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OBJECTIVE: Prior studies have reported an association between depression and quality of life (QOL) in Alzheimer's disease (AD), but the effect of self- versus proxy rating of mood and QOL has not been described. DESIGN: In this secondary analysis of data from a cohort study, the authors used a linear mixed-effects model to determine if the association between depression and QOL is affected by whether both measures are assessed by the same member of the patient-caregiver dyad. SETTING: Participants and caregiver informants were recruited from 10 California Alzheimer Disease Centers. PARTICIPANTS: A total of 137 participants with mild-to-moderate Alzheimer's disease and their caregivers. MEASUREMENTS: Self- and proxy-rated scores on both the Geriatric Depression Scale (GDS) and the Quality of Life in Alzheimer's Disease scale (QoL-AD). Multivariable linear mixed-effects models were used to estimate the association between depression and QOL. RESULTS: Results of the multivariable linear mixed-effects models showed a significant association between self-rated QoL-AD and self-rated (B = -0.49, p <0.0001) but not proxy-rated GDS (B = -0.07, p = 0.19) after adjusting for confounders. Likewise, there was a significant association between proxy-rated QoL-AD and proxy-rated GDS (B = -0.48, p <0.0001) but not self-rated GDS (B = 0.05, p = 0.36). CONCLUSION: Depression was associated with QOL in AD over short-term longitudinal follow-up, but the association was not statistically significant if both instruments are not administered to the same member of the patient-caregiver dyad. The choice of self- versus proxy-reported QOL should be intentionally considered in future studies as it may influence reported outcomes.
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Doença de Alzheimer , Humanos , Idoso , Doença de Alzheimer/complicações , Qualidade de Vida , Depressão/epidemiologia , Depressão/complicações , Estudos de Coortes , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , CuidadoresRESUMO
OBJECTIVE: Physical and recreational activities are behaviors that may modify risk of late-life cognitive decline. We sought to examine the role of retrospectively self-reported midlife (age 40) physical and recreational activity engagement - and self-reported change in these activities from age 40 to initial study visit - in predicting late-life cognition. METHOD: Data were obtained from 898 participants in a longitudinal study of cognitive aging in demographically and cognitively diverse older adults (Age: range = 49-93 years, M = 75, SD = 7.19). Self-reported physical and recreational activity participation at age 40 and at the initial study visit were quantified using the Life Experiences Assessment Form. Change in activities was modeled using latent change scores. Cognitive outcomes were obtained annually (range = 2-17 years) using the Spanish and English Neuropsychological Assessment Scales, which measure verbal episodic memory, semantic memory, visuospatial processing, and executive functioning. RESULTS: Physical activity engagement at age 40 was strongly associated with cognitive performance in all four domains at the initial visit and with global cognitive slope. However, change in physical activities after age 40 was not associated with cognitive outcomes. In contrast, recreational activity engagement - both at age 40 and change after 40 - was predictive of cognitive intercepts and slope. CONCLUSIONS: Retrospectively self-reported midlife physical and recreational activity engagement were strongly associated with late-life cognition - both level of performance and rate of future decline. However, the data suggest that maintenance of recreational activity engagement (e.g., writing, taking classes, reading) after age 40 is more strongly associated with late-life cognition than continued maintenance of physical activity levels.
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Envelhecimento , Memória Episódica , Humanos , Idoso , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Estudos Longitudinais , Autorrelato , Estudos Retrospectivos , Envelhecimento/psicologia , CogniçãoRESUMO
INTRODUCTION: The U.S. study to protect brain health through lifestyle intervention to reduce risk (U.S. POINTER) is conducted to confirm and expand the results of the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) in Americans. METHODS: U.S. POINTER was planned as a 2-year randomized controlled trial of two lifestyle interventions in 2000 older adults at risk for dementia due to well-established factors. The primary outcome is a global cognition composite that permits harmonization with FINGER. RESULTS: U.S. POINTER is centrally coordinated and conducted at five clinical sites (ClinicalTrials.gov: NCT03688126). Outcomes assessments are completed at baseline and every 6 months. Both interventions focus on exercise, diet, cognitive/social stimulation, and cardiovascular health, but differ in intensity and accountability. The study partners with a worldwide network of similar trials for harmonization of methods and data sharing. DISCUSSION: U.S. POINTER is testing a potentially sustainable intervention to support brain health and Alzheimer's prevention for Americans. Impact is strengthened by the targeted participant diversity and expanded scientific scope through ancillary studies.
