RESUMEN
Aging is characterized by a progressive loss of brain volume at an estimated rate of 5% per decade after age 40. While these morphometric changes, especially those affecting gray matter and atrophy of the temporal lobe, are predictors of cognitive performance, the strong association with aging obscures the potential parallel, but more specific role, of individual subject physiology. Here, we studied a cohort of 554 human subjects who were monitored using structural MRI scans and blood immune protein concentrations. Using machine learning, we derived a cytokine clock (CyClo), which predicted age with good accuracy (Mean Absolute Error = 6 y) based on the expression of a subset of immune proteins. These proteins included, among others, Placenta Growth Factor (PLGF) and Vascular Endothelial Growth Factor (VEGF), both involved in angiogenesis, the chemoattractant vascular cell adhesion molecule 1 (VCAM-1), the canonical inflammatory proteins interleukin-6 (IL-6) and tumor necrosis factor alpha (TNFα), the chemoattractant IP-10 (CXCL10), and eotaxin-1 (CCL11), previously involved in brain disorders. Age, sex, and the CyClo were independently associated with different functionally defined cortical networks in the brain. While age was mostly correlated with changes in the somatomotor system, sex was associated with variability in the frontoparietal, ventral attention, and visual networks. Significant canonical correlation was observed for the CyClo and the default mode, limbic, and dorsal attention networks, indicating that immune circulating proteins preferentially affect brain processes such as focused attention, emotion, memory, response to social stress, internal evaluation, and access to consciousness. Thus, we identified immune biomarkers of brain aging which could be potential therapeutic targets for the prevention of age-related cognitive decline.
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Encéfalo , Factor A de Crecimiento Endotelial Vascular , Humanos , Adulto , Atrofia , Encéfalo/diagnóstico por imagen , Envejecimiento , Investigadores , CitocinasRESUMEN
INTRODUCTION: Lewy body disease (LBD) is a common primary or co-pathology in neurodegenerative syndromes. An alpha-synuclein seed amplification assay (αSyn-SAA) is clinically available, but clinical performance, especially lower sensitivity in amygdala-predominant cases, is not well understood. METHODS: Antemortem CSF from neuropathology-confirmed LBD cases was tested with αSyn-SAA (N = 56). Diagnostic performance and clinicopathological correlations were examined. RESULTS: Similar to prior reports, sensitivity was 100% for diffuse and transitional LBD (9/9), and overall specificity was 96.3% (26/27). Sensitivity was lower in amygdala-predominant (6/14, 42.8%) and brainstem-predominant LBD (1/6, 16.7%), but early spread outside these regions (without meeting criteria for higher stage) was more common in αSyn-SAA-positive cases (6/7, 85.7%) than negative (2/13, 15.4%). DISCUSSION: In this behavioral neurology cohort, αSyn-SAA had excellent diagnostic performance for cortical LBD. In amygdala- and brainstem-predominant cases, sensitivity was lower, but positivity was associated with anatomical spread, suggesting αSyn-SAA detects early LBD progression in these cohorts. HIGHLIGHTS: A cerebrospinal fluid alpha-synuclein assay detects cortical LBD with high sensitivity/specificity. Positivity in prodromal stages of LBD was associated with early cortical spread. The assay provides precision diagnosis of LBD that could support clinical trials. The assay can also identify LBD co-pathology, which may impact treatment responses.
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Autopsia , Enfermedad por Cuerpos de Lewy , Sensibilidad y Especificidad , alfa-Sinucleína , Humanos , alfa-Sinucleína/líquido cefalorraquídeo , Enfermedad por Cuerpos de Lewy/líquido cefalorraquídeo , Enfermedad por Cuerpos de Lewy/patología , Femenino , Masculino , Anciano , Estudios de Cohortes , Amígdala del Cerebelo/patología , Anciano de 80 o más Años , Biomarcadores/líquido cefalorraquídeo , Persona de Mediana EdadRESUMEN
BACKGROUND: Measuring systemic inflammatory markers may improve clinical prognosis and help identify targetable pathways for treatment in patients with autosomal dominant forms of frontotemporal lobar degeneration (FTLD). METHODS: We measured plasma concentrations of IL-6, TNFα and YKL-40 in pathogenic variant carriers (MAPT, C9orf72, GRN) and non-carrier family members enrolled in the ARTFL-LEFFTDS Longitudinal Frontotemporal Lobar Degeneration consortium. We evaluated associations between baseline plasma inflammation and rate of clinical and neuroimaging changes (linear mixed effects models with standardised (z) outcomes). We compared inflammation between asymptomatic carriers who remained clinically normal ('asymptomatic non-converters') and those who became symptomatic ('asymptomatic converters') using area under the curve analyses. Discrimination accuracy was compared with that of plasma neurofilament light chain (NfL). RESULTS: We studied 394 participants (non-carriers=143, C9orf72=117, GRN=62, MAPT=72). In MAPT, higher TNFα was associated with faster functional decline (B=0.12 (0.02, 0.22), p=0.02) and temporal lobe atrophy. In C9orf72, higher TNFα was associated with faster functional decline (B=0.09 (0.03, 0.16), p=0.006) and cognitive decline (B=-0.16 (-0.22, -0.10), p<0.001), while higher IL-6 was associated with faster functional decline (B=0.12 (0.03, 0.21), p=0.01). TNFα was higher in asymptomatic converters than non-converters (ß=0.29 (0.09, 0.48), p=0.004) and improved discriminability compared with plasma NfL alone (ΔR2=0.16, p=0.007; NfL: OR=1.4 (1.03, 1.9), p=0.03; TNFα: OR=7.7 (1.7, 31.7), p=0.007). CONCLUSIONS: Systemic proinflammatory protein measurement, particularly TNFα, may improve clinical prognosis in autosomal dominant FTLD pathogenic variant carriers who are not yet exhibiting severe impairment. Integrating TNFα with markers of neuronal dysfunction like NfL could optimise detection of impending symptom conversion in asymptomatic pathogenic variant carriers and may help personalise therapeutic approaches.
