711 research outputs found
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Utilization of cognitive support in episodic free recall as a function of apolipoprotein E and vitamin B12 or folate among adults aged 75 years and older
Apolipoprotein E (APOE), vitamin B12, and folate were examined in relation to free recall among 167 community-based older adults. Cognitive support at encoding and retrieval was also taken into account. Participants were classified as APOE e4 or non-e4 allele carriers and as either low or normal vitamin B12 or folate status. A significant association was identified between low vitamin B12 and the e4 genotype in respect to free recall, but only in circumstances of low cognitive support. This result remained after removing dementia cases that occurred up to 6 years after testing. A similar, but nonsignificant, trend was evident in relation to folate. The research is discussed with reference to vulnerability models and genetic influences on brain reserves
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The European Prevention of Alzheimer's Dementia (EPAD) Longitudinal Cohort Study: Baseline Data Release V500.0.
BACKGROUND: The European Prevention of Alzheimer's Dementia (EPAD) Programme is a pan-European project whose objective is to deliver a platform, adaptive, Phase 2 proof of concept (PoC) trial for the secondary prevention of Alzheimer's dementia. A component of this platform is the Longitudinal Cohort Study (LCS) which acts as a readiness cohort for the PoC Trial as well as generating data for disease modelling work in the preclinical and prodromal phases of Alzheimer's dementia. OBJECTIVES: The first data wave has been collected, quality checked, released and now available for analysis to answer numerous research questions. Here we describe the results from key variables in the EPAD LCS with the objective of using these results to compliment analyses of these data in the future. DESIGN: EPAD LCS is a cohort study whose primary objective is as a readiness cohort for the EPAD PoC Trial. As such recruitment is not capped at any particular number but will continue to facilitate delivery of the EPAD PoC Trial. Research Participants are seen annually (with an additional 6 month visit in the first year). SETTING: The EPAD Trial Delivery Network comprises currently 21 centres across Europe. PARTICIPANTS: Research participants are included if they are over 50 years old and do not have a diagnosis of dementia. MEASUREMENTS: All research participants undergo multiple assessments to fully characterise the biology of Alzheimer's disease and relate this to risk factors (both fixed and modifiable) and biomarker expression of disease through brain imaging, fluid samples (CSF, blood, urine and saliva), cognitive performance, functional abilities and neuropsychiatric symptomatology. RESULTS: V500.0 represents the first 500 research participants baselined into EPAD LCS. The mean age was 66.4 (SD=6.7) and 47.8% were male. The data was split for presentation into 4 groups: [1] CDR=0 and Amyloid + (preclinical AD), [2] CDR=0 and Amyloid -, [3] CDR=0.5 and Amyloid + (prodromal AD) and [4] CDR=0.5 and Amyloid -. CONCLUSIONS: The EPAD LCS is achieving its primary objective of trial readiness and the structured approach to data release as manifest by this first data release of V500.0 will assist researchers to describe and compare their findings as well as in systematic reviews and meta-analyses. It is anticipated given current recruitment rates that V1500.0 data release will take place in Autumn 2019. V500.1 (when the 1 year follow up is completed on the V500.0 (sub)cohort will be in Autumn 2019 also.IMI Fundin
Occurrence of medical co-morbidity in mild cognitive impairment: implications for generalisation of MCI research
Background: diagnosis of mild cognitive impairment (MCI) typically excludes individuals with medical co-morbidity. Interest in MCI screening raises the questions of what are the best criteria to identify a representative sample and what factors are associated with MCI progression to dementia
Alzheimer's disease
In this Seminar, we highlight the main developments in the field of Alzheimer's disease. The most recent data indicate that, by 2050, the prevalence of dementia will double in Europe and triple worldwide, and that estimate is 3 times higher when based on a biological (rather than clinical) definition of Alzheimer's disease. The earliest phase of Alzheimer's disease (cellular phase) happens in parallel with accumulating amyloid β, inducing the spread of tau pathology. The risk of Alzheimer's disease is 60-80% dependent on heritable factors, with more than 40 Alzheimer's disease-associated genetic risk loci already identified, of which the APOE alleles have the strongest association with the disease. Novel biomarkers include PET scans and plasma assays for amyloid β and phosphorylated tau, which show great promise for clinical and research use. Multidomain lifestyle-based prevention trials suggest cognitive benefits in participants with increased risk of dementia. Lifestyle factors do not directly affect Alzheimer's disease pathology, but can still contribute to a positive outcome in individuals with Alzheimer's disease. Promising pharmacological treatments are poised at advanced stages of clinical trials and include anti-amyloid β, anti-tau, and anti-inflammatory strategies
Insulin levels are decreased in the cerebrospinal fluid of women with prodomal Alzheimer's disease