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Disfunção Cognitiva , Humanos , Idoso , Disfunção Cognitiva/psicologia , Estilo de Vida , Cognição , Exercício Físico , EncéfaloRESUMO
BACKGROUND: Understanding the neurobiological underpinnings between established multimodal dementia risk factors and noninvasive blood-based biomarkers may lead to greater precision and earlier identification of older adults at risk of accelerated decline and dementia. We examined whether key vascular and genetic risk impact the association between cerebral amyloid burden and plasma aß (amyloid ß) 42/40 in nondemented older adults. METHODS: We used nondemented older adults from the UCD-ADRC (University of California, Davis-Alzheimer's Disease Research Center) study (n=96) and Alzheimer's Disease Neuroimaging Initiative (n=104). Alzheimer's Disease Neuroimaging Initiative was examined as confirmatory study cohort. We followed a cross-sectional design and examined linear regression followed by mediation analyses. Vascular risk score was obtained as the sum of hypertension, diabetes, hyperlipidemia, coronary artery disease, and cerebrovascular disease. Apolipoprotein E (APOE) ε4+ risk was genotyped, and plasma aß42 and aß40 were assayed. Cerebral amyloid burden was quantified using Florbetapir-PET scans. Baseline age was included as a covariate in all models. RESULTS: Vascular risk significantly predicted cerebral amyloid burden in Alzheimer's Disease Neuroimaging Initiative but not in the UCD-ADRC cohort. Cerebral amyloid burden was associated with plasma aß 42/40 in both cohorts. Higher vascular risk increased cerebral amyloid burden was indirectly associated with reduced plasma aß 42/40 in Alzheimer's Disease Neuroimaging Initiative but not in UCD-ADRC cohort. However, when stratified by APOE ε4+ risk, we consistently observed this indirect relationship only in APOE ε4+ carriers across both cohorts. CONCLUSIONS: Vascular risk is indirectly associated with the level of plasma aß 42/40 via cerebral amyloid burden only in APOE ε4+ carriers. Nondemented older adults with genetic vulnerability to dementia and accelerated decline may benefit from careful monitoring of vascular risk factors directly associated with cerebral amyloid burden and indirectly with plasma aß 42/40.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Humanos , Idoso , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Estudos Transversais , Encéfalo/metabolismo , Tomografia por Emissão de Pósitrons , AmiloideRESUMO
Currently, over 16 million dementia caregivers in the US provide over 18 billion hours of care. As the number of persons living with dementia increases, so too will the number of family caregivers. Given the projected steady growth in caregivers and their health-related needs in caring for persons living with Alzheimer disease and related dementias, several initiatives are underway that focus on caregivers. One overlooked mechanism to meet caregiver needs is the National Institute on Aging's Alzheimer's Disease Research Centers (ADRCs). Through secondary analysis, we present a picture of dementia caregiving from the National Alzheimer's Coordinating Center's database and discuss a call to action for ADRCs to engage caregivers and further support the mission of the ADRC to advance the field of dementia research.