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Demencia Frontotemporal , Degeneración Lobar Frontotemporal , Humanos , Proteína C9orf72/genética , Progresión de la Enfermedad , Demencia Frontotemporal/diagnóstico , Degeneración Lobar Frontotemporal/diagnóstico , Degeneración Lobar Frontotemporal/genética , Degeneración Lobar Frontotemporal/patología , Inflamación , Interleucina-6 , Mutación , Proteínas tau/genética , Factor de Necrosis Tumoral alfaRESUMEN
At present, no research criteria exist for the diagnosis of prodromal behavioural variant frontotemporal dementia (bvFTD), though early detection is of high research importance. Thus, we sought to develop and validate a proposed set of research criteria for prodromal bvFTD, termed 'mild behavioural and/or cognitive impairment in bvFTD' (MBCI-FTD). Participants included 72 participants deemed to have prodromal bvFTD; this comprised 55 carriers of a pathogenic mutation known to cause frontotemporal lobar degeneration, and 17 individuals with autopsy-confirmed frontotemporal lobar degeneration. All had mild behavioural and/or cognitive changes, as judged by an evaluating clinician. Based on extensive clinical workup, the prodromal bvFTD group was divided into a Development Group (n = 22) and a Validation Group (n = 50). The Development Group was selected to be the subset of the prodromal bvFTD group for whom we had the strongest longitudinal evidence of conversion to bvFTD, and was used to develop the MBCI-FTD criteria. The Validation Group was the remainder of the prodromal bvFTD group and was used as a separate sample on which to validate the criteria. Familial non-carriers were included as healthy controls (n = 165). The frequencies of behavioural and neuropsychiatric features, neuropsychological deficits, and social cognitive dysfunction in the prodromal bvFTD Development Group and healthy controls were assessed. Based on sensitivity and specificity analyses, seven core features were identified: apathy without moderate-severe dysphoria, behavioural disinhibition, irritability/agitation, reduced empathy/sympathy, repetitive behaviours (simple and/or complex), joviality/gregariousness, and appetite changes/hyperorality. Supportive features include a neuropsychological profile of impaired executive function or naming with intact orientation and visuospatial skills, reduced insight for cognitive or behavioural changes, and poor social cognition. Three core features or two core features plus one supportive feature are required for the diagnosis of possible MBCI-FTD; probable MBCI-FTD requires imaging or biomarker evidence, or a pathogenic genetic mutation. The proposed MBCI-FTD criteria correctly classified 95% of the prodromal bvFTD Development Group, and 74% of the prodromal bvFTD Validation Group, with a false positive rate of <10% in healthy controls. Finally, the MBCI-FTD criteria were tested on a cohort of individuals with prodromal Alzheimer's disease, and the false positive rate of diagnosis was 11-16%. Future research will need to refine the sensitivity and specificity of these criteria, and incorporate emerging biomarker evidence.
