in an academic medical center. PARTICIPANTS: Participants (n = 170) completed assessments within 1.5 years of their neuroimaging visit. At the time of apathy assessment, N = 156 were cognitively unimpaired and 14 had progressed to mild cognitive impairment (n = 8) or dementia (n = 6). MEASUREMENTS: We utilized linear regression models to assess cross-sectional associations of AES-S and AES-I with AD PET imaging measures (beta-amyloid (Pittsburgh Compound B) and tau (Flortaucipir)), covarying for age, sex, education, and the time between PET scan-apathy assessment. RESULTS: AES-I was significantly associated with beta-amyloid and temporal lobe tau, and the associations were retained after further adjusting for depressive symptoms. The associations between AES-S and AD biomarkers were not significant. In an exploratory subgroup analysis of cognitively unimpaired individuals with elevated Aß, we observed an association between AES-I and inferior temporal tau. CONCLUSIONS: Study-partner-reported, but not self-reported, apathy in older adults is associated with AD pathology, and we observed this relationship starting from the preclinical stage. Our findings highlight the importance of collateral information in capturing AD-related apathy.

Novel avenues of tau research.

INTRODUCTION: The pace of innovation has accelerated in virtually every area of tau research in just the past few years. METHODS: In February 2022, leading international tau experts convened to share selected highlights of this work during Tau 2022, the second international tau conference co-organized and co-sponsored by the Alzheimer's Association, CurePSP, and the Rainwater Charitable Foundation. RESULTS: Representing academia, industry, and the philanthropic sector, presenters joined more than 1700 registered attendees from 59 countries, spanning six continents, to share recent advances and exciting new directions in tau research. DISCUSSION: The virtual meeting provided an opportunity to foster cross-sector collaboration and partnerships as well as a forum for updating colleagues on research-advancing tools and programs that are steadily moving the field forward.

Associations of category fluency clustering performance with in vivo brain pathology in autosomal dominant Alzheimer's disease.

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.

Depressive symptoms and hippocampal volume in autosomal dominant Alzheimer's disease.

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.

APOE Christchurch-mimetic therapeutic antibody reduces APOE-mediated toxicity and tau phosphorylation.

INTRODUCTION: We discovered that the APOE3 Christchurch (APOE3Ch) variant may provide resistance to Alzheimer's disease (AD). This resistance may be due to reduced pathological interactions between ApoE3Ch and heparan sulfate proteoglycans (HSPGs). METHODS: We developed and characterized the binding, structure, and preclinical efficacy of novel antibodies targeting human ApoE-HSPG interactions. RESULTS: We found that one of these antibodies, called 7C11, preferentially bound ApoE4, a major risk factor for sporadic AD, and disrupts heparin-ApoE4 interactions. We also determined the crystal structure of a Fab fragment of 7C11 and used computer modeling to predict how it would bind to ApoE. When we tested 7C11 in mouse models, we found that it reduced recombinant ApoE-induced tau pathology in the retina of MAPT*P301S mice and curbed pTau S396 phosphorylation in brains of systemically treated APOE4 knock-in mice. Targeting ApoE-HSPG interactions using 7C11 antibody may be a promising approach to developing new therapies for AD.

Association of Pathologic and Volumetric Biomarker Changes With Cognitive Decline in Clinically Normal Adults.

BACKGROUND AND OBJECTIVES: Hippocampal volume (HV) atrophy is a well-known biomarker of memory impairment. However, compared with ß-amyloid (Aß) and tau imaging, it is less specific for Alzheimer disease (AD) pathology. This lack of specificity could provide indirect information about potential copathologies that cannot be observed in vivo. In this prospective cohort study, we aimed to assess the associations among Aß, tau, HV, and cognition, measured over a 10-year follow-up period with a special focus on the contributions of HV atrophy to cognition after adjusting for Aß and tau. METHODS: We enrolled 283 older adults without dementia or overt cognitive impairment in the Harvard Aging Brain Study. In this report, we only analyzed data from individuals with available longitudinal imaging and cognition data. Serial MRI (follow-up duration 1.3-7.0 years), neocortical Aß imaging on Pittsburgh Compound B PET scans (1.9-8.5 years), entorhinal and inferior temporal tau on flortaucipir PET scans (0.8-6.0 years), and the Preclinical Alzheimer Cognitive Composite (3.0-9.8 years) were prospectively collected. We evaluated the longitudinal associations between Aß, tau, volume, and cognition data and investigated sequential models to test the contribution of each biomarker to cognitive decline. RESULTS: We analyzed data from 128 clinically normal older adults, including 72 (56%) women and 56 (44%) men; median age at inclusion was 73 years (range 63-87). Thirty-four participants (27%) exhibited an initial high-Aß burden on PET imaging. Faster HV atrophy was correlated with faster cognitive decline (R2 = 0.28, p < 0.0001). When comparing all biomarkers, HV slope was associated with cognitive decline independently of Aß and tau measures, uniquely accounting for 10% of the variance. Altogether, 45% of the variance in cognitive decline was explained by combining the change measures in the different imaging biomarkers. DISCUSSION: In older adults, longitudinal hippocampal atrophy is associated with cognitive decline, independently of Aß or tau, suggesting that non-AD pathologies (e.g., TDP-43, vascular) may contribute to hippocampal-mediated cognitive decline. Serial HV measures, in addition to AD-specific biomarkers, may help evaluate the contribution of non-AD pathologies that cannot be measured otherwise in vivo.