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Doença de Alzheimer , Cuidadores , Doença de Alzheimer/terapia , HumanosRESUMO
OBJECTIVE: This study compared the level of education and tests from multiple cognitive domains as proxies for cognitive reserve. METHOD: The participants were educationally, ethnically, and cognitively diverse older adults enrolled in a longitudinal aging study. We examined independent and interactive effects of education, baseline cognitive scores, and MRI measures of cortical gray matter change on longitudinal cognitive change. RESULTS: Baseline episodic memory was related to cognitive decline independent of brain and demographic variables and moderated (weakened) the impact of gray matter change. Education moderated (strengthened) the gray matter change effect. Non-memory cognitive measures did not incrementally explain cognitive decline or moderate gray matter change effects. CONCLUSIONS: Episodic memory showed strong construct validity as a measure of cognitive reserve. Education effects on cognitive decline were dependent upon the rate of atrophy, indicating education effectively measures cognitive reserve only when atrophy rate is low. Results indicate that episodic memory has clinical utility as a predictor of future cognitive decline and better represents the neural basis of cognitive reserve than other cognitive abilities or static proxies like education.
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Disfunção Cognitiva , Reserva Cognitiva , Memória Episódica , Idoso , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Escolaridade , HumanosRESUMO
OBJECTIVE: The Everyday Compensation scale (EComp) is an informant-rated questionnaire designed to measure cognitively based compensatory strategies that support both everyday memory and executive function in the context of completing instrumental activities of daily living (IADLs). Although previous findings provided early support for the usefulness of the initial version of EComp, the current paper further describes the development, refinement, and validation of EComp as a new assessment tool of compensation for IADLs. METHOD: Confirmatory factor analysis (CFA) was used to examine its factor structure. Convergent and predictive validity was evaluated by examining the relationship between EComp and markers of disease, including diagnosis, cognitive change, and trajectories of functional abilities. RESULTS: CFA supported a general compensation factor after accounting for variance attributable to IADL domain-specific engagement. The clinical groups differed in compensatory strategy use, with those with dementia using significantly fewer compensatory strategies as compared to individuals with normal cognition or mild cognitive impairment. Greater levels of compensation were related to better cognitive functions (memory and executive function) and functional abilities, as well as slower rates of cognitive and functional decline over time. Importantly, higher levels of compensation were associated with less functional difficulties and subsequently slower rate of functional decline independent of the level of cognitive impairment. CONCLUSIONS: Engagement in compensatory strategies among older adults has important implications for prolonging functional independence, even in those with declining cognitive functioning. Results suggest that the revised EComp is likely to be useful in measuring cognitively based compensation in older adults.
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Atividades Cotidianas , Envelhecimento Cognitivo , Disfunção Cognitiva/diagnóstico , Demência/diagnóstico , Função Executiva , Testes Neuropsicológicos/normas , Psicometria/normas , Idoso , Idoso de 80 Anos ou mais , Envelhecimento Cognitivo/fisiologia , Disfunção Cognitiva/fisiopatologia , Demência/fisiopatologia , Função Executiva/fisiologia , Análise Fatorial , Feminino , Humanos , Estudos Longitudinais , Masculino , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Subjective cognitive decline (SCD) may represent a low-burden indicator of dementia risk. The value of SCD as a proxy marker, however, depends on the consistency of associations between subjective and objective cognitive measures across sociodemographic and psychological factors. METHODS: We evaluated baseline data from the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) study (n=1615). SCD was measured using the 12-item Everyday Cognition (ECog) scale. Using linear regression models with interaction terms, we evaluated 6 potential modifiers (age, sex, race/ethnicity, educational attainment, family history of dementia, and depressive symptoms) of the association between cognitive performance (episodic memory, executive function) and SCD. RESULTS: Lower episodic memory and executive function scores were associated with higher log(ECog scores) (more SCD). Older age and elevated depressive symptoms were associated with higher log(ECog scores). Age (interaction P=0.002) and education (interaction P=0.01) modified the association between executive function and log(ECog scores). Specifically, associations between executive function and log(ECog scores) were stronger among participants with more education and less pronounced among older participants. CONCLUSIONS: The association between cognitive performance and log(ECog scores) differed little across sociodemographic and psychological factors. SCD as measured by the ECog may be a valuable proxy for cognitive performance in diverse older adults.