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Enfermedad de Alzheimer , Demencia Frontotemporal , Degeneración Lobar Frontotemporal , Enfermedad de Alzheimer/psicología , Biomarcadores , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/genética , Demencia Frontotemporal/patología , Degeneración Lobar Frontotemporal/patología , Humanos , Pruebas NeuropsicológicasRESUMEN
BACKGROUND: Frontotemporal Dementia (FTD) patients are geographically dispersed and often have behavioral and/or motor deficits that limit access to in-person clinical trials and research. To address these participation barriers, we investigated the feasibility of installing in-home sensor technologies to remotely assess everyday functioning in FTD. METHOD: We aimed to recruit 20 FTD participants with a variety of clinical syndromes, including behavioral variant FTD (bvFTD), primary progressive aphasia (PPA), corticobasal syndrome (CBS), and progressive supranuclear palsy (PSP). We also aimed to enroll a study partner for each participant that lived in the same home to serve as a control. The Collaborative Aging Research Using Technology (CART) platform was installed in participants' homes to collect continuous data for up to two years, using motion sensors, physiological monitoring devices (e.g., scales, sleep sensors), electronic pillboxes, and wearable actigraphs. Computer use and driving patterns were also tracked. Technology was installed either via a study coordinator visit or remotely through video and written instructions, based on schedule and logistics. Participants were asked to complete a weekly Qualtrics survey about time away from home, visitors, and health changes. RESULT: Of the 159 UCSF participants available for recruitment through ALLFTD and other FTD projects, 28% (N = 45) met inclusion criteria. Of those 45, ten were ineligible due to advanced disease severity or relocation to an assisted living facility. A third (36%, N = 17) declined due to overwhelmed study partners (N = 3), declined any subproject participation (N = 7), sensitivity to participant's diagnosis (N = 2), or lack of response (N = 5). Two additional participants were recruited through UCLA's ALLFTD cohort. The platform has been installed in 19 homes (bvFTD: n = 10; PPA: n = 5; CBS/PSP: n = 4). Two homes discontinued due to death or relocation to assisted living facility. Mean data collection is 360 days (max = 527). Of 103 reported technological issues, 92% were resolved without additional home visits, either by phone or email. Participants completed 65% of weekly health questionnaires. CONCLUSIONS: Although there were some recruitment and retention challenges, these findings generally provide preliminary support for the feasibility and sustainability of conducting comprehensive in-home passive data research in FTD.
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Demencia Frontotemporal , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Afasia Progresiva Primaria/diagnóstico , Parálisis Supranuclear Progresiva/diagnóstico , Estudios de Factibilidad , Actividades CotidianasRESUMEN
INTRODUCTION: Empathy relies on fronto-cingular and temporal networks that are selectively vulnerable in behavioral variant frontotemporal dementia (bvFTD). This study modeled when in the disease process empathy changes begin, and how they progress. METHODS: Four hundred thirty-one individuals with asymptomatic genetic FTD (n = 114), genetic and sporadic bvFTD (n = 317), and 163 asymptomatic non-carrier controls were enrolled. In sub-samples, we investigated empathy measured by the informant-based Interpersonal Reactivity Index (IRI) at each disease stage and over time (n = 91), and its correspondence to underlying atrophy (n = 51). RESULTS: Empathic concern (estimate = 4.38, 95% confidence interval [CI] = 2.79, 5.97; p < 0.001) and perspective taking (estimate = 5.64, 95% CI = 3.81, 7.48; p < 0.001) scores declined between the asymptomatic and very mild symptomatic stages regardless of pathogenic variant status. More rapid loss of empathy corresponded with subcortical atrophy. DISCUSSION: Loss of empathy is an early and progressive symptom of bvFTD that is measurable by IRI informant ratings and can be used to monitor behavior in neuropsychiatry practice and treatment trials.
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Empatía , Demencia Frontotemporal , Humanos , Demencia Frontotemporal/diagnóstico , Pruebas Neuropsicológicas , Atrofia , Imagen por Resonancia MagnéticaRESUMEN
OBJECTIVE: There are minimal data directly comparing plasma neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) in aging and neurodegenerative disease research. We evaluated associations of plasma NfL and plasma GFAP with brain volume and cognition in two independent cohorts of older adults diagnosed as clinically normal (CN), mild cognitive impairment (MCI), or Alzheimer's dementia. METHODS: We studied 121 total participants (Cohort 1: n = 50, age 71.6 ± 6.9 years, 78% CN, 22% MCI; Cohort 2: n = 71, age 72.2 ± 9.2 years, 45% CN, 25% MCI, 30% dementia). Gray and white matter volumes were obtained for total brain and broad subregions of interest (ROIs). Neuropsychological testing evaluated memory, executive functioning, language, and visuospatial abilities. Plasma samples were analyzed in duplicate for NfL and GFAP using single molecule array assays (Quanterix Simoa). Linear regression models with structural MRI and cognitive outcomes included plasma NfL and GFAP simultaneously along with relevant covariates. RESULTS: Higher plasma GFAP was associated with lower white matter volume in both cohorts for temporal (Cohort 1: ß = -0.33, p = .002; Cohort 2: ß = -0.36, p = .03) and parietal ROIs (Cohort 1: ß = -0.31, p = .01; Cohort 2: ß = -0.35, p = .04). No consistent findings emerged for gray matter volumes. Higher plasma GFAP was associated with lower executive function scores (Cohort 1: ß = -0.38, p = .01; Cohort 2: ß = -0.36, p = .007). Plasma NfL was not associated with gray or white matter volumes, or cognition after adjusting for plasma GFAP. CONCLUSIONS: Plasma GFAP may be more sensitive to white matter and cognitive changes than plasma NfL. Biomarkers reflecting astroglial pathophysiology may capture complex dynamics of aging and neurodegenerative disease.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedades Neurodegenerativas , Sustancia Blanca , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Biomarcadores , Disfunción Cognitiva/diagnóstico , Función Ejecutiva , Proteína Ácida Fibrilar de la Glía , Humanos , Filamentos Intermedios , Persona de Mediana Edad , Proteínas de Neurofilamentos , Sustancia Blanca/diagnóstico por imagenRESUMEN