The APOE-R136S mutation protects against APOE4-driven Tau pathology, neurodegeneration and neuroinflammation.

Apolipoprotein E4 (APOE4) is the strongest genetic risk factor for late-onset Alzheimer's disease (LOAD), leading to earlier age of clinical onset and exacerbating pathologies. There is a critical need to identify protective targets. Recently, a rare APOE variant, APOE3-R136S (Christchurch), was found to protect against early-onset AD in a PSEN1-E280A carrier. In this study, we sought to determine if the R136S mutation also protects against APOE4-driven effects in LOAD. We generated tauopathy mouse and human iPSC-derived neuron models carrying human APOE4 with the homozygous or heterozygous R136S mutation. We found that the homozygous R136S mutation rescued APOE4-driven Tau pathology, neurodegeneration and neuroinflammation. The heterozygous R136S mutation partially protected against APOE4-driven neurodegeneration and neuroinflammation but not Tau pathology. Single-nucleus RNA sequencing revealed that the APOE4-R136S mutation increased disease-protective and diminished disease-associated cell populations in a gene dose-dependent manner. Thus, the APOE-R136S mutation protects against APOE4-driven AD pathologies, providing a target for therapeutic development against AD.

Cross-cultural adaptation of the everyday cognition scale (M-ECog) in older Mexican adults with cognitive impairment.

The Everyday Cognition (ECog) scale was created to evaluate the functional abilities of older adults across a wide range of abilities between normal aging and dementia. ECog screens cognitive alterations such as subjective cognitive decline (SCD) and mild cognitive impairment (MCI). This early recognition is done by the measurement of the ability to perform the activities of daily living (ADLs). Objective: To establish the cross-cultural adaptation, validity, and reliability of the ECog Mexican version (M-ECog) in participants with: SCD, MCI, and dementia coming from a memory clinic. Methods: There were 200 patients and their respective informants in a memory clinic of a third level hospital in Mexico City. Four groups were studied: 50 cognitively healthy (CH), 50 SCD, 50 MCI, and 50 dementia. The clinical evaluation included: sociodemographic and health characteristics, cognitive status by the Mini-Mental State Evaluation (MMSE) and Montreal Cognitive Evaluation Spanish version (MoCA-E), and caregiver information (informants) about the difficulty in ADLs as well as the ECog Spanish version (M-ECog). Results: The M-ECog was significantly correlated with MMSE, MoCA-E, and ADLs. It showed the ability to discriminate the different cognitive declines (Cronbach's alpha 0.881). The intra-class correlation coefficient was 0.877 (95% confidence interval - CI, 0.850-0.902; p<0.001). The patient's group area under curve (AUC) of M-ECog for SCD was 0.70 (95%CI 0.58-0.82, p<0.005), for MCI it was 0.94 (95%CI 0.89-0.99, p<0.001) and for dementia 0.86 (95%CI 0.79-0.92, p<0.001). Conclusion: The M-ECog scale proves to be valid and reliable for measuring everyday abilities mediated by cognition. It is self-applicable without requiring extensive prior formation. It is useful to screen for SCD and MCI in older Mexican adults.