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Disfunção Cognitiva , Etnicidade/estatística & dados numéricos , Testes Neuropsicológicos/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , California , Disfunção Cognitiva/etnologia , Disfunção Cognitiva/psicologia , Estudos de Coortes , Feminino , Humanos , Vida Independente , Masculino , Fatores SexuaisRESUMO
OBJECTIVES: Careful characterization of how functional decline co-evolves with cognitive decline in older adults has yet to be well described. Most models of neurodegenerative disease postulate that cognitive decline predates and potentially leads to declines in everyday functional abilities; however, there is mounting evidence that subtle decline in instrumental activities of daily living (IADLs) may be detectable in older individuals who are still cognitively normal. METHODS: The present study examines how the relationship between change in cognition and change in IADLs are best characterized among older adults who participated in the ACTIVE trial. Neuropsychological and IADL data were analyzed for 2802 older adults who were cognitively normal at study baseline and followed for up to 10 years. RESULTS: Findings demonstrate that subtle, self-perceived difficulties in performing IADLs preceded and predicted subsequent declines on cognitive tests of memory, reasoning, and speed of processing. CONCLUSIONS: Findings are consistent with a growing body of literature suggesting that subjective changes in everyday abilities can be associated with more precipitous decline on objective cognitive measures and the development of mild cognitive impairment and dementia. (JINS, 2018, 24, 104-112).
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Atividades Cotidianas , Envelhecimento/fisiologia , Disfunção Cognitiva/fisiopatologia , Autoavaliação Diagnóstica , Sintomas Prodrômicos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Disfunção Cognitiva/psicologia , Feminino , Seguimentos , Humanos , MasculinoRESUMO
Elucidating the mechanisms by which late-life neurodegeneration causes cognitive decline requires understanding why some individuals are more resilient than others to the effects of brain change on cognition (cognitive reserve). Currently, there is no way of measuring cognitive reserve that is valid (e.g. capable of moderating brain-cognition associations), widely accessible (e.g. does not require neuroimaging and large sample sizes), and able to provide insight into resilience-promoting mechanisms. To address these limitations, this study sought to determine whether a machine learning approach to combining standard clinical variables could (i) predict a residual-based cognitive reserve criterion standard and (ii) prospectively moderate brain-cognition associations. In a training sample combining data from the University of California (UC) Davis and the Alzheimer's Disease Neuroimaging Initiative-2 (ADNI-2) cohort (N = 1665), we operationalized cognitive reserve using an MRI-based residual approach. An eXtreme Gradient Boosting machine learning algorithm was trained to predict this residual reserve index (RRI) using three models: Minimal (basic clinical data, such as age, education, anthropometrics, and blood pressure), Extended (Minimal model plus cognitive screening, word reading, and depression measures), and Full [Extended model plus Clinical Dementia Rating (CDR) and Everyday Cognition (ECog) scale]. External validation was performed in an independent sample of ADNI 1/3/GO participants (N = 1640), which examined whether the effects of brain change on cognitive change were moderated by the machine learning models' cognitive reserve estimates. The three machine learning models differed in their accuracy and validity. The Minimal model did not correlate strongly with the criterion standard (r = 0.23) and did not moderate the effects of brain change on cognitive change. In contrast, the Extended and Full models were modestly correlated with the criterion standard (r = 0.49 and 0.54, respectively) and prospectively moderated longitudinal brain-cognition associations, outperforming other cognitive reserve proxies (education, word reading). The primary difference between the Minimal model-which did not perform well as a measure of cognitive reserve-and the Extended and Full models-which demonstrated good accuracy and validity-is the lack of cognitive performance and informant-report data in the Minimal model. This suggests that basic clinical variables like anthropometrics, vital signs, and demographics are not sufficient for estimating cognitive reserve. Rather, the most accurate and valid estimates of cognitive reserve were obtained when cognitive performance data-ideally augmented by informant-reported functioning-was used. These results indicate that a dynamic and accessible proxy for cognitive reserve can be generated for individuals without neuroimaging data and gives some insight into factors that may promote resilience.
