5251
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Younes L, Albert M, Moghekar A, Soldan A, Pettigrew C, Miller MI. Identifying Changepoints in Biomarkers During the Preclinical Phase of Alzheimer's Disease. Front Aging Neurosci 2019; 11:74. [PMID: 31001108 PMCID: PMC6454004 DOI: 10.3389/fnagi.2019.00074] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 03/14/2019] [Indexed: 01/29/2023] Open
Abstract
Objective: Several models have been proposed for the evolution of Alzheimer's disease (AD) biomarkers. The aim of this study was to identify changepoints in a range of biomarkers during the preclinical phase of AD. Methods: We examined nine measures based on cerebrospinal fluid (CSF), magnetic resonance imaging (MRI) and cognitive testing, obtained from 306 cognitively normal individuals, a subset of whom subsequently progressed to the symptomatic phase of AD. A changepoint model was used to determine which of the measures had a significant change in slope in relation to clinical symptom onset. Results: All nine measures had significant changepoints, all of which preceded symptom onset, however, the timing of these changepoints varied considerably. A single measure, CSF t-tau, had an early changepoint (34 years prior to symptom onset). A group of measures, including the remaining CSF measures (CSF Abeta and phosphorylated tau) and all cognitive tests had changepoints 10-15 years prior to symptom onset. A second group is formed by medial temporal lobe shape composite measures, with a 6-year time difference between the right and left side (respectively nine and 3 years prior to symptom onset). Conclusion: These findings highlight the long period of time prior to symptom onset during which AD pathology is accumulating in the brain. There are several significant findings, including the early changes in cognition and the laterality of the MRI findings. Additional work is needed to clarify their significance.
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Affiliation(s)
- Laurent Younes
- Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD, United States
| | - Marilyn Albert
- Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
| | - Abhay Moghekar
- Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
| | - Anja Soldan
- Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
| | - Corinne Pettigrew
- Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
| | - Michael I Miller
- Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD, United States.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States
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5252
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Kraus A, Saijo E, Metrick MA, Newell K, Sigurdson CJ, Zanusso G, Ghetti B, Caughey B. Seeding selectivity and ultrasensitive detection of tau aggregate conformers of Alzheimer disease. Acta Neuropathol 2019; 137:585-598. [PMID: 30570675 PMCID: PMC6426988 DOI: 10.1007/s00401-018-1947-3] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 12/05/2018] [Accepted: 12/06/2018] [Indexed: 10/28/2022]
Abstract
Alzheimer disease (AD) and chronic traumatic encephalopathy (CTE) involve the abnormal accumulation in the brain of filaments composed of both three-repeat (3R) and four-repeat (4R) (3R/4R) tau isoforms. To probe the molecular basis for AD's tau filament propagation and to improve detection of tau aggregates as potential biomarkers, we have exploited the seeded polymerization growth mechanism of tau filaments to develop a highly selective and ultrasensitive cell-free tau seed amplification assay optimized for AD (AD real-time quaking-induced conversion or AD RT-QuIC). The reaction is based on the ability of AD tau aggregates to seed the formation of amyloid fibrils made of certain recombinant tau fragments. AD RT-QuIC detected seeding activity in AD (n = 16) brains at dilutions as extreme as 107-1010-fold, but was 102-106-fold less responsive when seeded with brain from most cases of other types of tauopathy with comparable loads of predominant 3R or 4R tau aggregates. For example, AD brains had average seeding activities that were orders of magnitude higher than Pick disease brains with predominant 3R tau deposits, but the opposite was true using our previously described Pick-optimized tau RT-QuIC assay. CTE brains (n = 2) had seed concentrations comparable to the weakest of the AD specimens, and higher than 3 of 4 specimens with 3R/4R primary age-related tauopathy. AD seeds shared properties with the tau filaments found in AD brains, as AD seeds were sarkosyl-insoluble, protease resistant, and reactive with tau antibodies. Moreover, AD RT-QuIC detected as little as 16 fg of pure synthetic tau fibrils. The distinctive seeding activity exhibited by AD and CTE tau filaments compared to other types of tauopathies in these seeded polymerization reactions provides a mechanistic basis for their consistent propagation as specific conformers in patients with 3R/4R tau diseases. Importantly, AD RT-QuIC also provides rapid ultrasensitive quantitation of 3R/4R tau-seeding activity as a biomarker.
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5253
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Arenaza-Urquijo EM, Przybelski SA, Lesnick TL, Graff-Radford J, Machulda MM, Knopman DS, Schwarz CG, Lowe VJ, Mielke MM, Petersen RC, Jack CR, Vemuri P. The metabolic brain signature of cognitive resilience in the 80+: beyond Alzheimer pathologies. Brain 2019; 142:1134-1147. [PMID: 30851100 PMCID: PMC6439329 DOI: 10.1093/brain/awz037] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 12/04/2018] [Accepted: 12/21/2018] [Indexed: 11/14/2022] Open
Abstract
Research into cognitive resilience imaging markers may help determine the clinical significance of Alzheimer's disease pathology among older adults over 80 years (80+). In this study, we aimed to identify a fluorodeoxyglucose (FDG)-PET based imaging marker of cognitive resilience. We identified 457 participants ≥ 80 years old (357 cognitively unimpaired, 118 cognitively impaired at baseline, mean age of 83.5 ± 3.2 years) from the population-based Mayo Clinic Study of Aging (MCSA) with baseline MRI, Pittsburgh compound B-PET and FDG-PET scans and neuropsychological evaluation. We identified a subset of 'resilient' participants (cognitively stable 80+, n = 192) who maintained normal cognition for an average of 5 years (2-10 years). Global PIB ratio, FDG-PET ratio and cortical thickness from Alzheimer's disease signature regions were used as Alzheimer's disease imaging biomarker outcomes and global cognitive z-score was used as a cognitive outcome. First, using voxel-wise multiple regression analysis, we identified the metabolic areas underlying cognitive resilience in cognitively stable 80+ participants, which we call the 'resilience signature'. Second, using multivariate linear regression models, we evaluated the association of risk and protective factors with the resilience signature and its added value for predicting global cognition beyond established Alzheimer's disease imaging biomarkers in the full 80+ sample. Third, we evaluated the utility of the resilience signature in conjunction with amyloidosis in predicting longitudinal cognition using linear mixed effect models. Lastly, we assessed the utility of the resilience signature in an independent cohort using ADNI (n = 358, baseline mean age of 80 ± 3.8). Our main findings were: (i) FDG-PET uptake in the bilateral anterior cingulate cortex and anterior temporal pole was associated with baseline global cognition in cognitively stable 80+ (the resilience signature); (ii) established Alzheimer's disease imaging biomarkers did not predict baseline global cognition in this subset of participants; (iii) in the full MCSA 80+ and ADNI cohorts, amyloid burden and FDG-PET in the resilience signature were the stronger predictors of baseline global cognition; (iv) sex and systemic vascular health predicted FDG-PET in the resilience signature, suggesting vascular health maintenance as a potential pathway to preserve the metabolism of these areas; and (v) the resilience signature provided significant information about global longitudinal cognitive change even when considering amyloid status in both the MCSA and ADNI cohorts. The FDG-PET resilience signature may be able to provide important information in conjunction with other Alzheimer's disease biomarkers for the determination of clinical prognosis. It may also facilitate identification of disease targeting modifiable risk factors such as vascular health maintenance.
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Affiliation(s)
| | | | | | | | - Mary M Machulda
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, Minnesota, USA
| | - David S Knopman
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Val J Lowe
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Michelle M Mielke
- Health Science Research, Mayo Clinic, Rochester, Minnesota, USA
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Clifford R Jack
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
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5254
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Hill E, Goodwill AM, Gorelik A, Szoeke C. Diet and biomarkers of Alzheimer's disease: a systematic review and meta-analysis. Neurobiol Aging 2019; 76:45-52. [DOI: 10.1016/j.neurobiolaging.2018.12.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 11/29/2018] [Accepted: 12/18/2018] [Indexed: 11/16/2022]
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5255
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Li H, Fan Y. EARLY PREDICTION OF ALZHEIMER'S DISEASE DEMENTIA BASED ON BASELINE HIPPOCAMPAL MRI AND 1-YEAR FOLLOW-UP COGNITIVE MEASURES USING DEEP RECURRENT NEURAL NETWORKS. PROCEEDINGS. IEEE INTERNATIONAL SYMPOSIUM ON BIOMEDICAL IMAGING 2019; 2019:368-371. [PMID: 31803346 PMCID: PMC6892161 DOI: 10.1109/isbi.2019.8759397 10.1109/isbi.2019.8759397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Multi-modal biological, imaging, and neuropsychological markers have demonstrated promising performance for distinguishing Alzheimer's disease (AD) patients from cognitively normal elders. However, it remains difficult to early predict when and which mild cognitive impairment (MCI) individuals will convert to AD dementia. Informed by pattern classification studies which have demonstrated that pattern classifiers built on longitudinal data could achieve better classification performance than those built on cross-sectional data, we develop a deep learning model based on recurrent neural networks (RNNs) to learn informative representation and temporal dynamics of longitudinal cognitive measures of individual subjects and combine them with baseline hippocampal MRI for building a prognostic model of AD dementia progression. Experimental results on a large cohort of MCI subjects have demonstrated that the deep learning model could learn informative measures from longitudinal data for characterizing the progression of MCI subjects to AD dementia, and the prognostic model could early predict AD progression with high accuracy.