Previous studies have failed to reach consensus on insulin levels in cerebrospinal fluid of Alzheimer's disease (AD) patients and on its relation to pathological features. We performed a new analysis in patients at different stages of AD, and investigated the relationship of insulin levels with biochemical disease markers and with cognitive score. We included 99 patients from our Memory Clinic (Karolinska University Hospital, Sweden), including: 27 patients with mild AD, 13 that progressed from mild cognitive impairment (MCI) to AD in two years time, 26 with MCI stable after two years, and 33 with subjective cognitive impairment. Insulin was significantly decreased in the cerebrospinal fluid of both women and men with mild AD. Insulin deficits were seen in women belonging to both MCI groups, suggesting that this occurs earlier than in men. Insulin was positively associated with amyloid-β 1-42 (Aβ1-42) levels and cognitive score. Furthermore, total-tau/(Aβ1-42*insulin) ratio showed strikingly better sensitivity and specificity than the total-tau/Aβ1-42 ratio for early AD diagnosis in women
Development of a Cognitive Training Support Programme for prevention of dementia and cognitive decline in at-risk older adults
BackgroundEvidence for the beneficial effects of cognitive training on cognitive function and daily living activities is inconclusive. Variable study quality and design does not allow for robust comparisons/meta-analyses of different cognitive training programmes. Fairly low adherence to extended cognitive training interventions in clinical trials has been reported.AimsThe aim of further developing a Cognitive Training Support Programme (CTSP) is to supplement the Computerised Cognitive Training (CCT) intervention component of the multimodal Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER), which is adapted to different cultural, regional and economic settings within the Word-Wide FINGERS (WW-FINGERS) Network. The main objectives are to improve adherence to cognitive training through a behaviour change framework and provide information about cognitive stimulation, social engagement and lifestyle risk factors for dementia.MethodsSix CTSP sessions were re-designed covering topics including (1) CCT instructions and tasks, (2) Cognitive domains: episodic memory, executive function and processing speed, (3) Successful ageing and compensatory strategies, (4) Cognitive stimulation and engagement, (5) Wellbeing factors affecting cognition (e.g., sleep and mood), (6) Sensory factors. Session content will be related to everyday life, with participant reflection and behaviour change techniques incorporated, e.g., strategies, goal-setting, active planning to enhance motivation, and adherence to the CCT and in relevant lifestyle changes.ConclusionsThrough interactive presentations promoting brain health, the programme provides for personal reflection that may enhance capability, opportunity and motivation for behaviour change. This will support adherence to the CCT within multidomain intervention trials. Efficacy of the programme will be evaluated through participant feedback and adherence metrics
Age-related differences in the functional topography of the locus coeruleus and their implications for cognitive and affective functions
The locus coeruleus (LC) is an important noradrenergic nucleus that has recently attracted a lot of attention because of its emerging role in cognitive and psychiatric disorders. Although previous histological studies have shown that the LC has heterogeneous connections and cellular features, no studies have yet assessed its functional topography in vivo, how this heterogeneity changes over aging, and whether it is associated with cognition and mood. Here, we employ a gradient-based approach to characterize the functional heterogeneity in the organization of the LC over aging using 3T resting-state fMRI in a population-based cohort aged from 18 to 88 years of age (Cambridge Centre for Ageing and Neuroscience cohort, n=618). We show that the LC exhibits a rostro-caudal functional gradient along its longitudinal axis, which was replicated in an independent dataset (Human Connectome Project [HCP] 7T dataset, n=184). Although the main rostro-caudal direction of this gradient was consistent across age groups, its spatial features varied with increasing age, emotional memory, and emotion regulation. More specifically, a loss of rostral-like connectivity, more clustered functional topography, and greater asymmetry between right and left LC gradients was associated with higher age and worse behavioral performance. Furthermore, participants with higher-than-normal Hospital Anxiety and Depression Scale (HADS) ratings exhibited alterations in the gradient as well, which manifested in greater asymmetry. These results provide an in vivo account of how the functional topography of the LC changes over aging, and imply that spatial features of this organization are relevant markers of LC-related behavioral measures and psychopathology
Age-related differences in the functional topography of the locus coeruleus and their implications for cognitive and affective functions