A escala Cognição Cotidiana (ECog) foi criada para avaliar as habilidades funcionais de idosos em uma ampla gama de habilidades entre o envelhecimento normal e a demência. O ECog rastreia alterações cognitivas como declínio cognitivo subjetivo (DCS) e comprometimento cognitivo leve (CCL). Esse reconhecimento precoce é feito pela mensuração da capacidade de realizar as atividades de vida diária (AVD). Objetivo: Estabelecer a adaptação transcultural, validade e confiabilidade da versão mexicana do ECog (M-ECog) em participantes com: SCD, MCI e demência provenientes de uma clínica de memória. Métodos: Foram 200 pacientes e seus respectivos informantes em uma clínica de memória de um hospital de terceiro nível na Cidade do México. Quatro grupos foram estudados: 50 cognitivamente saudáveis (CH), 50 SCD, 50 MCI e 50 com demência. A avaliação clínica incluiu: características sociodemográficas e de saúde, estado cognitivo pelo Mini-Mental State Evaluation (MMSE) e Montreal Cognitive Evaluation versão em espanhol (MoCA-E), bem como informações do cuidador (informantes) sobre a dificuldade nas AVD e o ECog versão em espanhol (M-ECog). Resultados: O M-ECog foi significativamente correlacionado com MMSE, MoCA-E e AVD. Mostrou capacidade de discriminar os diferentes declínios cognitivos (alfa de Cronbach 0,881). O coeficiente de correlação intraclasse foi de 0,877 (intervalo de confiança de 95% ­ IC95%, 0,850­0,902; p<0,001). A AUC do grupo do paciente de M-ECog para SCD foi de 0,70 (IC95% 0,58­0,82, p<0,005), para MCI foi de 0,94 (IC95% 0,89­0,99, p<0,001) e para demência foi de 0,86 (IC95% 0,79­0,92, p<0,001). Conclusão: A escala M-ECog mostra-se válida e confiável para medir habilidades cotidianas mediadas pela cognição. É autoaplicável sem exigir extensa formação prévia. É útil para rastrear MSC e MCI em adultos mexicanos mais velhos.

Addressing the Chronic Pain-Early Cognitive Decline Comorbidity Among Older Adults: Protocol for the Active Brains Remote Efficacy Trial.

BACKGROUND: Chronic pain and early cognitive decline, which are costly to treat and highly prevalent among older adults, commonly co-occur, exacerbate one another over time, and can accelerate the development and progression of Alzheimer disease and related dementias. We developed the first mind-body activity program (Active Brains [AB]) tailored to the needs of older adults with chronic pain and early cognitive decline. Results from our previous study strongly supported the feasibility of conducting AB remotely and provided evidence for improvements in outcomes. OBJECTIVE: We are conducting a single-blinded, National Institutes of Health stage-2, randomized clinical trial to establish the efficacy of AB versus a time-matched and dose-matched education control (Health Enhancement Program [HEP]) in improving self-reported and objective outcomes of physical, cognitive, and emotional functions in 260 participants. The methodology described in this paper was informed by the lessons learned from the first year of the trial. METHODS: Participants are identified and recruited through multidisciplinary clinician-referred individuals (eg, pain psychologists and geriatricians), the Rally Research platform, social media, and community partnerships. Interested participants complete eligibility screening and electronic informed consent. Baseline assessments include self-report, performance-based measures (eg, 6-min walk test) and objective measures (eg, Repeatable Battery for the Assessment of Neuropsychological Status). Participants are mailed a wrist-worn ActiGraph device (ActiGraph LLC) to passively monitor objective function (eg, steps) during the week between the baseline assessment and the beginning of the programs, which they continue to wear throughout the programs. After baseline assessments, participants are randomized to either AB or HEP and complete 8 weekly, remote, group sessions with a Massachusetts General Hospital psychologist. The AB group receives a Fitbit (Fitbit Inc) to help reinforce increased activity. Assessments are repeated after the intervention and at the 6-month follow-up. Coprimary outcomes include multimodal physical function (self-report, performance based, and objective). Secondary outcomes are cognitive function (self-report and objective), emotional function, and pain. RESULTS: We began recruitment in July 2022 and recruited 37 participants across 4 cohorts. Of them, all (n=37, 100%) have completed the baseline assessment, 26 (70%) have completed the posttest assessment, and 9 (24%) are actively enrolled in the intervention (total dropout: n=2, 5%). In the three cohorts (26/37, 70%) that have completed the AB or HEP, 26 (100%) participants completed all 8 group sessions (including minimal makeups), and watch adherence (1937/2072, 93.48%, average across ActiGraph and Fitbit devices) has been excellent. The fourth cohort is ongoing (9/37, 24%), and we plan to complete enrollment by March 2026. CONCLUSIONS: We aim to establish the efficacy of the AB program over a time-matched and dose-matched control in a live video-based trial and test the mechanisms through theoretically driven mediators and moderators. Findings will inform the development of a future multisite effectiveness-implementation trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT05373745; https://classic.clinicaltrials.gov/ct2/show/NCT05373745. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/47319.