OBJECTIVES: The relationship between wisdom and fluid intelligence (Gf) is poorly understood, particularly in older adults. We empirically tested the magnitude of the correlation between wisdom and Gf to help determine the extent of overlap between these two constructs. DESIGN: Cross-sectional study with preregistered hypotheses and well-powered analytic plan (https://osf.io/h3pjx). SETTING: Memory and Aging Center at the University of California San Francisco, located in the USA. PARTICIPANTS: 141 healthy older adults (mean age = 76 years; 56% female). MEASUREMENTS: Wisdom was quantified using a well-validated self-report-based scale (San Diego Wisdom Scale or SD-WISE). Gf was assessed via composite measures of processing speed (Gf-PS) and executive functioning (Gf-EF). The relationships of SD-WISE scores to Gf-PS and Gf-EF were tested in bivariate correlational analyses and multiple regression models adjusted for demographics (age, sex, and education). Exploratory analyses evaluated the relationships between SD-WISE and age, episodic memory performance, and dorsolateral and ventromedial prefrontal cortical volumes on magnetic resonance imaging. RESULTS: Wisdom showed a small, positive association with Gf-EF (r = 0.181 [95% CI 0.016, 0.336], p = .031), which was reduced to nonsignificance upon controlling for demographics, and no association with Gf-PS (r = 0.019 [95% CI -0.179, 0.216], p = .854). Wisdom demonstrated a small, negative correlation with age (r = -0.197 [95% CI -0.351, -0.033], p = .019), but was not significantly related to episodic memory or prefrontal volumes. CONCLUSIONS: Our findings indicate that most of the variance in wisdom (>95%) is unaccounted for by Gf. The independence of wisdom from cognitive functions that reliably show age-associated declines suggests that it may hold unique potential to bolster decision-making, interpersonal functioning, and other everyday activities in older adults.
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Inteligencia , Memoria Episódica , Anciano , Envejecimiento , Cognición , Estudios Transversales , Función Ejecutiva , Femenino , Humanos , MasculinoRESUMEN
Pattern separation, the ability to differentiate new information from previously experienced similar information, is highly sensitive to hippocampal structure and function and declines with age. Functional MRI studies have demonstrated hippocampal hyperactivation in older adults compared to young, with greater task-related activation associated with worse pattern separation performance. The current study was designed to determine whether pattern separation was sensitive to differences in task-free hippocampal cerebral blood flow (CBF) in 130 functionally intact older adults. Given prior evidence that apolipoprotein E e4 (APOE e4) status moderates the relationship between CBF and episodic memory, we predicted a stronger negative relationship between hippocampal CBF and pattern separation in APOE e4 carriers. An interaction between APOE group and right hippocampal CBF was present, such that greater right hippocampal CBF was related to better lure discrimination in noncarriers, whereas the effect reversed directionality in e4 carriers. These findings suggest that neurovascular changes in the medial temporal lobe may underlie memory deficits in cognitively normal older adults who are APOE e4 carriers.
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Apolipoproteína E4 , Hipocampo , Anciano , Envejecimiento , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Circulación Cerebrovascular/fisiología , Hipocampo/fisiología , Humanos , Imagen por Resonancia Magnética , Pruebas Neuropsicológicas , Flujo Sanguíneo Regional , Lóbulo TemporalRESUMEN
OBJECTIVE: To determine the effects of ESRT (an iteratively adapted and tailored MBI) on perceived stress, executive cognitive function, psychosocial well-being (ie, burnout, mindfulness), and pro-inflammatory gene expression in surgical (ESRT-1) and mixed specialty (ESRT-2) PGY-1 volunteers. SUMMARY OF BACKGROUND AND DATA: Tailored MBIs have proven beneficial in multiple high-stress and high-performance populations. In surgeons, tailored MBIs have been shown to be feasible and potentially beneficial, but whether mindfulness-based cognitive training can improve perceived stress, executive function, well-being or physiological distress in surgical and nonsurgical trainees is unknown. METHODS: In 2 small single-institution randomized clinical trials, ESRT, a tailored mindfulness-based cognitive training program, was administered and iteratively adapted for first-year surgical (ESRT-1, 8 weekly, 2-hour classes, n = 44) and mixed specialty (ESRT-2, 6 weekly, 90-minute classes, n = 45) resident trainees. Primary and secondary outcomes were, respectively, perceived stress and executive function. Other prespecified outcomes were burnout (assessed via Maslach Burnout Inventory), mindfulness (assessed via Cognitive Affective Mindfulness Scale - Revised), and pro-inflammatory gene expression (assessed through the leukocyte transcriptome profile "conserved transcriptional response to adversity"). RESULTS: Neither version of ESRT appeared to affect perceived stress. Higher executive function and mindfulness scores were seen in ESRT-1, and lower emotional exhaustion and depersonalization scores in ESRT-2, at pre-/postintervention and/or 50-week follow-up (ESRT-1) or at 32-week follow-up (ESRT-2), compared to controls. Pooled analysis of both trials found ESRT-treated participants had reduced pro-inflammatory RNA expression compared to controls. CONCLUSIONS: This pilot work suggests ESRT can variably benefit executive function, burnout, and physiologic distress in PGY-1 trainees, with potential for tailoring to optimize effects.
