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1.
Comput Biol Med ; 176: 108606, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38763068

RESUMEN

This paper presents a deep learning method using Natural Language Processing (NLP) techniques, to distinguish between Mild Cognitive Impairment (MCI) and Normal Cognitive (NC) conditions in older adults. We propose a framework that analyzes transcripts generated from video interviews collected within the I-CONECT study project, a randomized controlled trial aimed at improving cognitive functions through video chats. Our proposed NLP framework consists of two Transformer-based modules, namely Sentence Embedding (SE) and Sentence Cross Attention (SCA). First, the SE module captures contextual relationships between words within each sentence. Subsequently, the SCA module extracts temporal features from a sequence of sentences. This feature is then used by a Multi-Layer Perceptron (MLP) for the classification of subjects into MCI or NC. To build a robust model, we propose a novel loss function, called InfoLoss, that considers the reduction in entropy by observing each sequence of sentences to ultimately enhance the classification accuracy. The results of our comprehensive model evaluation using the I-CONECT dataset show that our framework can distinguish between MCI and NC with an average area under the curve of 84.75%.

2.
J Am Geriatr Soc ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38581144

RESUMEN

BACKGROUND: Policymakers advocate care integration models to enhance Medicare and Medicaid service coordination for dually eligible individuals. One rapidly expanding model is the fully integrated dual eligible (FIDE) plan, a sub-type of the dual eligible special needs plan (D-SNP) in which a parent insurer manages Medicare and Medicaid spending for dually eligible individuals. We examined healthcare utilization differences among dually eligible individuals aged 65 years or older enrolled in D-SNPs by plan type (FIDE vs non-FIDE). METHODS: Using 2018 Medicare Advantage encounters and Medicaid claims of FIDE and non-FIDE enrollees in six states (AZ, CA, FL, NY, TN, WI), we compared healthcare utilization between plan types, adjusting for enrollee characteristics and county indicators. We applied propensity score weighting to address differences between FIDE and non-FIDE plan enrollees. RESULTS: In our main analysis, which included all dually eligible individuals in our sample, we observed no significant difference in healthcare utilization between FIDE and non-FIDE plan enrollees. However, we identified some differences in healthcare utilization between FIDE and non-FIDE plan enrollees in subgroup analyses. For example, among home and community-based service (HCBS) users, FIDE plan enrollees had 6.0 fewer hospitalizations per 1000 person-months (95% CI: -7.9, -4.0) and were 7.0 percentage points more likely to be discharged to home (95% CI: 2.6, 11.5) after hospitalization, compared to non-FIDE plan enrollees. CONCLUSION: While we found no differences in healthcare utilization between FIDE and non-FIDE plan enrollees when considering all dually eligible individuals in our sample, some differences emerged when focusing on subgroups. For example, HCBS users with FIDE plans had fewer hospitalizations and were more likely to be discharged to their home following hospitalization, compared to HCBS users with non-FIDE plans. These findings suggest that FIDE plans may improve care coordination for specific subsets of dually eligible individuals.

3.
Alzheimers Dement ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38629888

RESUMEN

INTRODUCTION: Age-related magnetic resonance imaging (MRI) T2 white matter hyperintensities (WMHs) are common and associated with neurological decline. We investigated the histopathological underpinnings of MRI WMH and surrounding normal appearing white matter (NAWM), with a focus on astroglial phenotypes. METHODS: Brain samples from 51 oldest old Oregon Alzheimer's Disease Research Center participants who came to autopsy underwent post mortem (PM) 7 tesla MRI with targeted histopathological sampling of WMHs and NAWM. Stained slides were digitized and quantified. Mixed-effects models determined differences in molecular characteristics between WMHs and the NAWM and across NAWM. RESULTS: PM MRI-targeted WMHs are characterized by demyelination, microglial activation, and prominent astrocytic alterations, including disrupted aquaporin (AQP) expression. Similar changes occur within the surrounding NAWM in a pattern of decreasing severity with increased distance from WMHs. DISCUSSION: Decreased AQP expression within WMH and proximal NAWM suggest an overwhelmed system wherein water homeostasis is no longer maintained, contributing to WM damage in older individuals. HIGHLIGHTS: Post mortem magnetic resonance imaging (MRI) was used to characterize the pathology of white matter hyperintensities (WMHs) and surrounding normal appearing white matter (NAWM). Stained immunohistochemical (IHC) slides from targeted WMH and NAWM samples were digitized and quantified. WMHs and NAWM were associated with inflammation, demyelination, and gliosis. WMHs and NAWM astrocytic changes included decreased AQP1 and AQP4 expression. Abnormal NAWM pathology diminished in severity with increasing distance from WMH.