Effect of apolipoprotein genotype and educational attainment on cognitive function in autosomal dominant Alzheimer's disease.

Autosomal dominant Alzheimer's disease (ADAD) is genetically determined, but variability in age of symptom onset suggests additional factors may influence cognitive trajectories. Although apolipoprotein E (APOE) genotype and educational attainment both influence dementia onset in sporadic AD, evidence for these effects in ADAD is limited. To investigate the effects of APOE and educational attainment on age-related cognitive trajectories in ADAD, we analyzed data from 675 Presenilin-1 E280A mutation carriers and 594 non-carriers. Here we show that age-related cognitive decline is accelerated in ADAD mutation carriers who also have an APOE e4 allele compared to those who do not and delayed in mutation carriers who also have an APOE e2 allele compared to those who do not. Educational attainment is protective and moderates the effect of APOE on cognition. Despite ADAD mutation carriers being genetically determined to develop dementia, age-related cognitive decline may be influenced by other genetic and environmental factors.

Sex differences in blood biomarkers and cognitive performance in individuals with autosomal dominant Alzheimer's disease.

INTRODUCTION: Plasma tau phosphorylated at threonine 217 (P-tau217) and neurofilament light (NfL) have emerged as markers of Alzheimer's disease (AD) pathology. Few studies have examined the role of sex in plasma biomarkers in sporadic AD, yielding mixed findings, and none in autosomal dominant AD. METHODS: We examined the effects of sex and age on plasma P-tau217 and NfL, and their association with cognitive performance in a cross-sectional study of 621 Presenilin-1 E280A mutation carriers (PSEN1) and non-carriers. RESULTS: As plasma P-tau217 levels increase, cognitively unimpaired female carriers showed better cognitive performance than cognitively unimpaired male carriers. Yet, as disease progresses, female carriers had a greater plasma NfL increase than male carriers. There were no sex differences in the association between age and plasma biomarkers among non-carriers. DISCUSSION: Our findings suggest that, among PSEN1 mutation carriers, females had a greater rate of neurodegeneration than males, yet it did not predict cognitive performance. HIGHLIGHTS: We examined sex differences in plasma P-tau217 and NfL in Presenilin-1 E280A (PSEN1) mutation carriers and non-carriers. Female carriers had a greater plasma NfL increase, but not P-tau217, than male carriers. As plasma P-tau217 levels increase, cognitively unimpaired female carriers showed better cognitive performance than cognitively unimpaired male carriers. The interaction effect of sex by plasma NfL levels did not predict cognition among carriers.

Resilience to autosomal dominant Alzheimer's disease in a Reelin-COLBOS heterozygous man.

We characterized the world's second case with ascertained extreme resilience to autosomal dominant Alzheimer's disease (ADAD). Side-by-side comparisons of this male case and the previously reported female case with ADAD homozygote for the APOE3 Christchurch (APOECh) variant allowed us to discern common features. The male remained cognitively intact until 67 years of age despite carrying a PSEN1-E280A mutation. Like the APOECh carrier, he had extremely elevated amyloid plaque burden and limited entorhinal Tau tangle burden. He did not carry the APOECh variant but was heterozygous for a rare variant in RELN (H3447R, termed COLBOS after the Colombia-Boston biomarker research study), a ligand that like apolipoprotein E binds to the VLDLr and APOEr2 receptors. RELN-COLBOS is a gain-of-function variant showing stronger ability to activate its canonical protein target Dab1 and reduce human Tau phosphorylation in a knockin mouse. A genetic variant in a case protected from ADAD suggests a role for RELN signaling in resilience to dementia.

Subjective cognitive decline across ethnoracial groups in the A4 study.