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Adaptación Fisiológica , Agotamiento Profesional/prevención & control , Agotamiento Profesional/psicología , Estrés Laboral/patología , Estrés Laboral/prevención & control , Resiliencia Psicológica , Cirujanos/psicología , Adulto , Educación de Postgrado en Medicina , Femenino , Cirugía General/educación , Humanos , Internado y Residencia , Masculino , Proyectos PilotoRESUMEN
METHOD: Clinically normal older adults (52-92 years old) were followed longitudinally for up to 8 years after completing a memory paradigm at baseline [Story Recall Test (SRT)] that assessed delayed recall at 30 min and 1 week. Subsets of the cohort underwent neuroimaging (N = 134, mean age = 75) and neuropsychological testing (N = 178-207, mean ages = 74-76) at annual study visits occurring approximately 15-18 months apart. Mixed-effects regression models evaluated if baseline SRT performance predicted longitudinal changes in gray matter volumes and cognitive composite scores, controlling for demographics. RESULTS: Worse SRT 1-week recall was associated with more precipitous rates of longitudinal decline in medial temporal lobe volumes (p = .037), episodic memory (p = .003), and executive functioning (p = .011), but not occipital lobe or total gray matter volumes (demonstrating neuroanatomical specificity; p > .58). By contrast, SRT 30-min recall was only associated with longitudinal decline in executive functioning (p = .044). CONCLUSIONS: Memory paradigms that capture longer-term recall may be particularly sensitive to age-related medial temporal lobe changes and neurodegenerative disease trajectories. (JINS, 2020, xx, xx-xx).
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Disfunción Cognitiva , Memoria Episódica , Enfermedades Neurodegenerativas , Anciano , Anciano de 80 o más Años , Cognición , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Pruebas Neuropsicológicas , Lóbulo Temporal/diagnóstico por imagenRESUMEN
Many caregivers of patients with neurodegenerative disease experience physical and psychological strain, which is associated with negative health outcomes. Caregiver strain may be partly attributable to negative emotional responses (e.g.of resentment) to the behavioral, cognitive, and physical changes associated with patients' disease. The philosopher Peter Strawson observed that in dealing with people who have neurological impairments, we often choose to suspend such emotional responses, adopting what he labeled the "objective attitude," though this may come at the expense of our relationships with them. In this study, we assessed the mediating effect of caregivers' adoption of the objective attitude on caregiver strain and relationship closeness in the setting of disease progression. Caregivers of patients with neurodegenerative disorders (n = 215) completed the Clinical Dementia Rating, Relationship-Closeness scale, Caregiver Strain Index, and a novel questionnaire assessing the adoption of the objective attitude. A structural equation model assessing associations among these variables demonstrated good fit (χ2 (88)=164.621, p < 0.001; CFI = 0.929, RMSEA = 0.064.) and showed that adoption of the objective attitude mediated the association between disease progression and relationship closeness (total ß= -0.233, 95% CI: -0.351, -0.113; indirect ß= -0.483, 95% CI: -0.602, -0.364; direct ß = 0.250, 95% CI: 0.117, 0.384), but did not mediate the association between disease progression and caregiver strain (total ß = 0.323, 95% CI: 0.234, 0.412; indirect ß = 0.089, 95% CI: -0.027, 0.206; direct ß = 0.153, 95% CI: -0.043, 0.349). For future work, we propose longitudinal measurements of these constructs to test the directionality of associations and consideration of how models for caregiver support can draw upon interdisciplinary insights.