4.
J Alzheimers Dis Rep ; 8(1): 531-542, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38549634

RESUMEN

Background: Social engagement has beneficial effects during cognitive aging. Large-scale cognitive brain network functions are implicated in both social behaviors and cognition. Objective: We evaluated associations between functional connectivity (FC) of large-scale brain cognitive networks and social engagement, characterized by self-reported social network size and contact frequency. We subsequently tested large-scale brain network FC as a potential mediator of the beneficial relationship between social engagement and cognitive performance. Methods: 112 older adults (70.7±7.3 years, range 54.6-89.7; 84 women) completed the Lubben Social Network Scale 6 (LSNS-6), National Alzheimer's Coordinating Center (NACC) Uniform Data Set 3 (UDS-3) cognitive battery, and resting state fMRI. We completed seed-based correlational analysis in the default mode and salience networks. Significant associations between social engagement scores and cognitive performance, as well as between social engagement and FC of brain networks, informed the construction of mediation models. Results: Social engagement was significantly associated with executive function and global cognition, with greater social engagement associated with better cognitive performance. Social engagement was significantly associated with salience network FC, with greater social engagement associated with higher connectivity. Salience network FC partially mediated associations between social engagement and both executive function and global cognition. Conclusions: Our results suggest that the salience network is a key mediator of the beneficial relationship between social engagement and cognition in older adults.

5.
Alzheimers Dement (N Y) ; 10(1): e12440, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38356471

RESUMEN

INTRODUCTION: While Alzheimer's disease (AD) is defined by amyloid-ß plaques and tau tangles in the brain, it is evident that many other pathophysiological processes such as inflammation, neurovascular dysfunction, oxidative stress, and metabolic derangements also contribute to the disease process and that varying contributions of these pathways may reflect the heterogeneity of AD. Here, we used a previously validated panel of cerebrospinal fluid (CSF) biomarkers to explore the degree to which different pathophysiological domains are dysregulated in AD and how they relate to each other. METHODS: Twenty-five CSF biomarkers were analyzed in individuals with a clinical diagnosis of AD verified by positive CSF AD biomarkers (AD, n = 54) and cognitively unimpaired controls negative for CSF AD biomarkers (CU-N, n = 26) using commercial single- and multi-plex immunoassays. RESULTS: We noted that while AD was associated with increased levels of only three biomarkers (MMP-10, FABP3, and 8OHdG) on a group level, half of all AD participants had increased levels of biomarkers belonging to at least two pathophysiological domains reflecting the diversity in AD. LASSO modeling showed that a panel of FABP3, 24OHC, MMP-10, MMP-2, and 8OHdG constituted the most relevant and minimally correlated set of variables differentiating AD from CU-N. Interestingly, factor analysis showed that two markers of metabolism and oxidative stress (24OHC and 8OHdG) contributed independent information separate from MMP-10 and FABP3 suggestive of two independent pathophysiological pathways in AD, one reflecting neurodegeneration and vascular pathology, and the other associated with metabolism and oxidative stress. DISCUSSION: Better understanding of the heterogeneity among individuals with AD and the different contributions of pathophysiological processes besides amyloid-ß and tau will be crucial for optimizing personalized treatment strategies. Highlights: A panel of 25 highly validated biomarker assays were measured in CSF.MMP10, FABP3, and 8OHdG were increased in AD in univariate analysis.Many individuals with AD had increased levels of more than one biomarker.Markers of metabolism and oxidative stress contributed to an AD multianalyte profile.Assessing multiple biomarker domains is important to understand disease heterogeneity.