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Affiliation(s)
- Hongming Li
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yong Fan
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
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5256
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Grill JD, Nuño MM, Gillen DL. Which MCI Patients Should be Included in Prodromal Alzheimer Disease Clinical Trials? Alzheimer Dis Assoc Disord 2019; 33:104-112. [PMID: 30958413 PMCID: PMC6538436 DOI: 10.1097/wad.0000000000000303] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Prodromal Alzheimer disease (AD) clinical trials enroll patients with mild cognitive impairment (MCI) meeting biomarker criteria, but specific enrollment criteria vary among trials. METHODS We used data from AD Neuroimaging Initiative (ADNI) MCI participants to assess AD biomarker eligibility, variation in trial outcome measures, and statistical power. RESULTS Most (65%) participants meet eligibility criteria based on low cerebrospinal fluid amyloid beta (Aβ). Relative to trials enrolling exclusively based on low cerebrospinal fluid Aβ, trials including participants with a high ratio of phosphorylated tau to Aβ would include an additional 15% of participants. Fewer (34% to 62%) participants met criteria for Aβ and tau. Differences in clinical and demographic characteristics of modeled trial samples were minimal. Those with low Aβ and high tau showed the greatest change over time on outcome measures. CONCLUSIONS Eligibility rates for prodromal trials vary depending on the specific biomarker criteria, though differences in demographics and the variation associated with outcome measures are minimal. Broadening inclusion criteria beyond amyloid alone may facilitate recruitment but include patients showing slower progression over time. Biomarker criteria selection should be informed by the goal of enrolling individuals most likely to utilize and benefit from the intervention under investigation in a particular setting.
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Affiliation(s)
- Joshua D. Grill
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine,
CA
- Department of Psychiatry and Human Behavior, University of California, Irvine, Irvine, CA, USA
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Michelle M. Nuño
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine,
CA
- Department of Statistics, University of California, Irvine, Irvine, CA, USA
| | - Daniel L. Gillen
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine,
CA
- Department of Statistics, University of California, Irvine, Irvine, CA, USA
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5257
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Timmers M, Tesseur I, Bogert J, Zetterberg H, Blennow K, Börjesson-Hanson A, Baquero M, Boada M, Randolph C, Tritsmans L, Van Nueten L, Engelborghs S, Streffer JR. Relevance of the interplay between amyloid and tau for cognitive impairment in early Alzheimer's disease. Neurobiol Aging 2019; 79:131-141. [PMID: 31055223 DOI: 10.1016/j.neurobiolaging.2019.03.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/08/2019] [Accepted: 03/25/2019] [Indexed: 01/23/2023]
Abstract
Amyloid β (Aβ) and tau are key hallmark features of Alzheimer's disease (AD) neuropathology. The interplay of Aβ and tau for cognitive impairment in early AD was examined with cross-sectional analysis, measured by cerebrospinal fluid biomarkers (Aβ1-42, total tau [t-tau], and phosphorylated tau [p-tau181P]), and on cognitive performance by the repeatable battery for assessment of neuropsychological status (RBANS). Participants (n = 246) included cognitively normal (Aβ-), mild cognitively impaired (Aβ-), preclinical AD (Aβ+), and prodromal AD (Aβ+). Overall, cognitive scores (RBANS total scale score) had a moderate negative correlation to t-tau (n = 246; r = -0.434; p < 0.001) and p-tau181P (r = -0.389; p < 0.001). When classified by Aβ status, this correlation to t-tau was applicable only in Aβ+ participants (n = 139; r = -0.451, p < 0.001) but not Aβ- participants (n = 107; r = 0.137, p = 0.16), with identical findings for p-tau. Both tau (p < 0.0001) and interaction of Aβ1-42 with tau (p = 0.006) affected RBANS, but not Aβ1-42 alone. Cognitive/memory performance correlated well with cerebrospinal fluid tau levels across early stages of AD, although the correlation is Aβ dependent.
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Affiliation(s)
- Maarten Timmers
- Janssen Research and Development, A Division of Janssen Pharmaceutica N.V., Beerse, Belgium; Reference Center for Biological Markers of Dementia (BIODEM), Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
| | - Ina Tesseur
- Janssen Research and Development, A Division of Janssen Pharmaceutica N.V., Beerse, Belgium
| | | | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistery Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK; UK Dementia Research Institute at UCL, London, UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistery Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Anne Börjesson-Hanson
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden; Sahlgrenska University Hospital, Mölndal, Sweden; Clinical Trials, Theme Aging, Karolinska University Hospital, Stockholm, Sweden
| | - Miquel Baquero
- Neurology Department, Hospital Universitari I Politecnic La Fe, Valencia, Spain
| | - Mercè Boada
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya-Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
| | - Christopher Randolph
- MedAvante-ProPhase, Hamilton, NJ, USA; Department of Neurology, Loyola University Medical Center, Maywood, IL, USA
| | - Luc Tritsmans
- Janssen Research and Development, A Division of Janssen Pharmaceutica N.V., Beerse, Belgium
| | - Luc Van Nueten
- Janssen Research and Development, A Division of Janssen Pharmaceutica N.V., Beerse, Belgium
| | - Sebastiaan Engelborghs
- Reference Center for Biological Markers of Dementia (BIODEM), Institute Born-Bunge, University of Antwerp, Antwerp, Belgium; Department of Neurology and Center for Neurosciences, UZ Brussel and Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Johannes Rolf Streffer
- Janssen Research and Development, A Division of Janssen Pharmaceutica N.V., Beerse, Belgium; Reference Center for Biological Markers of Dementia (BIODEM), Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
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5258
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Brookmeyer R, Abdalla N. Design and sample size considerations for Alzheimer's disease prevention trials using multistate models. Clin Trials 2019; 16:111-119. [PMID: 30922116 PMCID: PMC6442939 DOI: 10.1177/1740774518816323] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND/AIMS Clinical trials for Alzheimer's disease have been aimed primarily at persons who have cognitive symptoms at enrollment. However, researchers are now recognizing that the pathophysiological process of Alzheimer's disease begins years, if not decades, prior to the onset of clinical symptoms. Successful intervention may require intervening early in the disease process. Critical issues arise in designing clinical trials for primary and secondary prevention of Alzheimer's disease including determination of sample sizes and follow-up duration. We address a number of these issues through application of a unifying multistate model for the preclinical course of Alzheimer's disease. A multistate model allows us to specify at which points during the long disease process the intervention exerts its effects. METHODS We used a nonhomogeneous Markov multistate model for the progression of Alzheimer's disease through preclinical disease states defined by biomarkers, mild cognitive impairment and Alzheimer's disease dementia. We used transition probabilities based on several published cohort studies. Sample size methods were developed that account for factors including the initial preclinical disease state of trial participants, the primary endpoint, age-dependent transition and mortality rates and specifications of which transition rates are the targets of the intervention. RESULTS We find that Alzheimer's disease prevention trials with a clinical primary endpoint of mild cognitive impairment or Alzheimer's disease dementia will require sample sizes of the order many thousands of individuals with at least 5 years of follow-up, which is larger than most Alzheimer's disease therapeutic trials conducted to date. The reasons for the large trial sizes include the long and variable preclinical period that spans decades, high rates of attrition among elderly populations due to mortality and losses to follow-up and potential selection effects, whereby healthier subjects enroll in prevention trials. A web application is available to perform sample size calculations using the methods reported here. CONCLUSION Sample sizes based on multistate models can account for the points in the disease process when interventions exert their effects and may lead to more accurate sample size determinations. We will need innovative strategies to help design Alzheimer's disease prevention trials with feasible sample size requirements and durations of follow-up.