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Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Actitud , Cuidadores , Humanos , Masculino , Encuestas y CuestionariosRESUMEN
INTRODUCTION: Cognitive composite scores offer a means of precisely measuring executive functioning (EF). METHODS: We developed the Uniform Data Set v3.0 EF composite score (UDS3-EF) in 3507 controls from the National Alzheimer's Coordinating Center dataset using item-response theory and applied nonlinear and linear demographic adjustments. The UDS3-EF was validated with other neuropsychological tests and brain magnetic resonance imaging from independent research cohorts using linear models. RESULTS: Final model fit was good-to-excellent: comparative fit index = 0.99; root mean squared error of approximation = 0.057. UDS3-EF scores differed across validation cohorts (controls > mild cognitive impairment > Alzheimer's disease-dementia ≈ behavioral variant frontotemporal dementia; P < 0.001). The UDS3-EF correlated most strongly with other EF tests (ßs = 0.50 to 0.85, Ps < 0.001) and more with frontal, parietal, and temporal lobe gray matter volumes (ßs = 0.18 to 0.33, Ps ≤ 0.004) than occipital gray matter (ß = 0.12, P = 0.04). The total sample needed to detect a 40% reduction in UDS3-EF change (n = 286) was ≈40% of the next best measure (F-words; n = 714). CONCLUSIONS: The UDS3-EF is well suited to quantify EF in research and clinical trials and offers psychometric and practical advantages over its component tests.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Conjuntos de Datos como Asunto , Función Ejecutiva/fisiología , Psicometría , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Encéfalo/patología , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/patología , Femenino , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricosRESUMEN
INTRODUCTION: Biological sex is an increasingly recognized factor driving clinical and structural heterogeneity in Alzheimer's disease, but its role in the behavioral variant of frontotemporal dementia (bvFTD) is unknown. METHODS: We included 216 patients with bvFTD and 235 controls with magnetic resonance imaging (MRI) from a large multicenter cohort. We compared the clinical characteristics and cortical thickness between men and women with bvFTD and controls. We followed the residuals approach to study behavioral and cognitive reserve. RESULTS: At diagnosis, women with bvFTD showed greater atrophy burden in the frontotemporal regions compared to men despite similar clinical characteristics. For a similar amount of atrophy, women demonstrated better-than-expected scores on executive function and fewer changes in apathy, sleep, and appetite than men. DISCUSSION: Our findings suggest that women might have greater behavioral and executive reserve than men, and neurodegeneration must be more severe in women to produce symptoms similar in severity to those in men.
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Atrofia/patología , Función Ejecutiva , Demencia Frontotemporal/diagnóstico , Resiliencia Psicológica , Estudios de Cohortes , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores SexualesRESUMEN
OBJECTIVE: Despite the losses commonly associated with aging, older adults seem to possess particularly preserved emotional regulation. To further understand this phenomenon, the authors examined longitudinal trajectories between age, depressive symptoms, brain structure, and cognition. METHODS: Seven hundred and sixteen functionally intact older adults (age Mâ¯=â¯67.9, 56.8% female), followed longitudinally (visit range: 1-13, Mâ¯=â¯2.5), completed cognitive testing and the Geriatric Depression Scale (GDS). A subset (Nâ¯=â¯327) underwent 3T brain MRI. Mixed-effects linear regression models were conducted controlling for sex, education, and total intracranial volume. RESULTS: There was a significant interaction between age and time on GDS, such that GDS improved with increasing age over time, but attenuated around age 71 (age*time bâ¯=â¯0.10, p <0.001). Fractional anisotropy (FA) and mean diffusivity interacted with age to predict longitudinal changes in GDS (FA: bâ¯=â¯-0.02, pâ¯=â¯0.01; MD: bâ¯=â¯0.03, pâ¯=â¯0.007), such that age-related benefits on GDS were attenuated in those with declining FA. Executive function (EF) and processing speed also interacted with age to predict longitudinal changes in GDS (EF: bâ¯=â¯-0.04, pâ¯=â¯0.03; speed: bâ¯=â¯0.04, pâ¯=â¯0.04). Again, the positive effect of age on GDS attenuated in those with worsening EF and speed. There were no associations with memory, semantic fluency, or gray matter (p values >0.05). CONCLUSION: EF, processing speed, and white matter integrity moderated the longitudinal relationship between age and mood. Previous studies demonstrate the link between positivity and better cognitive control, leading to improved mood in older adults. Our results are not only consistent, but establish a potential neurobiological correlate. Future research further exploring biological mechanisms driving psychological processes may have important therapeutic implications.