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Prior research has shown that some personality traits are associated with cognitive outcomes and may confirm risk or protection against cognitive decline. The present study expands on previous work to examine the association between a more comprehensive set of psychological characteristics and cognitive performance in a diverse cohort of older adults. We also examine whether controlling for brain atrophy influences the association between psychological characteristics and cognitive function. A total of 157 older adults completed a battery of psychological questionnaires (Openness to Experience, Conscientiousness, Agreeableness, Neuroticism, Extraversion, positive affect, negative affect-sadness, negative affect-anger, sense of purpose, loneliness, grit, and self-efficacy). Cognitive outcomes were measured across multiple domains: episodic memory, semantic memory, executive function, and spatial ability. Baseline brain (MRI) variables included gray matter, hippocampus, and total white matter hyperintensity volume. Parallel process, multilevel models yielded intercept (individual cognitive domain scores) and linear slope (global cognitive change) random effects for the cognitive outcomes. Positive affect (ß = 0.013, SE = 0.005, p = .004) and Openness (ß = 0.018, SE = 0.007, p = .009) were associated with less cognitive change, independent of baseline brain variables and covariates. Greater sadness predicted more cognitive decline when controlling for covariates, but not brain atrophy. A variety of psychological characteristics were associated with the cross-sectional measures of cognition. This study highlights the important impact of positive and negative affect on reducing or enhancing the risk of longitudinal cognitive decline. Such findings are especially important, given the available efficacious interventions that can improve affect. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Disfunção Cognitiva , Memória Episódica , Humanos , Idoso , Estudos Transversais , Envelhecimento/psicologia , Personalidade , Cognição , AtrofiaRESUMO
OBJECTIVES: Understanding racial/ethnic disparities in late-life cognitive health is a public health imperative. We used baseline data from the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) study to examine how age, education, gender, and clinical diagnosis, a proxy for brain health, are associated with cross-sectional measures of cognition in diverse racial/ethnic groups. METHODS: Comprehensive measures of cognition were obtained using the Spanish and English Neuropsychological Assessment Scales and the National Institutes of Health Toolbox Cognitive Health Battery in a sample of 1,695 KHANDLE participants (Asians 24%, Blacks 26%, Latinos 20%, Whites 29%). A 25% random subsample was clinically evaluated and diagnosed with normal cognition, mild cognitive impairment (MCI), or dementia. Cognitive test scores were regressed on core demographic variables and diagnosis in the combined sample and in multiple group analyses stratified by racial/ethnic group. RESULTS: Race/ethnicity and education were variably associated with test scores with strongest associations with tests of vocabulary and semantic memory. Older age was associated with poorer performance on all measures, and gender differences varied across cognitive tests. Clinical diagnosis of MCI or dementia was associated with average decrements in test scores that ranged from -0.41 to -0.84 SD, with largest differences on tests of executive function and episodic memory. With few exceptions, associations of demographic variables and clinical diagnosis did not differ across racial/ethnic groups. DISCUSSION: The robust associations of cognitive test results with clinical diagnosis independent of core demographic variables and race/ethnicity support the validity of cognitive tests as indicators for brain health in diverse older adults.