INTRODUCTION: The associations between subjective cognitive decline (SCD), cognition, and amyloid were explored across diverse participants in the A4 study. METHODS: Five thousand one hundred and fifty-one non-Hispanic White, 262 non-Hispanic Black, 179 Hispanic-White, and 225 Asian participants completed the Preclinical Alzheimer Cognitive Composite (PACC), self- and study partner-reported Cognitive Function Index (CFI). A subsample underwent amyloid positron emission tomography (18 F-florbetapir) (N = 4384). We examined self-reported CFI, PACC, amyloid, and study partner-reported CFI by ethnoracial group. RESULTS: The associations between PACC-CFI and amyloid-CFI were moderated by race. The relationships were weaker or non-significant in non-Hispanic Black and Hispanic White groups. Depression and anxiety scores were stronger predictors of CFI in these groups. Despite group differences in the types of study partners, self- and study partner-CFI were congruent across groups. DISCUSSION: SCD may not uniformly relate to cognition or AD biomarkers in different ethnoracial groups. Nonetheless, self- and study partner-SCD were congruent despite differences in study partner type. Highlights Association between SCD and objective cognition was moderated by ethnoracial group. Association between SCD and amyloid was moderated by ethnoracial group. Depression and anxiety were stronger predictors of SCD in Black and Hispanic groups. Study-partner and self-reported SCD are congruent across groups. Study-partner report was consistent despite difference in study partner types.

APOE and immunity: Research highlights.

INTRODUCTION: At the Alzheimer's Association's APOE and Immunity virtual conference, held in October 2021, leading neuroscience experts shared recent research advances on and inspiring insights into the various roles that both the apolipoprotein E gene (APOE) and facets of immunity play in neurodegenerative diseases, including Alzheimer's disease and other dementias. METHODS: The meeting brought together more than 1200 registered attendees from 62 different countries, representing the realms of academia and industry. RESULTS: During the 4-day meeting, presenters illuminated aspects of the cross-talk between APOE and immunity, with a focus on the roles of microglia, triggering receptor expressed on myeloid cells 2 (TREM2), and components of inflammation (e.g., tumor necrosis factor α [TNFα]). DISCUSSION: This manuscript emphasizes the importance of diversity in current and future research and presents an integrated view of innate immune functions in Alzheimer's disease as well as related promising directions in drug development.

Association of loneliness, social isolation, and daily cognitive function in Mexican older adults living in community during the first wave of COVID-19 pandemic / Asociación del aislamiento social, soledad y la función cognitiva cotidiana en adultos mayores mexicanos de la comunidad durante la primera ola del COVID-19

Abstract Introduction Loneliness and social isolation are known risk factors for cognitive decline; their effect in older adults (OA) after COVID-19 lockdown is emerging. Objective To establish an association between loneliness and social isolation, with daily cognitive function in Mexican OA during the first wave of the COVID-19 pandemic. Method Cross-sectional study, derived from the cohort "The impact of COVID 19 on well-being, cognition, and discrimination among older adults in the United States and Latin America", which included 308 OA recruited between March-August 2020 whose daily cognitive function were determined with the Everyday Cognition Scale (E-Cog) as dichotomized score (cut point: 1.31 for normal cognition). Loneliness and social isolation were binomial variables. Results The mean age was 65.4 ± 7.9 years, 75.7% were women. The mean continuous E-Cog score was 57.4 (SD = ± 19.1), 49.1% had a score < 1.31 (normal cognition), while 50.9% had a higher score (cognitive impairment). Eighty four percent of participants reported loneliness, 79.9% reported social isolation. Multivariate regression model showed a negative and statistically significant association between social isolation and loneliness and E-Cog, adjusted by age, sex and education level (β = -.046, 95% CI = [-.8, -.013], p = .007; β = -.16, 95% CI = [-.08, -.018], p = .003), and a positive association with subjective memory complaint (β = .81, 95% CI = [-.16, -.11], p = < .001). Discussion and conclusion These data suggest the need for increased vigilance of those who have loneliness and social isolation due to its potential deleterious effect on cognitive function.