6.
Gerontologist ; 64(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37935416

RESUMEN

BACKGROUND AND OBJECTIVES: Social isolation is a risk factor for cognitive decline and dementia. We conducted a randomized controlled clinical trial (RCT) of enhanced social interactions, hypothesizing that conversational interactions can stimulate brain functions among socially isolated older adults without dementia. We report topline results of this multisite RCT (Internet-based conversational engagement clinical trial [I-CONECT]; NCT02871921). RESEARCH DESIGN AND METHODS: The experimental group received cognitively stimulating semistructured conversations with trained interviewers via internet/webcam 4 times per week for 6 months (induction) and twice per week for an additional 6 months (maintenance). The experimental and control groups both received weekly 10 minutes telephone check-ins. Protocol modifications were required due to the coronavirus disease 2019 pandemic. RESULTS: A total of 186 participants were randomized. After the induction period, the experimental group had higher global cognitive test scores (Montreal Cognitive Assessment [primary outcome]; 1.75 points [p = .03]) compared with the control group. After induction, experimental group participants with normal cognition had higher language-based executive function (semantic fluency test [secondary outcome]; 2.56 points [p = .03]). At the end of the maintenance period, the experimental group of mild cognitive impairment subjects had higher encoding function (Craft Story immediate recall test [secondary outcome]; 2.19 points [p = .04]). Measure of emotional well-being improved in both control and experimental groups. Resting-state functional magnetic resonance imaging showed that the experimental group had increased connectivity within the dorsal attention network relative to the control group (p = .02), but the sample size was limited. DISCUSSION AND IMPLICATIONS: Providing frequent stimulating conversational interactions via the internet could be an effective home-based dementia risk-reduction strategy against social isolation and cognitive decline. CLINICAL TRIALS REGISTRATION NUMBER: NCT02871921.


Asunto(s)
Disfunción Cognitiva , Demencia , Humanos , Anciano , Disfunción Cognitiva/psicología , Cognición , Función Ejecutiva
7.
Pac Symp Biocomput ; 29: 187-200, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38160279

RESUMEN

Mild cognitive impairment (MCI) represents the early stage of dementia including Alzheimer's disease (AD) and is a crucial stage for therapeutic interventions and treatment. Early detection of MCI offers opportunities for early intervention and significantly benefits cohort enrichment for clinical trials. Imaging and in vivo markers in plasma and cerebrospinal fluid biomarkers have high detection performance, yet their prohibitive costs and intrusiveness demand more affordable and accessible alternatives. The recent advances in digital biomarkers, especially language markers, have shown great potential, where variables informative to MCI are derived from linguistic and/or speech and later used for predictive modeling. A major challenge in modeling language markers comes from the variability of how each person speaks. As the cohort size for language studies is usually small due to extensive data collection efforts, the variability among persons makes language markers hard to generalize to unseen subjects. In this paper, we propose a novel subject harmonization tool to address the issue of distributional differences in language markers across subjects, thus enhancing the generalization performance of machine learning models. Our empirical results show that machine learning models built on our harmonized features have improved prediction performance on unseen data. The source code and experiment scripts are available at https://github.com/illidanlab/subject_harmonization.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biología Computacional , Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Biomarcadores , Progresión de la Enfermedad
8.
J Multidiscip Healthc ; 16: 3663-3673, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38046050