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Affiliation(s)
- Ron Brookmeyer
- Department of Biostatistics, University of California, Los Angeles, Los Angeles, CA, USA
| | - Nada Abdalla
- Department of Biostatistics, University of California, Los Angeles, Los Angeles, CA, USA
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5259
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Editorial: Facing up to the complexity of neuro degenerative disorders in order to deal with them more effectively. Curr Opin Neurol 2019; 32:253-254. [DOI: 10.1097/wco.0000000000000670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5260
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Optimization of solid-phase extraction (SPE) in the preparation of [18F]D3FSP: A new PET imaging agent for mapping Aβ plaques. Nucl Med Biol 2019; 71:54-64. [DOI: 10.1016/j.nucmedbio.2019.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/09/2019] [Accepted: 05/09/2019] [Indexed: 11/21/2022]
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5261
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Liew TM, Yap P, Ng TP, Mahendran R, Kua EH, Feng L. Symptom clusters of subjective cognitive decline amongst cognitively normal older persons and their utilities in predicting objective cognitive performance: structural equation modelling. Eur J Neurol 2019; 26:1153-1160. [PMID: 30924985 DOI: 10.1111/ene.13958] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 03/18/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND PURPOSE Prior literature on subjective cognitive decline (SCD) has mostly focused on memory complaints. It is uncertain whether the other non-memory complaints are equally relevant and can be used, alongside memory complaints, to identify populations at high risk of cognitive impairment. How the memory and non-memory complaints of SCD cluster with each other amongst community-dwelling individuals was investigated, and the differential utility of the symptom clusters of SCD in predicting objective cognitive performance was evaluated. METHODS This study included 736 participants who were ≥60 years and had normal cognition, using the baseline data of an ongoing cohort study. Participants completed baseline assessments which comprised an SCD scale, a global cognitive measure and neuropsychological tests. Symptom clusters of SCD - as identified from exploratory and confirmatory factor analyses - were included in structural equation models to predict baseline changes in neuropsychological tests. RESULTS The symptoms of SCD were split into two distinct factors, of which factor 1 was reported much more frequently than factor 2. Each standard deviation (SD) increment in factor 1 led to a 0.16-0.50 SD increase in global cognition, immediate memory, visuospatial abilities, language, attention and delayed memory (P < 0.05). In contrast, each SD increment in factor 2 worsened some of the cognitive domains by 0.18-0.37 SD. CONCLUSIONS The various complaints of SCD can have different implications amongst cognitively normal older persons and may possibly be classified into age-related symptoms and pathological symptoms. The findings highlight the need for caution when selecting SCD measures, and illustrate the potential utility of SCD subtypes to inform on the underlying neurobiology.
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Affiliation(s)
- T M Liew
- Department of Geriatric Psychiatry, Institute of Mental Health, Singapore, Singapore.,Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - P Yap
- Department of Geriatric Medicine, Khoo Teck Puat Hospital, Singapore, Singapore.,Geriatric Education and Research Institute, Singapore, Singapore
| | - T-P Ng
- Department of Psychological Medicine, National University Hospital, Singapore, Singapore.,Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - R Mahendran
- Department of Psychological Medicine, National University Hospital, Singapore, Singapore.,Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - E-H Kua
- Department of Psychological Medicine, National University Hospital, Singapore, Singapore.,Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - L Feng
- Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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5262
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Bransby L, Lim YY, Ames D, Fowler C, Roberston J, Harrington K, Snyder PJ, Villemagne VL, Salvado O, Masters CL, Maruff P. Sensitivity of a Preclinical Alzheimer's Cognitive Composite (PACC) to amyloid β load in preclinical Alzheimer's disease. J Clin Exp Neuropsychol 2019; 41:591-600. [PMID: 30924399 DOI: 10.1080/13803395.2019.1593949] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Introduction: Preclinical Alzheimer's disease (AD) is characterized by amyloid-related cognitive decline. Reduction in this decline is used to determine the efficacy of drug therapies designed to forestall the disease in preclinical AD clinical trials, measured by a Preclinical Alzheimer's Cognitive Composite (PACC). Most studies estimate rates of cognitive change by comparing cognitively normal (CN) older adults with abnormally high beta-amyloid (Aβ+) to those with low levels (Aβ-). However, participants of preclinical AD clinical trials must be Aβ+ for entry. Therefore, we estimated the effect of very high amyloid (Aβ++) and Aβ+ on cognitive change over three years measured by different versions of the PACC in individuals with preclinical AD. Method: CN older adults underwent Aβ neuroimaging and neuropsychological assessments over three years as part of the Australian Imaging, Biomarkers and Lifestyle (AIBL) study. Three cognitive composite scores were computed: the Alzheimer's Disease Cooperative Study (ADCS)-PACC, the ADCS-PACC with no Mini-Mental State Examination (MMSE), and the z-scores of Attention, Verbal Fluency and Episodic Memory for Nondemented Older Adults (ZAVEN) composite. Results: Compared to the Aβ++ group, the Aβ+ group showed a slower rate of cognitive decline with the largest magnitude of difference reflected by the ADCS-PACC (d = 0.85). The ADCS-PACC excluding the MMSE and the ZAVEN also reflected a moderate to large magnitude of difference between groups (d = 0.62, d = 0.72, respectively). Conclusions: When all individuals have abnormal Aβ, the level of Aβ at baseline is associated with the rate of subsequent decline. The ADCS-PACC was the most sensitive composite score in showing that lower Aβ is associated with a slower rate of cognitive decline; however, there are limitations to the use of the MMSE. These results provide a benchmark of comparison for preclinical AD clinical trials aiming to slow cognitive deterioration.
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Affiliation(s)
- Lisa Bransby
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia
| | - Yen Ying Lim
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia
| | - David Ames
- b National Ageing Research Institute , Melbourne , VIC , Australia.,c Academic Unit for Psychiatry of Old Age, St. Vincent's Health , The University of Melbourne , Melbourne , VIC , Australia
| | - Christopher Fowler
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia
| | - Joanne Roberston
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia
| | - Karra Harrington
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia.,d Cooperative Research Centre for Mental Health , Parkville , Australia
| | - Peter J Snyder
- e Ryan Institute for Neuroscience , University of Rhode Island , Kingston , RI , USA
| | - Victor L Villemagne
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia.,f Department of Nuclear Medicine and Centre for PET , Austin Health , Melbourne , VIC , Australia.,g Department of Medicine, Austin Health , The University of Melbourne , Melbourne , VIC , Australia
| | - Olivier Salvado
- h Commonwealth Scientific Industrial Research Organization (CSIRO) Preventative Health National Research Flagship , Australian e-Health Research Centre-BiaMedIA , Brisbane , QLD , Australia
| | - Colin L Masters
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia
| | - Paul Maruff
- a The Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Melbourne , VIC , Australia.,i CogState Ltd ., Melbourne , VIC , Australia
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5263
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Takeuchi J, Kikukawa T, Saito H, Hasegawa I, Takeda A, Hatsuta H, Kawabe J, Wada Y, Mawatari A, Igesaka A, Doi H, Watanabe Y, Shimada H, Kitamura S, Higuchi M, Suhara T, Itoh Y. Amyloid-Negative Dementia in the Elderly is Associated with High Accumulation of Tau in the Temporal Lobes. Open Biomed Eng J 2019. [DOI: 10.2174/1874120701913010055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Background:
We previously reported that among cases clinically diagnosed with Alzheimer’s disease, the proportion of amyloid beta (Aβ) -negative case increases in the elderly population. Tauopathy including Argyrophilic Grain Disease (AGD) and Neurofibrillary Tangle-Predominant Dementia (NFTPD), may be the leading causes of such dementia.
Objective:
To evaluate the involvement of tau, we studied tau accumulation in Amyloid-Negative Dementia Cases in the Elderly (ANDE) with Positron Emission Tomography (PET).
Methods:
Seven cases with slowly progressive dementia who were older than 80 years and were negative for Aβ were studied. In one case, autopsy obtained 2 years after the PET examination revealed neurofibrillary tangles limited around the parahippocampal gyrus. Four cases showed strong laterality in magnetic resonance imaging atrophy (clinical AGD), while the other three cases had no significant laterality in atrophy (clinical NFTPD). Age-corrected PET data of healthy controls (HC; n = 12) were used as control. Tau accumulation was evaluated with [11C]PBB3-PET.