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Cognição , Envelhecimento Cognitivo , Disfunção Cognitiva , Etnicidade , Função Executiva , Idoso , Envelhecimento Cognitivo/fisiologia , Envelhecimento Cognitivo/psicologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etnologia , Comparação Transcultural , Diversidade Cultural , Escolaridade , Etnicidade/educação , Etnicidade/psicologia , Etnicidade/estatística & dados numéricos , Feminino , Envelhecimento Saudável/etnologia , Envelhecimento Saudável/psicologia , Humanos , Acontecimentos que Mudam a Vida , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Estados Unidos/epidemiologiaRESUMO
Introduction: We examine whether the association between key plasma biomarkers (amyloid ß [aß] 42/40, total tau (t-tau), neurofilament light [NfL]) and cognitive trajectories (executive function [EF] and episodic memory [EM]) is mediated through neurodegeneration. Methods: All participants were recruited from the University of California, Davis-Alzheimer's Disease Research Center (n = 473; baseline age range = 49-95 years, 60% women). We applied an accelerated longitudinal design to test latent growth models for EF and EM, and path and mediation analyses. Age was centered at 75 years, and all models were adjusted for sex, education, and ethnicity. Results: HV differentially mediated the association aß 42/40 and NfL on EF and EM level and change. Hippocampal volume (HV) did not mediate the association between t-tau and cognitive performance. Discussion: Neurodegeneration as represented with HV selectively mediates the association between key non-invasive plasma biomarkers and cognitive trajectories in an ethnoracially and clinically diverse community-based sample.
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BACKGROUND: Cognitive impairment, including dementia, is frequently under-detected in primary care. The Consortium for Detecting Cognitive Impairment, including Dementia (DetectCID) convenes three multidisciplinary teams that are testing novel paradigms to improve the frequency and quality of patient evaluations for detecting cognitive impairment in primary care and appropriate follow-up. OBJECTIVE: Our objective was to characterize the three paradigms, including similarities and differences, and to identify common key lessons from implementation. METHODS: A qualitative evaluation study with dementia specialists who were implementing the detection paradigms. Data was analyzed using content analysis. RESULTS: We identified core components of each paradigm. Key lessons emphasized the importance of engaging primary care teams, enabling primary care providers to diagnose cognitive disorders and provide ongoing care support, integrating with the electronic health record, and ensuring that paradigms address the needs of diverse populations. CONCLUSION: Approaches are needed that address the arc of care from identifying a concern to post-diagnostic management, are efficient and adaptable to primary care workflows, and address a diverse aging population. Our work highlights approaches to partnering with primary care that could be useful across specialties and paves the way for developing future paradigms that improve differential diagnosis of symptomatic cognitive impairment, identifying not only its presence but also its specific syndrome or etiology.
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Transtornos Cognitivos , Disfunção Cognitiva , Demência , Idoso , Transtornos Cognitivos/diagnóstico , Disfunção Cognitiva/diagnóstico , Demência/diagnóstico , Demência/psicologia , Diagnóstico Diferencial , Humanos , Atenção Primária à SaúdeRESUMO
Cognitive reserve is thought to reflect life experiences. Which experiences contribute to reserve and their relative importance is not understood. Subjects were 652 autopsied cases from the Rush Memory and Aging Project and the Religious Orders Study. Reserve was defined as the residual variance of the regressions of cognitive factors on brain pathology and was captured in a latent variable that was regressed on potential determinants of reserve. Neuropathology variables included Alzheimer's disease markers, Lewy bodies, infarcts, microinfarcts, and brain weight. Cognition was measured with six cognitive domain scores. Determinants of reserve were socioeconomic status (SES), education, leisure cognitive activities at age 40 (CA40) and at study enrollment (CAbaseline) in late life. The four exogenous predictors of reserve were weakly to moderately inter-correlated. In a multivariate model, all except SES had statistically significant effects on Reserve, the strongest of which were CA40 (ß = .31) and CAbaseline (ß = .28). The Education effect was negative in the full model (ß = -.25). Results suggest that leisure cognitive activities throughout adulthood are more important than education in determining reserve. Discrepancies between cognitive activity and education may be informative in estimating late life reserve.