RESUMEN

Objective: This study describes strategies for the recruitment of socially isolated older old Black individuals to participate in the "Internet-based conversational engagement clinical trial (I-CONECT)" (Clinical Trial.gov: NCT02871921) and lessons learned in this critical population segment. Methods: Best practice strategies to recruit the target population included mass mailings, advertisements, and direct community outreach, including the collaboration with a community group created to reach Black individuals interested in research participation. We also made protocol changes to measure recruitment criteria for older old Black adults more accurately and to increase their participation. Results: Descriptive data related to the challenges and successes in recruiting Black participants compared to the White participants is presented. The primary site contacted 17,523 primarily White potential participants and enrolled/randomized 145 White and 2 Asian/mixed race participants (0.8%). The Midwest site contacted 12,141 Black potential participants and enrolled/randomized 39 (0.3%) participants. Discussion: While best practices were employed, several factors complicated recruitment, including the need to adjust recruitment criteria, navigate regional regulations, and respect diverse community preferences. Conclusion: Older old African Americans are reachable and willing to participate in research when considering their beliefs and practices, influenced by their community and experience.

9.
Alzheimers Dement (N Y) ; 9(4): e12435, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38023621
10.
Front Neurol ; 14: 1258216, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900599

RESUMEN

Background: Frequent digital monitoring of cognition is a promising approach for assessing endpoints in prevention and treatment trials of Alzheimer's disease and related dementias (ADRD). This study evaluated the feasibility of the MIND GamePack© for recurrent semi-passive assessment of cognition across a longitudinal interval. Methods: The MIND GamePack consists of four iPad-based games selected to be both familiar and enjoyable: Word Scramble, Block Drop, FreeCell, and Memory Match. Participants were asked to play 20 min/day for 5 days (100 min) for 4 months. Feasibility of use by older adults was assessed by measuring gameplay time and game performance. We also evaluated compliance through semi-structured surveys. A linear generalized estimating equation (GEE) model was used to analyze changes in gameplay time, and a regression tree model was employed to estimate the days it took for game performance to plateau. Subjective and environmental factors associated with gameplay time and performance were examined, including daily self-reported questions of memory and thinking ability, mood, sleep, energy, current location, and distractions prior to gameplay. Results: Twenty-six cognitively-unimpaired older adults participated (mean age ± SD = 71.9 ± 8.6; 73% female). Gameplay time remained stable throughout the 4-months, with an average compliance rate of 91% ± 11% (1946 days of data across all participants) and weekly average playtime of 210 ± 132 min per participant. We observed an initial learning curve of improving game performance which on average, plateaued after 22-39 days, depending on the game. Higher levels of self-reported memory and thinking ability were associated with more gameplay time and sessions. Conclusion: MIND GamePack is a feasible and well-designed semi-passive cognitive assessment platform which may provide complementary data to traditional neuropsychological testing in research on aging and dementia.

11.
Med Care Res Rev ; : 10775587231207668, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37872791

RESUMEN

Home- and community-based services (HCBS) users, on average, experience hospitalizations more frequently than nursing facility residents. However, little is known about state-level variation in such adverse events among these groups. Using 2018 Medicare and Medicaid claims for dual-eligible beneficiaries with Alzheimer's disease and related dementias, we described hospitalization and emergency department (ED) visit rates among HCBS users and nursing facility residents and observed substantial state-level variation. In addition, consistent with prior evidence, we found more frequent hospitalizations and ED visits among HCBS users than nursing facility residents. The magnitude of this difference varied considerably across states, and the degree of variation was greatest among beneficiaries with six or more comorbid conditions. Our findings represent a crucial initial exploration of the state-level variation in adverse events among HCBS users and nursing facility residents, paving the way for further investigations into factors that contribute to this variability.