Results:
High accumulation was found in the lateral temporal cortex in ANDE. In autopsy case, scattered neurofibrillary tangles were found in the parahippocampal gyrus. In addition, there was a very high accumulation of PBB3 in the large area of bilateral parietal lobes, although no corresponding tau component was found in the autopsied case.
Conclusion:
Relatively high burden of tau deposition was commonly observed in the lateral temporal cortex and parietal cortex of ANDE, part of which may explain dementia in these subjects. [11C]PBB3 may be useful in detecting tauopathy in ANDE.
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5264
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CSF level of β-amyloid peptide predicts mortality in Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2019; 11:29. [PMID: 30922415 PMCID: PMC6440001 DOI: 10.1186/s13195-019-0481-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/08/2019] [Indexed: 12/31/2022]
Abstract
Objective Alzheimer’s disease (AD) is the sixth leading cause of death, with an average survival estimated between 5 and 10 years after diagnosis. Despite recent advances in diagnostic criteria of AD, few studies have used biomarker-based diagnostics to determine the prognostic factors of AD. We investigate predictors of death and institutionalization in a population of AD patients with high probability of AD physiopathology process assessed by positivity of three CSF biomarkers. Methods Three hundred twenty-one AD patients with abnormal values for CSF beta-amyloid peptide (Aβ42), tau, and phosphorylated tau levels were recruited from a memory clinic-based registry between 2008 and 2017 (Lariboisiere hospital, Paris, France) and followed during a median period of 3.9 years. We used multivariable Cox models to estimate the hazard ratio (HR) of death and institutionalization for baseline clinical data, genotype of the apolipoprotein E (APOE), and levels of CSF biomarkers. Results A total of 71 (22%) patients were institutionalized and 57 (18%) died during the follow-up. Greater age, male sex, lower MMSE score, and lower CSF Aβ42 level were associated with an increased risk of mortality. One standard deviation lower CSF Aβ42 (135 pg/mL) was associated with a 89% increased risk of death (95% CI = 1.25–2.86; p = 0.002). This association was not modified by age, sex, education, APOE ε4, and disease severity. There was no evidence of an association of tau CSF biomarkers with mortality. None of the CSF biomarkers were associated with institutionalization. Conclusions Lower CSF Aβ42 is a strong prognostic marker of mortality in AD patients, independently of age or severity of the disease. Whether drugs targeting beta-amyloid peptide could have an effect on mortality of AD patients should be investigated in future clinical trials.
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5265
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Putcha D, Brickhouse M, Wolk DA, Dickerson BC. Fractionating the Rey Auditory Verbal Learning Test: Distinct roles of large-scale cortical networks in prodromal Alzheimer's disease. Neuropsychologia 2019; 129:83-92. [PMID: 30930301 DOI: 10.1016/j.neuropsychologia.2019.03.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 02/22/2019] [Accepted: 03/25/2019] [Indexed: 11/17/2022]
Abstract
Successful episodic memory calls upon a number of different cognitive processes that are supported by the coordination of several large-scale cortical networks. Previous work from our group has demonstrated dissociable anatomic substrates at different stages of memory in patients with dementia due to Alzheimer's disease (AD). The aim of the current study was to extend the understanding of brain-behavior associations underlying a commonly administered neuropsychological assessment of verbal episodic memory (Rey Auditory Verbal Learning Test; RAVLT) by determining the cortical network contributions to the performance at early vs. late stages of list learning, delayed recall, and retention, in 235 very mild biomarker positive (A+/T+/N+) individuals diagnosed with amnestic mild cognitive impairment (aMCI; MMSE = 27.7). We measured cortical atrophy in four large-scale cortical networks impacted by AD: default mode (DMN), dorsal attention (DAN), frontoparietal (FPN), and language (LN) networks. We also evaluated the role of hippocampal atrophy at each stage of memory performance. Partial correlation analyses controlling for age, sex, and education and corrected for multiple comparisons revealed that early learning was most strongly associated with cortical thickness in the DAN, while late learning was most strongly associated with hippocampal volume, but also related to cortical thickness in the DAN, FPN, DMN, and LN. Delayed recall was associated most strongly with hippocampal volume, but was also related to cortical thickness in the FPN and DMN, while retention was associated only with hippocampal volume. These findings are consistent with prior models of the neural substrates of different stages of verbal list learning and retrieval, provide new insights into the cortical networks undergoing neurodegeneration even at very mild stages of prodromal AD, and inform our thinking about the networks and regions being interrogated by this kind of neuropsychological assessment of episodic memory.
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Affiliation(s)
| | - Michael Brickhouse
- Department of Neurology, Frontotemporal Disorders Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - David A Wolk
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Bradford C Dickerson
- Department of Neurology, Frontotemporal Disorders Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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5266
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Paranjpe MD, Chen X, Liu M, Paranjpe I, Leal JP, Wang R, Pomper MG, Wong DF, Benzinger TLS, Zhou Y. The effect of ApoE ε4 on longitudinal brain region-specific glucose metabolism in patients with mild cognitive impairment: a FDG-PET study. Neuroimage Clin 2019; 22:101795. [PMID: 30991617 PMCID: PMC6449776 DOI: 10.1016/j.nicl.2019.101795] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 03/12/2019] [Accepted: 03/24/2019] [Indexed: 11/02/2022]
Abstract
While the ApoE ε4 allele is a known risk factor for mild cognitive impairment (MCI) and Alzheimer's disease, brain region specific effects remain elusive. In this study, we investigate whether the ApoE ε4 allele exhibits brain region specific effects in longitudinal glucose uptake among patients with MCI from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Preprocessed FDG PET images, MRIs, and demographic information were downloaded from the ADNI database. An iterative reblurred Van Cittertiteration method was used for partial volume correction (PVC) on all PET images. Structural MRIs were used for PET spatial normalization and region of interest (ROI) definition in standard space. Longitudinal changes in ROI FDG standardized uptake value ratio (SUVR) relative to cerebellum in 24 ApoE ε4 carriers and 24 age-matched ApoE ε4 non-carriers were measured for up to 84-months (median 72 months, SD = 11.2 months) and compared using a generalized linear mixed effects model controlling for gender, education, baseline age, and follow-up period. Additionally, voxelwise analysis was performed by implementing a paired t-test comparing matched baseline and 72 month FDG SUVR images in ApoE carriers and non-carriers separately. Results with PVC were compared with ones from non-PVC based analysis. After applying PVC, the superior fontal, parietal, lateral temporal, medial temporal, caudate, thalamus, and post-cingulate, and amygdala regions had greater longitudinal decreases in FDG uptake in ApoE ε4 carriers with MCI compared to non-carriers with MCI. Similar forebrain and limbic clusters were found through voxelwise analysis. Compared to the PVC based analysis, fewer significant ApoE-associated regions and clusters were found in the non-PVC based PET analysis. Our findings suggest that the ApoE ε4 genotype is associated with a longitudinal decline in glucose uptake in 8 forebrain and limbic brain regions in the context of MCI. In conclusion, this 84-months longitudinal FDG PET study demonstrates a novel ApoE ε4-associated brain-region specific glucose metabolism pattern in patients with MCI. Partial volume correction improved FDG PET quantification.
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Affiliation(s)
- Manish D Paranjpe
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Xueqi Chen
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, China
| | - Min Liu
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States; Department of Nuclear Medicine, Peking University First Hospital, Beijing, China
| | - Ishan Paranjpe
- Icahn School of Medicine at Mount Sinai, NY, New York, United States
| | - Jeffrey P Leal
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Rongfu Wang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, China
| | - Martin G Pomper
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Dean F Wong
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
| | - Tammie L S Benzinger
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, United States
| | - Yun Zhou
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States; Department of Nuclear Medicine, Peking University First Hospital, Beijing, China; Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, United States.