The locus coeruleus (LC) is an important noradrenergic nucleus that has recently attracted a lot of attention because of its emerging role in cognitive and psychiatric disorders. Although previous histological studies have shown that the LC has heterogeneous connections and cellular features, no studies have yet assessed its functional topography in vivo, how this heterogeneity changes over aging, and whether it is associated with cognition and mood. Here, we employ a gradient-based approach to characterize the functional heterogeneity in the organization of the LC over aging using 3T resting-state fMRI in a population-based cohort aged from 18 to 88 years of age (Cambridge Centre for Ageing and Neuroscience cohort, n=618). We show that the LC exhibits a rostro-caudal functional gradient along its longitudinal axis, which was replicated in an independent dataset (Human Connectome Project [HCP] 7T dataset, n=184). Although the main rostrocaudal direction of this gradient was consistent across age groups, its spatial features varied with increasing age, emotional memory, and emotion regulation. More specifically, a loss of rostral-like connectivity, more clustered functional topography, and greater asymmetry between right and left LC gradients was associated with higher age and worse behavioral performance. Furthermore, participants with higher-than-normal Hospital Anxiety and Depression Scale (HADS) ratings exhibited alterations in the gradient as well, which manifested in greater asymmetry. These results provide an in vivo account of how the functional topography of the LC changes over aging, and imply that spatial features of this organization are relevant markers of LC-related behavioral measures and psychopathology. © Veréb et al
Education-Based Cutoffs for Cognitive Screening of Alzheimer’s Disease
Introduction: The educational background and size of the elderly population are undergoing significant changes in Finland during the 2020s. A similar process is likely to occur also in several European countries. For cognitive screening of early Alzheimer’s disease (AD), using outdated norms and cutoff scores may negatively affect clinical accuracy. The aim of the present study was to examine the effects of education, age, and gender on the Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological battery (CERAD-nb) in a large register-based, clinical sample of patients with mild AD and nondemented at-risk persons from the general population (controls) and to examine whether corrected cutoff scores would increase the accuracy of differentiation between the 2 groups. Methods: CERAD-nb scores were obtained from AD patients (n = 389, 58% women, mean age 74.0 years) and from controls (n = 1,980, 52% women, mean age 68.5 years). The differences in CERAD-nb performance were evaluated by univariate GLM. Differentiation between the 2 groups was evaluated using a receiver operating characteristic (ROC) curve, where a larger area under the ROC curve represents better discrimination. Youden’s J was calculated for the overall performance and accuracy of each of the measures. Results: Of the demographic factors, education was the strongest predictor of CERAD-nb performance, explaining more variation than age or gender in both the AD patients and the controls. Education corrected cutoff scores had better diagnostic accuracy in discriminating between the AD patients and controls than existing uncorrected scores. The highest level of discrimination between the 2 groups overall was found for two CERAD-nb total scores. Conclusions: Education-corrected cutoff scores were superior to uncorrected scores in differentiating between controls and AD patients especially for the highest level of education and should therefore be used in clinical cognitive screening, also as the proportion of the educated elderly is increasing substantially during the 2020s. Our results also indicate that total scores of the CERAD-nb are better at discriminating AD patients from controls than any single subtest score. A digital tool for calculating the total scores and comparing education-based cutoffs would increase the efficiency and usability of the test.Peer reviewe
Study protocol for development and validation of a single tool to assess risks of stroke, diabetes mellitus, myocardial infarction and dementia: DemNCD-Risk
Introduction Current efforts to reduce dementia focus on prevention and risk reduction by targeting modifiable risk factors. As dementia and cardiometabolic non-communicable diseases (NCDs) share risk factors, a single risk-estimating tool for dementia and multiple NCDs could be cost-effective and facilitate concurrent assessments as compared with a conventional single approach. The aim of this study is to develop and validate a new risk tool that estimates an individual's risk of developing dementia and other NCDs including diabetes mellitus, stroke and myocardial infarction. Once validated, it could be used by the public and general practitioners. Methods and analysis Ten high-quality cohort studies from multiple countries were identified, which met eligibility criteria, including large representative samples, long-term follow-up, data on clinical diagnoses of dementia and NCDs, recognised modifiable risk factors for the four NCDs and mortality data. Pooled harmonised data from the cohorts will be used, with 65% randomly allocated for development of the predictive model and 35% for testing. Predictors include sociodemographic characteristics, general health risk factors and lifestyle/behavioural risk factors. A subdistribution hazard model will assess the risk factors' contribution to the outcome, adjusting for competing mortality risks. Point-based scoring algorithms will be built using predictor weights, internally validated and the discriminative ability and calibration of the model will be assessed for the outcomes. Sensitivity analyses will include recalculating risk scores using logistic regression. Ethics and dissemination Ethics approval is provided by the University of New South Wales Human Research Ethics Committee (UNSW HREC; protocol numbers HC200515, HC3413). All data are deidentified and securely stored on servers at Neuroscience Research Australia. Study findings will be presented at conferences and published in peer-reviewed journals. The tool will be accessible as a public health resource. Knowledge translation and implementation work will explore strategies to apply the tool in clinical practice
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