12.
Alzheimer Dis Assoc Disord ; 37(4): 328-334, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37862614

RESUMEN

BACKGROUND: Early detection is necessary for the treatment of dementia. Computerized testing has become more widely used in clinical trials; however, it is unclear how sensitive these measures are to early signs of neurodegeneration. We investigated the use of the NIH Toolbox-Cognition (NIHTB-CB) and Cogstate-Brief computerized neuropsychological batteries in the identification of mild cognitive impairment (MCI) versus healthy older adults [healthy control (HC)] and amnestic (aMCI) versus nonamnestic MCI (naMCI). Exploratory analyses include investigating potential racial differences. METHODS: Two hundred six older adults were diagnosed as aMCI (n = 58), naMCI (n = 15), or cognitively healthy (HC; n = 133). RESULTS: The NIH Toolbox-CB subtests of Flanker, Picture Sequence Memory, and Picture Vocabulary significantly differentiated MCI from HC. Further, subtests from both computerized batteries differentiated patients with aMCI from those with naMCI. Although the main effect of race differences was noted on tests and in diagnostic groups was significant, there were no significant race-by-test interactions. CONCLUSIONS: Computer-based subtests vary in their ability to help distinguish MCI subtypes, though these tests provide less expensive and easier-to-administer clinical screeners to help identify patients early who may qualify for more comprehensive evaluations. Further work is needed, however, to refine computerized tests to achieve better precision in distinguishing impairment subtypes.


Asunto(s)
Amnesia , Disfunción Cognitiva , Humanos , Anciano , Amnesia/diagnóstico , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/psicología , Cognición , Pruebas Neuropsicológicas
13.
J Aging Health ; : 8982643231199806, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37800686

RESUMEN

Introduction: Emotional functioning in older adults is influenced by normal aging and cognitive impairment, likely heterogeneous across positive versus negative aspects of emotional functioning. Little is known about positive emotional experiences at the early stages of cognitive impairment. Methods: We assessed different aspects of emotional functioning among 448 participants aged 65+ (Normal Control (NC) = 276, Mild Cognitive Impairment (MCI) = 103, and mild dementia of the Alzheimer type (mild DAT) = 69) and tested moderators. Results: Compared to NC, older adults with MCI and mild DAT have maintained many positive aspects of emotional functioning, despite higher levels of negative affect, sadness, and loneliness. Among the oldest-old, the mild DAT group experienced higher fear and lower self-efficacy. Discussion: Older adults at early stages of cognitive impairment can experience positive aspects of emotional functioning, such as positive affect, purpose, and life satisfaction, all of which are important buildable psychological resources for coping.

14.
J Appl Gerontol ; 42(12): 2313-2324, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37518906

RESUMEN

In this study, we examined associations of social isolation and loneliness with cognitive impairment among older adults from a Rust Belt region in Southwest Pennsylvania. We used data from the population-based Monongahela-Youghiogheny Healthy Aging Team (MYHAT) study. We found that (a) 11 items combined into two reliable composites of social isolation and loneliness; (b) unique to this study, providing unpaid help to others was an indicator of reduced social isolation; (c) social isolation and loneliness were positively associated with cognitive impairment; and (d) these associations were appreciably attenuated by general health and physical functional status and depressive symptoms, respectively. We concluded that social isolation and loneliness are differentially associated with older adults' cognitive health, and that their effects might operate through separate pathways. Approaches to address social isolation and loneliness should consider the community context and its implications for older adults' cognitive health.


Asunto(s)
Disfunción Cognitiva , Envejecimiento Saludable , Humanos , Anciano , Soledad/psicología , Aislamiento Social/psicología , Disfunción Cognitiva/psicología , Pennsylvania/epidemiología
15.
PLoS One ; 18(6): e0286812, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37289845