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5267
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Anderson AJ, Lin F. How pattern information analyses of semantic brain activity elicited in language comprehension could contribute to the early identification of Alzheimer's Disease. Neuroimage Clin 2019; 22:101788. [PMID: 30991624 PMCID: PMC6451171 DOI: 10.1016/j.nicl.2019.101788] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 01/28/2019] [Accepted: 03/22/2019] [Indexed: 12/19/2022]
Abstract
Alzheimer's disease (AD) is associated with a loss of semantic knowledge reflecting brain pathophysiology that begins years before dementia. Identifying early signs of pathophysiology induced dysfunction in the neural systems that access and process words' meaning could therefore help forecast dementia. This article reviews pioneering studies demonstrating that abnormal functional Magnetic Resonance Imaging (fMRI) response patterns elicited in semantic tasks reflect both AD-pathophysiology and the hereditary risk of AD, and also can help forecast cognitive decline. However, to bring current semantic task-based fMRI research up to date with new AD research guidelines the relationship with different types of AD-pathophysiology needs to be more thoroughly examined. We shall argue that new analytic techniques and experimental paradigms will be critical for this. Previous work has relied on specialized tests of specific components of semantic knowledge/processing (e.g. famous name recognition) to reveal coarse AD-related changes in activation across broad brain regions. Recent computational advances now enable more detailed tests of the semantic information that is represented within brain regions during more natural language comprehension. These new methods stand to more directly index how pathophysiology alters neural information processing, whilst using language comprehension as the basis for a more comprehensive examination of semantic brain function. We here connect the semantic pattern information analysis literature up with AD research to raise awareness to potential cross-disciplinary research opportunities.
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Affiliation(s)
- Andrew James Anderson
- Department of Neuroscience, University of Rochester Medical Center, United States of America.
| | - Feng Lin
- Department of Neuroscience, University of Rochester Medical Center, United States of America; School of Nursing, University of Rochester Medical Center, United States of America; Department of Psychiatry, University of Rochester Medical Center, United States of America; Department of Neurology, University of Rochester Medical Center, United States of America; Department of Brain and Cognitive Sciences, University of Rochester, United States of America.
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5268
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Alexopoulos P, Thierjung N, Economou P, Werle L, Buhl F, Kagerbauer S, Papanastasiou AD, Grimmer T, Gourzis P, Berthele A, Hemmer B, Kübler H, Martin J, Politis A, Perneczky R. Plasma Levels of Soluble AβPPβ as a Biomarker for Alzheimer's Disease with Dementia. J Alzheimers Dis 2019; 69:83-90. [PMID: 30909232 DOI: 10.3233/jad-181088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cost- and time-effective markers of Alzheimer's disease (AD), reliable and feasible at the population level are urgently needed. Soluble amyloid-β protein precursor β (sAβPPβ) in plasma has attracted scientific attention as a potential AD biomarker candidate. Here we report that plasma sAβPPβ levels in patients with AD dementia and typical for AD cerebrospinal fluid (CSF) biomarker profiles (N = 33) are significantly lower (p < 0.01) than those of cognitively healthy elderly individuals without AD (N = 39), while CSF sAβPPβ levels did not differ between the studied groups. This provides further evidence for the potential of sAβPPβ in plasma as an AD biomarker candidate.
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Affiliation(s)
- Panagiotis Alexopoulos
- Department of Psychiatry and Psychotherapy, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Department of Psychiatry, University Hospital of Rion, University of Patras, Patras, Greece
| | - Nathalie Thierjung
- Department of Psychiatry and Psychotherapy, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Polychronis Economou
- Department of Civil Engineering (Statistics), University of Patras, Patras, Greece
| | - Lukas Werle
- Department of Psychiatry and Psychotherapy, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Max Planck Institute of Psychiatry, Munich, Germany
| | - Felix Buhl
- Department of Psychiatry and Psychotherapy, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Simone Kagerbauer
- Department of Anaesthesiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Anastasios D Papanastasiou
- Molecular Oncology Laboratory, Division of Oncology, University Hospital of Patras, University of Patras, Patras, Greece
| | - Timo Grimmer
- Department of Psychiatry and Psychotherapy, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Philippos Gourzis
- Department of Psychiatry, University Hospital of Rion, University of Patras, Patras, Greece
| | - Achim Berthele
- Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Bernhard Hemmer
- Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Hubert Kübler
- Department of Urology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Jan Martin
- Department of Anaesthesiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Antonios Politis
- First Department of Psychiatry, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece.,Department of Psychiatry, Division of Geriatric Psychiatry and Neuropsychiatry, Johns Hopkins Medical School, Baltimore, USA
| | - Robert Perneczky
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.,Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-Universität München, Munich, Germany.,Ageing Epidemiology (AGE) Research Unit, School of Public Health, Faculty of Medicine, The Imperial College of Science, Technology and Medicine, London, UK.,German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
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5269
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Leuzy A, Savitcheva I, Chiotis K, Lilja J, Andersen P, Bogdanovic N, Jelic V, Nordberg A. Clinical impact of [ 18F]flutemetamol PET among memory clinic patients with an unclear diagnosis. Eur J Nucl Med Mol Imaging 2019; 46:1276-1286. [PMID: 30915522 PMCID: PMC6486908 DOI: 10.1007/s00259-019-04297-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 02/25/2019] [Indexed: 12/11/2022]
Abstract
Purpose To investigate the impact of amyloid PET with [18F]flutemetamol on diagnosis and treatment management in a cohort of patients attending a tertiary memory clinic in whom, despite extensive cognitive assessment including neuropsychological testing, structural imaging, CSF biomarker analysis and in some cases [18F]FDG PET, the diagnosis remained unclear. Methods The study population consisted of 207 patients with a clinical diagnosis prior to [18F]flutemetamol PET including mild cognitive impairment (MCI; n = 131), Alzheimer’s disease (AD; n = 41), non-AD (n = 10), dementia not otherwise specified (dementia NOS; n = 20) and subjective cognitive decline (SCD; n = 5). Results Amyloid positivity was found in 53% of MCI, 68% of AD, 20% of non-AD, 20% of dementia NOS, and 60% of SCD patients. [18F]Flutemetamol PET led, overall, to a change in diagnosis in 92 of the 207 patients (44%). A high percentage of patients with a change in diagnosis was observed in the MCI group (n = 67, 51%) and in the dementia NOS group (n = 11; 55%), followed by the non-AD and AD (30% and 20%, respectively). A significant increase in cholinesterase inhibitor treatment was observed after [18F]flutemetamol PET (+218%, 34 patients before and 108 patients after). Conclusion The present study lends support to the clinical value of amyloid PET in patients with an uncertain diagnosis in the tertiary memory clinic setting.
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Affiliation(s)
- Antoine Leuzy
- Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics Center for Alzheimer Research, Karolinska Institutet, Neo, 7th floor, 141 83, Huddinge, Sweden
| | - Irina Savitcheva
- Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Konstantinos Chiotis
- Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics Center for Alzheimer Research, Karolinska Institutet, Neo, 7th floor, 141 83, Huddinge, Sweden
| | - Johan Lilja
- Department of Surgical Sciences, Radiology, Nuclear Medicine and PET, Uppsala University, Uppsala, Sweden.,Hermes Medical Solutions, Stockholm, Sweden
| | - Pia Andersen
- Clinic for Cognitive Disorders, Theme Aging, Karolinska University Hospital, Stockholm, Sweden
| | - Nenad Bogdanovic
- Clinic for Cognitive Disorders, Theme Aging, Karolinska University Hospital, Stockholm, Sweden
| | - Vesna Jelic
- Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics Center for Alzheimer Research, Karolinska Institutet, Neo, 7th floor, 141 83, Huddinge, Sweden.,Clinic for Cognitive Disorders, Theme Aging, Karolinska University Hospital, Stockholm, Sweden
| | - Agneta Nordberg
- Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics Center for Alzheimer Research, Karolinska Institutet, Neo, 7th floor, 141 83, Huddinge, Sweden. .,Clinic for Cognitive Disorders, Theme Aging, Karolinska University Hospital, Stockholm, Sweden.
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5270
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McCullough KC, Bayles KA, Bouldin ED. Language Performance of Individuals at Risk for Mild Cognitive Impairment. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2019; 62:706-722. [PMID: 30950734 DOI: 10.1044/2018_jslhr-l-18-0232] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Purpose Evidence exists that changes in language performance may be an early indicator of mild cognitive impairment (MCI), often a harbinger of dementing disease. The purpose of this study was the evaluation of language performance in individuals at risk for MCI by virtue of age and self-concern and its relation to performance on tests of memory, visuospatial function, and mental status. Method Eighty-three individuals 55 years or older were administered the Arizona Battery for Communication Disorders of Dementia ( Bayles & Tomoeda, 1993 ), a standardized battery with normative data from 86 healthy older adults (HOAs) and 86 individuals with Alzheimer's dementia, the most common dementing disease. A performance criterion of 1-1.5 SDs below the mean of HOAs defined MCI, as recommended in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. We hypothesized that (a) the majority of at-risk participants would score 1 SD or more below the mean of HOAs on 1 or more subtests and (b) language performance tests would present a greater challenge than memory, mental status, and visuospatial construction tests. Results Both hypotheses were confirmed. Sixty-two participants (74.6%) met the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria on at least 1 subtest. Moreover, language subtests were those most likely to elicit a performance 1 SD or more below the mean of HOAs. Conclusions Language performance deficits can appear early before impairment in episodic memory, visuospatial construction ability, or mental status in individuals at risk for MCI. Speech-language pathologists are uniquely qualified to identify subtle changes in language, and standardized language tests with normative data should be used when testing for MCI.