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Envejecimiento/psicología , Encéfalo , Cognición/fisiología , Depresión , Regulación Emocional , Optimismo/psicología , Afecto/fisiología , Anciano , Envejecimiento/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Correlación de Datos , Depresión/diagnóstico , Depresión/etiología , Depresión/prevención & control , Función Ejecutiva/fisiología , Femenino , Neuroimagen Funcional/métodos , Neuroimagen Funcional/estadística & datos numéricos , Humanos , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos , Rendimiento Físico Funcional , Psicología PositivaRESUMEN
Frontotemporal dementia refers to a group of progressive neurodegenerative syndromes usually caused by the accumulation of pathological tau or TDP-43 proteins. The effects of these proteins in the brain are complex, and each can present with several different clinical syndromes. Clinical efficacy trials of drugs targeting these proteins must use endpoints that are meaningful to all participants despite the variability in symptoms across patients. There are many candidate clinical measures, including neuropsychological scores and functional measures. Brain imaging is another potentially attractive outcome that can be precisely quantified and provides evidence of disease modification. Most imaging studies in frontotemporal dementia have been cross-sectional, and few have compared longitudinal changes in cortical volume with changes in other measures such as perfusion and white matter integrity. The current study characterized longitudinal changes in 161 patients with three frontotemporal dementia syndromes: behavioural variant frontotemporal dementia (n = 77) and the semantic (n = 45) and non-fluent (n = 39) variants of primary progressive aphasia. Visits included comprehensive neuropsychological and functional assessment, structural MRI (3 T), diffusion tensor imaging, and arterial spin labelled perfusion imaging. The goal was to identify measures that are appropriate as clinical trial outcomes for each group, as well as those that might be appropriate for trials that would include more than one of these groups. Linear mixed effects models were used to estimate changes in each measure, and to examine the correlation between imaging and clinical changes. Sample sizes were estimated based on the observed effects for theoretical clinical trials using bootstrapping techniques to provide 95% confidence intervals for these estimates. Declines in functional and neuropsychological measures, as well as frontal and temporal cortical volumes and white matter microstructure were detected in all groups. Imaging changes were statistically significantly correlated with, and explained a substantial portion of variance in, the change in most clinical measures. Perfusion and diffusion tensor imaging accounted for variation in clinical decline beyond volume alone. Sample size estimates for atrophy and diffusion imaging were comparable to clinical measures. Corpus callosal fractional anisotropy led to the lowest sample size estimates for all three syndromes. These findings provide further guidance on selection of trial endpoints for studies in frontotemporal dementia and support the use of neuroimaging, particularly structural and diffusion weighted imaging, as biomarkers. Diffusion and perfusion imaging appear to offer additional utility for explaining clinical change beyond the variance explained by volume alone, arguing for considering multimodal imaging in treatment trials.
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Determinación de Punto Final/métodos , Demencia Frontotemporal/diagnóstico por imagen , Demencia Frontotemporal/epidemiología , Imagen Multimodal/métodos , Anciano , Estudios Transversales , Imagen de Difusión Tensora/métodos , Imagen de Difusión Tensora/tendencias , Determinación de Punto Final/tendencias , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/tendencias , Masculino , Persona de Mediana Edad , Imagen Multimodal/tendenciasRESUMEN
INTRODUCTION: The Advancing Research and Treatment in Frontotemporal Lobar Degeneration and Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects longitudinal studies were designed to describe the natural history of familial-frontotemporal lobar degeneration due to autosomal dominant mutations. METHODS: We examined cognitive performance, behavioral ratings, and brain volumes from the first time point in 320 MAPT, GRN, and C9orf72 family members, including 102 non-mutation carriers, 103 asymptomatic carriers, 43 mildly/questionably symptomatic carriers, and 72 carriers with dementia. RESULTS: Asymptomatic carriers showed similar scores on all clinical measures compared with noncarriers but reduced frontal and temporal volumes. Those with mild/questionable impairment showed decreased verbal recall, fluency, and Trail Making Test performance and impaired mood and self-monitoring. Dementia was associated with impairment in all measures. All MAPT carriers with dementia showed temporal atrophy, but otherwise, there was no single cognitive test or brain region that was abnormal in all subjects. DISCUSSION: Imaging changes appear to precede clinical changes in familial-frontotemporal lobar degeneration, but specific early clinical and imaging changes vary across individuals.