RESUMEN

BACKGROUND: Outcome measures available for use in Alzheimer's disease (AD) clinical trials are limited in ability to detect gradual changes. Measures of everyday function and cognition assessed unobtrusively at home using embedded sensing and computing generated "digital biomarkers" (DBs) have been shown to be ecologically valid and to improve efficiency of clinical trials. However, DBs have not been assessed for their relationship to AD neuropathology. OBJECTIVES: The goal of the current study is to perform an exploratory examination of possible associations between DBs and AD neuropathology in an initially cognitively intact community-based cohort. METHODS: Participants included in this study were ≥65 years of age, living independently, of average health for age, and followed until death. Algorithms, run on the continuously-collected passive sensor data, generated daily metrics for each DB: cognitive function, mobility, socialization, and sleep. Fixed postmortem brains were evaluated for neurofibrillary tangles (NFTs) and neuritic plaque (NP) pathology and staged by Braak and CERAD systems in the context of the "ABC" assessment of AD-associated changes. RESULTS: The analysis included a total of 41 participants (M±SD age at death = 92.2±5.1 years). The four DBs showed consistent patterns relative to both Braak stage and NP score severity. Greater NP severity was correlated with the DB composite and reduced walking speed. Braak stage was associated with reduced computer use time and increased total time in bed. DISCUSSION: This study provides the first data showing correlations between DBs and neuropathological markers in an aging cohort. The findings suggest continuous, home-based DBs may hold potential to serve as behavioral proxies that index neurodegenerative processes.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Encéfalo/patología , Ovillos Neurofibrilares/patología , Cognición , Envejecimiento/patología , Placa Amiloide/patología
16.
Smart Health (Amst) ; 282023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37065441

RESUMEN

Social isolation has become a growing public health concern in older adults and older adults with mild cognitive impairment. Coping strategies must be developed to increase social contact for socially isolated older adults. In this paper, we explored the conversational strategy between trained conversation moderators and socially isolated adults during a conversational engagement clinical trial (Clinicaltrials.gov: NCT02871921). We carried out structural learning and causality analysis to investigate the conversation strategies used by the trained moderators to engage socially isolated adults in the conversation and the causal effects of the strategy on engagement. Causal relations and effects were inferred between participants' emotions, the dialogue strategies used by moderators, and participants' following emotions. The results found in this paper may be used to support the development of cost-efficient, trustworthy AI- and/or robot-based platform to promote conversational engagement for older adults to address the challenges in social interaction.

17.
Pac Symp Biocomput ; 28: 7-18, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36540960

RESUMEN

Mild cognitive impairment is the prodromal stage of Alzheimer's disease. Its detection has been a critical task for establishing cohort studies and developing therapeutic interventions for Alzheimer's. Various types of markers have been developed for detection. For example, imaging markers from neuroimaging have shown great sensitivity, while its cost is still prohibitive for large-scale screening of early dementia. Recent advances from digital biomarkers, such as language markers, have provided an accessible and affordable alternative. While imaging markers give anatomical descriptions of the brain, language markers capture the behavior characteristics of early dementia subjects. Such differences suggest the benefits of auxiliary information from the imaging modality to improve the predictive power of unimodal predictive models based on language markers alone. However, one significant barrier to the joint analysis is that in typical cohorts, there are only very limited subjects that have both imaging and language modalities. To tackle this challenge, in this paper, we develop a novel crossmodal augmentation tool, which leverages auxiliary imaging information to improve the feature space of language markers so that a subject with only language markers can benefit from imaging information through the augmentation. Our experimental results show that the multi-modal predictive model trained with language markers and auxiliary imaging information significantly outperforms unimodal predictive models.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Biología Computacional , Disfunción Cognitiva/diagnóstico por imagen , Enfermedad de Alzheimer/diagnóstico por imagen , Neuroimagen , Lenguaje , Progresión de la Enfermedad
18.
J Gerontol A Biol Sci Med Sci ; 78(4): 663-672, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36208464