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Cognição/fisiologia , Reserva Cognitiva/fisiologia , Escolaridade , Adulto , Doença de Alzheimer/psicologia , Autopsia , Criança , Feminino , Humanos , Estudos Longitudinais , Transtornos Mentais/psicologia , Testes Neuropsicológicos , Estado Nutricional , Gravidez , Cuidado Pré-Natal , Meio Social , Fatores SocioeconômicosRESUMO
Studies of neuropathology-cognition associations are not common and have been limited by small sample sizes, long intervals between autopsy and cognitive testing, and lack of breadth of neuropathology and cognition variables. This study examined domain-specific effects of common neuropathologies on cognition using data (N = 652) from two large cohort studies of older adults. We first identified dimensions of a battery of 17 neuropsychological tests, and regional measures of Alzheimer's disease (AD) neuropathology. We then evaluated how cognitive factors were related to dimensions of AD and additional measures of cerebrovascular and Lewy Body disease, and also examined independent effects of brain weight. All cognitive domains had multiple neuropathology determinants that differed by domain. Neocortical neurofibrillary tangles were the strongest predictors of most domains, while medial temporal tangles showed a weaker relationship with episodic memory. Neuritic plaques had relatively strong effects on multiple domains. Lewy bodies and macroscopic infarcts were associated with all domains, while microscopic infarcts had more limited associations. Brain weight was related to all domains independent of specific neuropathologies. Results show that cognition is complexly determined by multiple disease substrates. Neuropathological variables and brain weight contributed approximately a third to half of the explained variance in different cognitive domains.
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Cognição/fisiologia , Doenças do Sistema Nervoso/psicologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Doença de Alzheimer/psicologia , Encéfalo/patologia , Infarto Cerebral/patologia , Transtornos Cerebrovasculares/psicologia , Estudos de Coortes , Análise Fatorial , Feminino , Humanos , Doença por Corpos de Lewy/psicologia , Estudos Longitudinais , Masculino , Memória/fisiologia , Doenças do Sistema Nervoso/patologia , Placa Amiloide/patologia , Percepção Visual/fisiologiaRESUMO
BACKGROUND: This study describes the development and validation of a shortened version of the Everyday Cognition (ECog) scales [Tomaszewski Farias et al. Neuropsychology 2008;22:531-44], an informant-rated questionnaire designed to detect cognitive and functional decline. METHODS: External, convergent, and divergent validities and internal consistency were examined. Data were derived from informant ratings of 907 participants who were either cognitively normal, had mild cognitive impairment (MCI), or had dementia. RESULTS: Twelve items were included in the shortened version (ECog-12). The ECog-12 strongly correlated with established functional measures and neuropsychological scores, only weakly with age and education, and demonstrated high internal consistency. The ECog-12 showed excellent discrimination between the dementia and normal groups (area under the receiver operator characteristic curve = 0.95, CI = 0.94-0.97), and showed promise in discriminating normal older adults from those with any cognitive impairment (i.e., MCI or dementia). Discrimination between the MCI and normal groups was poor. CONCLUSIONS: The ECog-12 shows promise as a clinical tool for assisting clinicians in identifying individuals with dementia.