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Affiliation(s)
- Kim C McCullough
- Department of Communication Sciences and Disorders, Appalachian State University, Boone, NC
| | - Kathryn A Bayles
- Department of Speech, Language, and Hearing Sciences, University of Arizona, Tucson
| | - Erin D Bouldin
- Department of Health and Exercise Science, Appalachian State University, Boone, NC
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5271
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Conrad J, Kremmyda O, Högen T, Brendel M, Rominger A, Levin J, Danek A. [Posterior cortical atrophy-a heterogeneous syndrome : A case series]. DER NERVENARZT 2019; 90:1045-1050. [PMID: 30903200 DOI: 10.1007/s00115-019-0697-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Julian Conrad
- Klinik und Poliklinik für Neurologie, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, München, Deutschland.
- Deutsches Schwindel- und Gleichgewichtszentrum (DSGZ), Ludwig-Maximilians-Universität München, München, Deutschland.
| | - Olympia Kremmyda
- Klinik und Poliklinik für Neurologie, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, München, Deutschland
- Deutsches Schwindel- und Gleichgewichtszentrum (DSGZ), Ludwig-Maximilians-Universität München, München, Deutschland
| | - Tobias Högen
- Klinik und Poliklinik für Neurologie, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, München, Deutschland
| | - Matthias Brendel
- Klinik und Poliklinik für Nuklearmedizin, Ludwig-Maximilians-Universität München, München, Deutschland
| | - Axel Rominger
- Universitätsklinik für Nuklearmedizin, Inselspital, Universitätsspital Bern, Bern, Schweiz
| | - Johannes Levin
- Klinik und Poliklinik für Neurologie, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, München, Deutschland
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Feodor-Lynen-Straße 17, 81377, München, Deutschland
- Munich Cluster for Systems Neurology (SyNergy), München, Deutschland
| | - Adrian Danek
- Klinik und Poliklinik für Neurologie, Ludwig-Maximilians-Universität München, Marchioninistraße 15, 81377, München, Deutschland
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5272
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Zhao W, Wang X, Yin C, He M, Li S, Han Y. Trajectories of the Hippocampal Subfields Atrophy in the Alzheimer's Disease: A Structural Imaging Study. Front Neuroinform 2019; 13:13. [PMID: 30983985 PMCID: PMC6450438 DOI: 10.3389/fninf.2019.00013] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 02/19/2019] [Indexed: 11/13/2022] Open
Abstract
Background The hippocampus and hippocampal subfields have been found to be diversely affected in Alzheimer's Disease (AD) and early stages of Alzheimer's disease by neuroimaging studies. However, our knowledge is still lacking about the trajectories of the hippocampus and hippocampal subfields atrophy with the progression of Alzheimer's disease. Objective To identify which subfields of the hippocampus differ in the trajectories of Alzheimer's disease by magnetic resonance imaging (MRI) and to determine whether individual differences on memory could be explained by structural volumes of hippocampal subfields. Methods Four groups of participants including 41 AD patients, 43 amnestic mild cognitive impairment (aMCI) patients, 35 subjective cognitive decline (SCD) patients and 42 normal controls (NC) received their structural MRI brain scans. Structural MR images were processed by the FreeSurfer 6.0 image analysis suite to extract the hippocampus and its subfields. Furthermore, we investigated relationships between hippocampal subfield volumes and memory test variables (AVLT-immediate recall, AVLT-delayed recall, AVLT-recognition) and the regression model analyses were controlled for age, gender, education and eTIV. Results CA1, subiculum, presubiculum, molecular layer and fimbria showed the trend toward significant volume reduction among four groups with the progression of Alzheimer's disease. Volume of left subiculum was most strongly and actively correlated with performance across AVLT measures. Conclusion The trend changes in the hippocampus subfields and further illustrates that SCD is the preclinical stage of AD earlier than aMCI. Future studies should aim to associate the atrophy of the hippocampal subfields in SCD with possible conversion to aMCI or AD with longitudinal design.
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Affiliation(s)
- Weina Zhao
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China.,Department of Neurology, Mudanjiang Medical University Affiliated Hongqi Hospital, Mudanjiang, China
| | - Xuetong Wang
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
| | - Changhao Yin
- Department of Neurology, Mudanjiang Medical University Affiliated Hongqi Hospital, Mudanjiang, China
| | - Mengfei He
- Department of Neurology, Mudanjiang Medical University Affiliated Hongqi Hospital, Mudanjiang, China
| | - Shuyu Li
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China.,Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
| | - Ying Han
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China.,Institute of Alzheimer Disease, Beijing Institute for Brain Disorders, Beijing, China.,Institute of Geriatrics, Beijing Hospital, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China
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5273
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Salvadó G, Molinuevo JL, Brugulat-Serrat A, Falcon C, Grau-Rivera O, Suárez-Calvet M, Pavia J, Niñerola-Baizán A, Perissinotti A, Lomeña F, Minguillon C, Fauria K, Zetterberg H, Blennow K, Gispert JD. Centiloid cut-off values for optimal agreement between PET and CSF core AD biomarkers. Alzheimers Res Ther 2019; 11:27. [PMID: 30902090 PMCID: PMC6429814 DOI: 10.1186/s13195-019-0478-z] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 02/27/2019] [Indexed: 01/22/2023]
Abstract
BACKGROUND The Centiloid scale has been developed to standardize measurements of amyloid PET imaging. Reference cut-off values of this continuous measurement enable the consistent operationalization of decision-making for multicentre research studies and clinical trials. In this study, we aimed at deriving reference Centiloid thresholds that maximize the agreement against core Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers in two large independent cohorts. METHODS A total of 516 participants of the ALFA+ Study (N = 205) and ADNI (N = 311) underwent amyloid PET imaging ([18F]flutemetamol and [18F]florbetapir, respectively) and core AD CSF biomarker determination using Elecsys® tests. Tracer uptake was quantified in Centiloid units (CL). Optimal Centiloid cut-offs were sought that maximize the agreement between PET and dichotomous determinations based on CSF levels of Aβ42, tTau, pTau, and their ratios, using pre-established reference cut-off values. To this end, a receiver operating characteristic analysis (ROC) was conducted, and Centiloid cut-offs were calculated as those that maximized the Youden's J Index or the overall percentage agreement recorded. RESULTS All Centiloid cut-offs fell within the range of 25-35, except for CSF Aβ42 that rendered an optimal cut-off value of 12 CL. As expected, the agreement of tau/Aβ42 ratios was higher than that of CSF Aβ42. Centiloid cut-off robustness was confirmed even when established in an independent cohort and against variations of CSF cut-offs. CONCLUSIONS A cut-off of 12 CL matches previously reported values derived against postmortem measures of AD neuropathology. Together with these previous findings, our results flag two relevant inflection points that would serve as boundary of different stages of amyloid pathology: one around 12 CL that marks the transition from the absence of pathology to subtle pathology and another one around 30 CL indicating the presence of established pathology. The derivation of robust and generalizable cut-offs for core AD biomarkers requires cohorts with adequate representation of intermediate levels. TRIAL REGISTRATION ALFA+ Study, NCT02485730 ALFA PET Sub-study, NCT02685969.