RESUMEN

BACKGROUND: We assessed 10-year longitudinal associations between late-life social networks and incidence of all-cause dementia (ACD), Alzheimer's disease (AD), and vascular dementia (VaD) in Japanese-American men. METHODS: We prospectively analyzed, from baseline (1991-1993) through 1999-2000, 2636 initially nondemented Kuakini Honolulu-Asia Aging Study participants who remained dementia-free during the first 3 years of follow-up. Global cognition was evaluated by the Cognitive Abilities Screening Instrument (CASI); depressive symptoms by the 11-item Center for Epidemiologic Studies Depression (CES-D) Scale; and social networks by the Lubben Social Network Scale (LSNS). Median split of LSNS scores defined weak/strong social network groups. A panel of neurologists and geriatricians diagnosed and classified dementia; AD and VaD diagnoses comprised cases in which AD or VaD, respectively, were considered the primary cause of dementia. RESULTS: Median (range) baseline age was 77 (71-93) years. Participants with weak (LSNS score ≤29) versus strong (>29) social networks had higher age-adjusted incidence (in person-years) of ACD (12.6 vs. 8.7; p = .014) and AD (6.7 vs. 4.0; p = .007) but not VaD (2.4 vs. 1.4; p = .15). Kaplan-Meier curves showed a lower likelihood of survival free of ACD (log-rank p < .0001) and AD (p = .0006) for men with weak networks. In Cox proportional hazards models adjusting for age, education, APOE ɛ4, prevalent stroke, depressive symptoms, and CASI score (all at baseline), weak networks predicted increased incidence of ACD (hazard ratio [HR] = 1.52, p = .009) and AD (HR = 1.67, p = .014) but not VaD (p > .2). CONCLUSION: Weak social networks may heighten the risk of dementia and AD, underscoring the need to promote social connectedness in older adults.


Asunto(s)
Enfermedad de Alzheimer , Demencia Vascular , Masculino , Humanos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/diagnóstico , Envejecimiento , Asia , Escolaridad , Factores de Riesgo
19.
J Neuropathol Exp Neurol ; 82(1): 57-70, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-36343095

RESUMEN

Postmortem (PM) magnetic resonance imaging (MRI) can serve as a bridge between in vivo imaging and histology by connecting MRI observed macrostructural findings to histological staining and microstructural changes. Data were acquired from 20 formalin-fixed brains including T2, T1, PD, and T2*-weighted images of left hemispheres and 6-mm-thick coronal slices. Tissue slices were bisected, aligned to MR images and used to guide histological sampling. Markers of myelin and oligodendroglia alterations were semiquantitatively rated and compared within white matter hyperintensities (WMHs) and normal-appearing white matter. Tissue priors were created from 3T in vivo data and used to guide segmentation of WMH. PM WMH and hemisphere volumes were compared to volumes derived from in vivo data. PM T2 WMH and T1 hemisphere volumes were correlated with in vivo 3T FLAIR WMH and T1 hemisphere volumes. WMH showed significant myelin loss, decreased GFAP expression and increased vimentin expression. MR-visible perivascular spaces and cortical microvascular lesions were successfully captured on histopathological sections. PM MRI can quantify cerebrovascular disease burden and guide tissue sampling, allowing for more comprehensive characterization of cerebrovascular disease that may be used to study etiologies of age-related cognitive change.


Asunto(s)
Trastornos Cerebrovasculares , Sustancia Blanca , Humanos , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Trastornos Cerebrovasculares/patología , Sustancia Blanca/patología , Vaina de Mielina
20.
Alzheimers Dement (Amst) ; 14(1): e12372, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36381558

RESUMEN

Introduction: Examining the emotional functioning of individuals with mild cognitive impairment (MCI) could help describe their cognitive status and inform the development of interventions. This study compared the emotional characteristics of socially isolated older adults with and without MCI. Methods: We used baseline data from the Internet-based Conversational Engagement Clinical Trial. Emotional characteristics were assessed with the National Institutes of Health Toolbox Emotion Battery (NIHTB-EB). MCI status was determined with a consensus clinical diagnosis. Results: This study included 163 participants (mean age = 81.2 years, non-Hispanic Black = 20.7%, MCI = 52.8%). MCI was associated with higher negative affect and lower psychological well-being. Non-Hispanic Black participants scored lower in sadness, higher in positive affect, and higher in meaning and purpose than non-Hispanic White participants. Conclusion: Older adults with MCI experience more negative emotions and worse psychological well-being than those with normal cognition. The NIHTB-EB appears to be a sensitive tool to detect emotional characteristics associated with cognitive decline.

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