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Transtornos Cognitivos/diagnóstico , Testes Neuropsicológicos , Idoso , Área Sob a Curva , Feminino , Humanos , Masculino , Psicometria , Curva ROCRESUMO
OBJECTIVE: Late-life changes in cognition and brain integrity are both highly multivariate, time-dependent processes that are essential for understanding cognitive aging and neurodegenerative disease outcomes. The present study seeks to identify a latent variable model capable of efficiently reducing a multitude of structural brain change magnetic resonance imaging (MRI) measurements into a smaller number of dimensions. We further seek to demonstrate the validity of this model by evaluating its ability to reproduce patterns of coordinated brain volume change and to explain the rate of cognitive decline over time. METHOD: We used longitudinal cognitive data and structural MRI scans, obtained from a diverse sample of 358 participants (Mage = 74.81, SD = 7.17), to implement latent variable models for measuring brain change and to estimate the effects of these brain change factors on cognitive decline. RESULTS: Results supported a bifactor model for brain change with four group factors (prefrontal, temporolimbic, medial temporal, and posterior association) and one general change factor (global atrophy). Atrophy in the global (ß = 0.434, SE = 0.070), temporolimbic (ß = 0.275, SE = 0.085), and medial temporal (ß = 0.240, SE = 0.085) factors were the strongest predictors of global cognitive decline. Overall, the brain change model explained 59% of the variance in global cognitive slope. CONCLUSIONS: The current results suggest that brain change across 27 bilateral regions of interest can be grouped into five change factors, three of which (global gray matter, temporolimbic, and medial temporal lobe atrophy) are strongly associated with cognitive decline. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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Disfunção Cognitiva , Doenças Neurodegenerativas , Idoso , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cognição , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Doenças Neurodegenerativas/patologiaRESUMO
INTRODUCTION: Composite scores based on psychometrically rigorous cognitive assessments are well suited for early diagnosis and disease monitoring. METHODS: We developed and cross-validated the Brain Health Assessment-Cognitive Score (BHA-CS), based on a brief computerized battery, in 451 cognitively normal (CN) and 399 cognitively impaired (mild cognitive impairment [MCI] or dementia) older adults. We investigated its long-term reliability and reliable change indices at longitudinal follow-up (N = 340), and the association with amyloid beta (Aß) burden in the CN subgroup with Aß positron emission tomography (N = 119). RESULTS: The BHA-CS was accurate at detecting cognitive impairment and exhibited excellent long-term stability. Reliable decline over one year was detected in 75% of participants with dementia, 44% with MCI, and 3% of CN. Among CN, the Aß-positive group showed worse longitudinal performance on the BHA-CS compared to the Aß-negative group. DISCUSSION: The BHA-CS is sensitive to cognitive decline in preclinical and prodromal neurodegenerative disease.
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BACKGROUND: Impairment in daily functioning is a clinical hallmark of dementia. Difficulties with "instrumental activities of daily living" (IADL) seem to increase gradually over the course of Alzheimer's disease (AD), before dementia onset. However, it is currently not well established how difficulties develop along the preclinical and prodromal stages of AD. We aimed to investigate the trajectories of decline in IADL performance, as reported by a study partner, along the early stages of AD. METHODS: In a longitudinal multicenter study, combining data from community-based and memory clinic cohorts, we included 1555 individuals (mean age 72.5 ± 7.8 years; 50% female) based on availability of amyloid biomarkers, longitudinal IADL data, and clinical information at baseline. Median follow-up duration was 2.1 years. All amyloid-positive participants (n = 982) were classified into the National Institute on Aging-Alzheimer's Association (NIA-AA) clinical stages ranging from preclinical AD (1) to overt dementia (4+). Cognitively normal amyloid-negative individuals (n = 573) served as a comparison group. The total scores of three study-partner reported IADL questionnaires were standardized. RESULTS: The rate of decline in cognitively normal (stage 1) individuals with and without abnormal amyloid did not differ (p = .453). However, from stage 2 onwards, decline was significantly faster in individuals on the AD continuum (B [95%CI] = - 0.32 [- 0.55, - 0.09], p = .007). The rate of decline increased with each successive stage: one standard deviation (SD) unit per year in stage 3 (- 1.06 [- 1.27, - 0.85], p < .001) and nearly two SD units per year in stage 4+ (1.93 [- 2.19, - 1.67], p < .001). Overall, results were similar between community-based and memory clinic study cohorts. CONCLUSIONS: Our results suggest that the rate of functional decline accelerates along the AD continuum, as shown by steeper rates of decline in each successive NIA-AA clinical stage. These results imply that incremental changes in function are a meaningful measure for early disease monitoring. Combined with the low-cost assessment, this advocates the use of these functional questionnaires for capturing the effects of early AD-related cognitive decline on daily life.