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Affiliation(s)
- Gemma Salvadó
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
| | - José Luis Molinuevo
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
- CIBER Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
| | - Anna Brugulat-Serrat
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
| | - Carles Falcon
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
- CIBER de Bioengeniería, Biomateriales y Nanomedicina, Madrid, Spain
| | - Oriol Grau-Rivera
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
| | - Marc Suárez-Calvet
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
| | - Javier Pavia
- CIBER de Bioengeniería, Biomateriales y Nanomedicina, Madrid, Spain
- Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain
- Instititut d’Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | | | | | | | - Carolina Minguillon
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
- CIBER Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain
| | - Karine Fauria
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
- CIBER Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain
| | - Henrik Zetterberg
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
| | - Kaj Blennow
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Juan Domingo Gispert
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- CIBER de Bioengeniería, Biomateriales y Nanomedicina, Madrid, Spain
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5274
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Amyloid beta in nasal secretions may be a potential biomarker of Alzheimer's disease. Sci Rep 2019; 9:4966. [PMID: 30899050 PMCID: PMC6428828 DOI: 10.1038/s41598-019-41429-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 03/08/2019] [Indexed: 12/31/2022] Open
Abstract
We investigated the level of amyloid beta (Aβ) in nasal secretions of patients with Alzheimer’s disease dementia (ADD) using interdigitated microelectrode (IME) biosensors and determined the predictive value of Aβ in nasal secretions for ADD diagnosis. Nasal secretions were obtained from 35 patients with ADD, 18 with cognitive decline associated with other neurological disorders (OND), and 26 cognitively unimpaired (CU) participants. Capacitance changes in IMEs were measured by capturing total Aβ (ΔCtAβ). After 4-(2-hydroxyethyl)-1-piperazinepropanesulfonic acid (EPPS) was injected, additional capacitance changes due to the smaller molecular weight Aβ oligomers disassembled from the higher molecular weight oligomeric Aβ were determined (ΔCoAβ). By dividing two values, the capacitance ratio (ΔCoAβ/ΔCtAβ) was determined and then normalized to the capacitance change index (CCI). The CCI was higher in the ADD group than in the OND (p = 0.040) and CU groups (p = 0.007). The accuracy of the CCI was fair in separating into the ADD and CU groups (area under the receiver operating characteristic curve = 0.718, 95% confidence interval = 0.591–0.845). These results demonstrate that the level of Aβ in nasal secretions increases in ADD and the detection of Aβ in nasal secretions using IME biosensors may be possible in predicting ADD.
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5275
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Tang Y, Xing Y, Zhu Z, He Y, Li F, Yang J, Liu Q, Li F, Teipel SJ, Zhao G, Jia J. The effects of 7‐week cognitive training in patients with vascular cognitive impairment, no dementia (the Cog‐VACCINE study): A randomized controlled trial. Alzheimers Dement 2019; 15:605-614. [DOI: 10.1016/j.jalz.2019.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 12/26/2018] [Accepted: 01/09/2019] [Indexed: 10/27/2022]
Affiliation(s)
- Yi Tang
- Department of NeurologyXuanwu HospitalCapital Medical UniversityBeijingChina
- Innovation Center for Neurological DisordersXuanwu HospitalCapital Medical UniversityBeijingChina
- Key Laboratory of Neurodegenerative DiseasesMinistry of Education of the People's Republic of ChinaBeijingChina
| | - Yi Xing
- Department of NeurologyXuanwu HospitalCapital Medical UniversityBeijingChina
- Innovation Center for Neurological DisordersXuanwu HospitalCapital Medical UniversityBeijingChina
- Key Laboratory of Neurodegenerative DiseasesMinistry of Education of the People's Republic of ChinaBeijingChina
| | - Zude Zhu
- Collaborative Innovation Center for Language AbilityJiangsu Normal UniversityXuzhouChina
| | - Yong He
- State Key Laboratory of Cognitive Neuroscience and LearningBeijingChina
- Beijing Key Laboratory of Brain Imaging and ConnectomicsBeijingChina
- IDG/McGovern Institute for Brain ResearchBeijing Normal UniversityBeijingChina
| | - Fang Li
- Department of GeriatricFu Xing HospitalCapital Medical UniversityBeijingChina
| | - Jianwei Yang
- Department of NeurologyXuanwu HospitalCapital Medical UniversityBeijingChina
- Innovation Center for Neurological DisordersXuanwu HospitalCapital Medical UniversityBeijingChina
- Key Laboratory of Neurodegenerative DiseasesMinistry of Education of the People's Republic of ChinaBeijingChina
| | - Qing Liu
- Department of NeurologyXuanwu HospitalCapital Medical UniversityBeijingChina
- Innovation Center for Neurological DisordersXuanwu HospitalCapital Medical UniversityBeijingChina
| | - Fangyu Li
- Department of NeurologyXuanwu HospitalCapital Medical UniversityBeijingChina
- Innovation Center for Neurological DisordersXuanwu HospitalCapital Medical UniversityBeijingChina
- Key Laboratory of Neurodegenerative DiseasesMinistry of Education of the People's Republic of ChinaBeijingChina
| | - Stefan J. Teipel
- Department of Psychosomatic MedicineUniversity Medicine RostockRostockGermany
- DZNEGerman Center for Neurodegenerative DiseasesRostockGermany
| | - Guoguang Zhao
- Department of NeurosurgeryXuanwu HospitalCapital Medical UniversityBeijingChina
| | - Jianping Jia
- Department of NeurologyXuanwu HospitalCapital Medical UniversityBeijingChina
- Innovation Center for Neurological DisordersXuanwu HospitalCapital Medical UniversityBeijingChina
- Key Laboratory of Neurodegenerative DiseasesMinistry of Education of the People's Republic of ChinaBeijingChina
- Center of Alzheimer's DiseaseBeijing Institute for Brain DisordersBeijingChina
- Beijing Key Laboratory of Geriatric Cognitive DisordersBeijingChina
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5276
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Sadiki FZ, Idrissi ME, Cioanca O, Trifan A, Hancianu M, Hritcu L, Postu PA. Tetraclinis articulata essential oil mitigates cognitive deficits and brain oxidative stress in an Alzheimer's disease amyloidosis model. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2019; 56:57-63. [PMID: 30668354 DOI: 10.1016/j.phymed.2018.10.032] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 10/26/2018] [Accepted: 10/27/2018] [Indexed: 06/09/2023]
Abstract
BACKGROUND Tetraclinis articulata is used in traditional medicine and has been reported to possess antibacterial, antifungal, cytotoxic, anti-inflammatory and antioxidant properties. PURPOSE This study investigated the effects of T. articulata essential oil on memory and brain oxidative stress in amyloid-β peptide 1-42 (Aβ1-42)-induced an Alzheimer's disease amyloidosis model. Moreover, the underlying mechanism for memory enhancement and antioxidant activity was investigated, thus supporting its traditional use with scientific evidence for further studies. METHODS T. articulata essential oil was administered by inhalation to male Wistar rats once daily for 15 min period at doses of 1% and 3% for 21 days after the intracerebroventricular administration of Aβ1-42 right-unilaterally to induce memory deficits. The chemical composition of the essential oil was done by GC-MS and GC-FID. Spatial memory of rats was tested using Y-maze and radial arm maze tests. The possible underlying mechanism for memory improvement exhibited by T. articulata essential oil was investigated by in vivo brain antioxidant effect and acetylcholinesterase (AChE) inhibitory effect. In vitro, experimental evaluations were assessed through DPPH and ABTS tests. RESULTS The GC-MS and GC-FID data showed that the essential oil has a high percent of monoterpene hydrocarbons. Also, we demonstrated the essential oil reversed the Aβ1-42-induced decreasing of the spontaneous alternation in the Y-maze test and the Aβ1-42-induced increasing of the working and reference memory errors in the radial arm maze test. Furthermore, the Aβ1-42-decreased the acetylcholinesterase activity and the oxidant-antioxidant status in the rat hippocampus was retrieved by the treatment with the essential oil. CONCLUSION The study demonstrates that the essential oil could be a potent pharmacological agent against dementia by modulating cholinergic activity and promoting antioxidant action in the rat hippocampus.
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Affiliation(s)
- Fatima Zahra Sadiki
- Laboratory of Molecular Chemistry and Natural Substances, Department of Chemistry, Faculty of Sciences of Meknes, Moulay Ismail University, Bp. 11201, Zitoune, Meknès, Morocco
| | - Mostafa El Idrissi
- Laboratory of Molecular Chemistry and Natural Substances, Department of Chemistry, Faculty of Sciences of Meknes, Moulay Ismail University, Bp. 11201, Zitoune, Meknès, Morocco
| | - Oana Cioanca
- Department of Pharmacognosy, Faculty of Pharmacy, University of Medicine and Pharmacy "Gr. T. Popa", Iasi, Str. Universitatii, No. 16, 700115 Iasi, Romania
| | - Adriana Trifan
- Department of Pharmacognosy, Faculty of Pharmacy, University of Medicine and Pharmacy "Gr. T. Popa", Iasi, Str. Universitatii, No. 16, 700115 Iasi, Romania
| | - Monica Hancianu
- Department of Pharmacognosy, Faculty of Pharmacy, University of Medicine and Pharmacy "Gr. T. Popa", Iasi, Str. Universitatii, No. 16, 700115 Iasi, Romania
| | - Lucian Hritcu
- Department of Biology, Faculty of Biology, Alexandru Ioan Cuza University of Iasi, Bd. Carol I, No. 11, 700505 Iasi, Romania.