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Atrofia/patología , Degeneración Lobar Frontotemporal , Predisposición Genética a la Enfermedad , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Pruebas Neuropsicológicas/estadística & datos numéricos , Proteína C9orf72/genética , Femenino , Degeneración Lobar Frontotemporal/genética , Degeneración Lobar Frontotemporal/patología , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Progranulinas/genética , Lóbulo Temporal/patología , Proteínas tau/genéticaRESUMEN
INTRODUCTION: Identifying clinical measures that track disease in the earliest stages of frontotemporal lobar degeneration (FTLD) is important for clinical trials. Familial FTLD provides a unique paradigm to study early FTLD. Executive dysfunction is a clinically relevant hallmark of FTLD and may be a marker of disease progression. METHODS: Ninety-three mutation carriers with no symptoms or minimal/questionable symptoms (MAPT, n = 31; GRN, n = 28; C9orf72, n = 34; Clinical Dementia Rating scale plus NACC FTLD Module < 1) and 78 noncarriers enrolled through Advancing Research and Treatment in Frontotemporal Lobar Degeneration/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects studies completed the Executive Abilities: Measures and Instruments for Neurobehavioral Evaluation and Research (NIH-EXAMINER) and the UDS neuropsychological battery. Linear mixed-effects models were used to identify group differences in cognition at baseline and longitudinally. We examined associations between cognition, clinical functioning, and magnetic resonance imaging volumes. RESULTS: NIH-EXAMINER scores detected baseline and differences in slopes between carriers and noncarriers, even in carriers with a baseline Clinical Dementia Rating scale plus NACC FTLD Module = 0. NIH-EXAMINER declines were associated with worsening clinical symptoms and brain volume loss. DISCUSSION: The NIH-EXAMINER is sensitive to cognitive changes in presymptomatic familial FTLD and is a promising surrogate endpoint.
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Progresión de la Enfermedad , Función Ejecutiva/fisiología , Demencia Frontotemporal , Pruebas Neuropsicológicas/estadística & datos numéricos , Biomarcadores , Proteína C9orf72/genética , Femenino , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/genética , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , MutaciónRESUMEN
INTRODUCTION: Some models of therapy for neurodegenerative diseases envision starting treatment before symptoms develop. Demonstrating that such treatments are effective requires accurate knowledge of when symptoms would have started without treatment. Familial frontotemporal lobar degeneration offers a unique opportunity to develop predictors of symptom onset. METHODS: We created dementia risk scores in 268 familial frontotemporal lobar degeneration family members by entering covariate-adjusted standardized estimates of brain atrophy into a logistic regression to classify asymptomatic versus demented participants. The score's predictive value was tested in a separate group who were followed up longitudinally (stable vs. converted to dementia) using Cox proportional regressions with dementia risk score as the predictor. RESULTS: Cross-validated logistic regression achieved good separation of asymptomatic versus demented (accuracy = 90%, SE = 0.06). Atrophy scores predicted conversion from asymptomatic or mildly/questionably symptomatic to dementia (HR = 1.51, 95% CI: [1.16,1.98]). DISCUSSION: Individualized quantification of baseline brain atrophy is a promising predictor of progression in asymptomatic familial frontotemporal lobar degeneration mutation carriers.
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Atrofia/patología , Demencia Frontotemporal , Predisposición Genética a la Enfermedad , Mutación/genética , Pruebas Neuropsicológicas/estadística & datos numéricos , Encéfalo/patología , Proteína C9orf72/genética , Femenino , Demencia Frontotemporal/diagnóstico por imagen , Demencia Frontotemporal/genética , Humanos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Progranulinas/genética , Proteínas tau/genéticaRESUMEN
The default mode network (DMN) supports memory functioning and may be sensitive to preclinical Alzheimer's pathology. Little is known, however, about the longitudinal trajectory of this network's intrinsic functional connectivity (FC). In this study, we evaluated longitudinal FC in 111 cognitively normal older human adults (ages 49-87, 46 women/65 men), 92 of whom had at least three task-free fMRI scans (n = 353 total scans). Whole-brain FC and three DMN subnetworks were assessed: (1) within-DMN, (2) between anterior and posterior DMN, and (3) between medial temporal lobe network and posterior DMN. Linear mixed-effects models demonstrated significant baseline age × time interactions, indicating a nonlinear trajectory. There was a trend toward increasing FC between ages 50-66 and significantly accelerating declines after age 74. A similar interaction was observed for whole-brain FC. APOE status did not predict baseline connectivity or change in connectivity. After adjusting for network volume, changes in within-DMN connectivity were specifically associated with changes in episodic memory and processing speed but not working memory or executive functions. The relationship with processing speed was attenuated after covarying for white matter hyperintensities (WMH) and whole-brain FC, whereas within-DMN connectivity remained associated with memory above and beyond WMH and whole-brain FC. Whole-brain and DMN FC exhibit a nonlinear trajectory, with more rapid declines in older age and possibly increases in connectivity early in the aging process. Within-DMN connectivity is a marker of episodic memory performance even among cognitively healthy older adults.SIGNIFICANCE STATEMENT Default mode network and whole-brain connectivity, measured using task-free fMRI, changed nonlinearly as a function of age, with some suggestion of early increases in connectivity. For the first time, longitudinal changes in DMN connectivity were shown to correlate with changes in episodic memory, whereas volume changes in relevant brain regions did not. This relationship was not accounted for by white matter hyperintensities or mean whole-brain connectivity. Functional connectivity may be an early biomarker of changes in aging but should be used with caution given its nonmonotonic nature, which could complicate interpretation. Future studies investigating longitudinal network changes should consider whole-brain changes in connectivity.