Resumen Introducción La soledad y el aislamiento social son factores de riesgo conocidos para el deterioro cognitivo; su efecto en las personas mayores (PM) después del confinamiento por COVID-19 está emergiendo. Objetivo Establecer una asociación entre la soledad y el aislamiento social, con la función cognitiva diaria en PM mexicanas durante la primera ola de la pandemia por COVID-19. Método Estudio transversal derivado de la cohorte "The impact of COVID 19 on well-being, cognition, and discrimination among older adults in the United States and Latin America", incluyó 308 AM reclutados de marzo-agosto 2020, la función cognitiva diaria fue evaluada con Everyday Cognition Scale (E-Cog) con un punto de corte 1.31 (cognición normal); la soledad y el aislamiento social fueron variables binomiales. Resultados La media de edad fue 65.4 ± 7.9 años, 75.7% mujeres. E-Cog promedio fue 57.4 (DE = ± 19.1), 49.1 % tenía una puntuación < 1.31 (cognición normal), 50.9% > 1.31 (deterioro cognitivo). Ochenta y cuatro por ciento de los participantes reportaron soledad, 79.9% aislamiento social. El modelo de regresión multivariado mostró una asociación negativa y estadísticamente significativa entre aislamiento social y soledad con E-Cog (β = -.046, IC 95% = [-.8, -.013], p = .007; β = -.16, IC 95% = [-.08, -.018], p = .003), y una asociación positiva con queja de memoria subjetiva (β = .81, IC 95% = [-.16, -.11], p = < .001) ajustado a edad, sexo y escolaridad. Discusión y conclusión Estos datos sugieren la necesidad de una mayor vigilancia de quienes presentan soledad y aislamiento social debido a su potencial efecto deletéreo sobre la función cognitiva.

Waning locus coeruleus integrity precedes cortical tau accrual in preclinical autosomal dominant Alzheimer's disease.

INTRODUCTION: Autopsy studies recognize the locus coeruleus (LC) as one of the first sites accumulating tau in Alzheimer's disease (AD). Recent AD work related in vivo LC magnetic resonance imaging (MRI) integrity to tau and cognitive decline; however, relationships of LC integrity to age, tau, and cognition in autosomal dominant AD (ADAD) remain unexplored. METHODS: We associated LC integrity (3T-MRI) with estimated years of onset, cortical amyloid beta, regional tau (positron emission tomography [PET]) and memory (Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word-List-Learning) among 27 carriers and 27 non-carriers of the presenilin-1 (PSEN1) E280A mutation. Longitudinal changes between LC integrity and tau were evaluated in 10 carriers. RESULTS: LC integrity started to decline at age 32 in carriers, 12 years before clinical onset, and 20 years earlier than in sporadic AD. LC integrity was negatively associated with cortical tau, independent of amyloid beta, and predicted precuneus tau increases. LC integrity was positively associated with memory. DISCUSSION: These findings support LC integrity as marker of disease progression in preclinical ADAD.

Associations Among Loneliness, Purpose in Life and Subjective Cognitive Decline in Ethnoracially Diverse Older Adults Living in the United States.

Subjective cognitive decline (SCD), which precedes Mild Cognitive Impairment and dementia, may be affected by purpose in life (PiL) and loneliness in older adults. We investigated associations among PiL, loneliness, and SCD in US Latino (n = 126), Black (n = 74), Asian (n = 33), and White (n = 637) adults. Higher PiL predicted lower SCD in all groups (p-values < .012), except Black participants. Lower loneliness predicted lower SCD in Latino and White groups (p-values < .05), and PiL moderated this association in White adults. PiL and loneliness may play important roles in cognitive decline. Differential predictors of SCD suggest differential targets for preventing cognitive decline and dementia across ethnoracial groups.

A public resource of baseline data from the Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease Trial.

INTRODUCTION: The Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease (API ADAD) Trial evaluated the anti-oligomeric amyloid beta (Aß) antibody therapy crenezumab in cognitively unimpaired members of the Colombian presenilin 1 (PSEN1) E280A kindred. We report availability, methods employed to protect confidentiality and anonymity of participants, and process for requesting and accessing baseline data. METHODS: We developed mechanisms to share baseline data from the API ADAD Trial in consultation with experts and other groups sharing data from Alzheimer's disease (AD) prevention trials, balancing the need to protect anonymity and trial integrity with making data broadly available to accelerate progress in the field. We pressure-tested deliberate and inadvertent potential threats under specific assumptions, employed a system to suppress or mask both direct and indirect identifying variables, limited and firewalled data managers, and put forth specific principles requisite to receive data. RESULTS: Baseline demographic, PSEN1 E280A and apolipoprotein E genotypes, florbetapir and fluorodeoxyglucose positron emission tomography, magnetic resonance imaging, clinical, and cognitive data can now be requested by interested researchers. DISCUSSION: Baseline data are publicly available; treatment data and biological samples, including baseline and treatment-related blood-based biomarker data will become available in accordance with our original trial agreement and subsequently developed Collaboration for Alzheimer's Prevention principles. Sharing of these data will allow exploration of important questions including the differential effects of initiating an investigational AD prevention therapy both before as well as after measurable Aß plaque deposition.