| | - Paula Alexandra Postu
- Department of Biology, Faculty of Biology, Alexandru Ioan Cuza University of Iasi, Bd. Carol I, No. 11, 700505 Iasi, Romania
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5277
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Ottoy J, Niemantsverdriet E, Verhaeghe J, De Roeck E, Struyfs H, Somers C, Wyffels L, Ceyssens S, Van Mossevelde S, Van den Bossche T, Van Broeckhoven C, Ribbens A, Bjerke M, Stroobants S, Engelborghs S, Staelens S. Association of short-term cognitive decline and MCI-to-AD dementia conversion with CSF, MRI, amyloid- and 18F-FDG-PET imaging. NEUROIMAGE-CLINICAL 2019; 22:101771. [PMID: 30927601 PMCID: PMC6444289 DOI: 10.1016/j.nicl.2019.101771] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/08/2019] [Accepted: 03/10/2019] [Indexed: 12/31/2022]
Abstract
Disease-modifying treatment trials are increasingly advanced to the prodromal or preclinical phase of Alzheimer's disease (AD), and inclusion criteria are based on biomarkers rather than clinical symptoms. Therefore, it is of great interest to determine which biomarkers should be combined to accurately predict conversion from mild cognitive impairment (MCI) to AD dementia. However, up to date, only few studies performed a complete A/T/N subject characterization using each of the CSF and imaging markers, or they only investigated long-term (≥ 2 years) prognosis. This study aimed to investigate the association between cerebrospinal fluid (CSF), magnetic resonance imaging (MRI), amyloid- and 18F-FDG positron emission tomography (PET) measures at baseline, in relation to cognitive changes and conversion to AD dementia over a short-term (12-month) period. We included 13 healthy controls, 49 MCI and 16 AD dementia patients with a clinical-based diagnosis and a complete A/T/N characterization at baseline. Global cortical amyloid-β (Aβ) burden was quantified using the 18F-AV45 standardized uptake value ratio (SUVR) with two different reference regions (cerebellar grey and subcortical white matter), whereas metabolism was assessed based on 18F-FDG SUVR. CSF measures included Aβ1–42, Aβ1–40, T-tau, P-tau181, and their ratios, and MRI markers included hippocampal volumes (HV), white matter hyperintensities, and cortical grey matter volumes. Cognitive functioning was measured by MMSE and RBANS index scores. All statistical analyses were corrected for age, sex, education, and APOE ε4 genotype. As a result, faster cognitive decline was most strongly associated with hypometabolism (posterior cingulate) and smaller hippocampal volume (e.g., Δstory recall: β = +0.43 [p < 0.001] and + 0.37 [p = 0.005], resp.) at baseline. In addition, faster cognitive decline was significantly associated with higher baseline Aβ burden only if SUVR was referenced to the subcortical white matter (e.g., Δstory recall: β = −0.28 [p = 0.020]). Patients with MCI converted to AD dementia at an annual rate of 31%, which could be best predicted by combining neuropsychological testing (visuospatial construction skills) with either MRI-based HV or 18F-FDG-PET. Combining all three markers resulted in 96% specificity and 92% sensitivity. Neither amyloid-PET nor CSF biomarkers could discriminate short-term converters from non-converters. FDG-PET and MRI HV are the strongest predictors of cognitive decline and conversion to AD. Combination of visuospatial construction testing with FDG-PET or MRI HV present high predicting power of conversion. CSF and amyloid-PET seem less suitable markers of disease progression. Increased AV45-PET predicts short-term cognitive decline if SUVR is referenced to WM instead of CB.
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Affiliation(s)
- Julie Ottoy
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
| | - Ellis Niemantsverdriet
- Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Jeroen Verhaeghe
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium
| | - Ellen De Roeck
- Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Hanne Struyfs
- Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Charisse Somers
- Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Leonie Wyffels
- Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Sarah Ceyssens
- Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Sara Van Mossevelde
- Neurodegenerative Brain Diseases Group, Center for Molecular Neurology, VIB, Antwerp, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Tobi Van den Bossche
- Neurodegenerative Brain Diseases Group, Center for Molecular Neurology, VIB, Antwerp, Belgium
| | - Christine Van Broeckhoven
- Neurodegenerative Brain Diseases Group, Center for Molecular Neurology, VIB, Antwerp, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | | | - Maria Bjerke
- Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Sigrid Stroobants
- Department of Nuclear Medicine, Antwerp University Hospital, Edegem, Belgium
| | - Sebastiaan Engelborghs
- Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Steven Staelens
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium.
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5278
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Farrar G, Molinuevo JL, Zanette M. Is there a difference in regional read [ 18F]flutemetamol amyloid patterns between end-of-life subjects and those with amnestic mild cognitive impairment? Eur J Nucl Med Mol Imaging 2019; 46:1299-1308. [PMID: 30863934 PMCID: PMC6486895 DOI: 10.1007/s00259-019-04282-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 02/04/2019] [Indexed: 02/04/2023]
Abstract
PURPOSE Visual interpretation of PET [18F]flutemetamol images relies on systematic review of five brain regions and is considered positive when an elevated signal is observed in at least one region. Amnestic mild cognitive impairment (aMCI) is an early clinical presentation of Alzheimer's disease (AD); hence it is of interest to determine if the pattern of visually read regional positivity between end-of-life (EoL) patients with and without dementia and aMCI patients is different. METHODS A total of 180 EoL patients with and without dementia (mean age 81 years, range 59 to 95 years) and 232 aMCI patients (mean age 71 years, range 53 to 91 years) were scanned following intravenous administration of 185-370 MBq [18F]flutemetamol. Images from both studies were read by two groups of five blinded readers who independently classified each of the five regions as either positive or negative. The majority interpretation made by at least three of the five readers was used as the imaging endpoint and compared with a composite standardized uptake value ratio (SUVR) analysis using a predetermined threshold. RESULTS Amyloid-positive images from 71 of 106 EoL patients coming to autopsy and from 97 aMCI patients were included. In the images from the EoL patients widespread deposition of amyloid was observed, with 76% of the images positive in all five regions and a further 20% positive in four regions. In the images from the aMCI patients, similar results were observed with 87% of the images positive in five regions and a further 5% positive in four regions. The mean SUVR of these positively read images was 2.24 (range 1.48 to 3.14) and 2.08 (range 1.28 to 3.04) in the autopsy and aMCI groups, respectively. There was 95.3% agreement between the visual reading and SUVR quantitation in the aMCI group and 90.4% agreement in the autopsy group. CONCLUSION Patients with aMCI showed a similar distribution of amyloid deposition determined by both visual reading and SUVR to that observed in patients with and without dementia coming to autopsy. Most of the aMCI patients, who are already within the AD continuum, had widespread amyloid deposition in terms of amount and topographical progression. Attempts to observe potential initial signs of amyloid deposition should focus on populations earlier in the dementia spectrum such as patients with subjective cognitive decline or even at-risk subjects with earlier stages of disease.
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Affiliation(s)
| | - José Luis Molinuevo
- Barcelona Beta Brain Research Center, Pasqual Maragall Foundation and Hospital Clinic I Universitari, IDIBAPS, Barcelona, Spain
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5279
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Paciotti S, Sepe FN, Eusebi P, Farotti L, Cataldi S, Gatticchi L, Parnetti L. Diagnostic performance of a fully automated chemiluminescent enzyme immunoassay for Alzheimer's disease diagnosis. Clin Chim Acta 2019; 494:74-78. [PMID: 30878539 DOI: 10.1016/j.cca.2019.03.1612] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/27/2019] [Accepted: 03/12/2019] [Indexed: 01/15/2023]
Abstract
The variability of Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers (Aβ42, t-Tau and p-Tau) undermines their full-fledged introduction into routine diagnostics and clinical trials. The introduction of automatic systems can improve the diagnostic performance promoting standardization and reducing the impact of preanalytical and analytical factors. Here we assessed the diagnostic performance of a fully automated chemiluminescent enzyme assay (LUMIPULSE) and compared it with that obtained by using the classical manual enzyme-linked immunosorbent assays (ELISAs). Patients were clinically diagnosed as AD (n = 42) and non-AD (n = 38). Clinical diagnosis was confirmed at follow-up. LUMIPULSE Aβ42 was reduced in AD (969.4 ± 329.6 pg/mL vs. 1625.9 ± 745.9 pg/mL, p <0.001), whereas LUMIPULSE t-Tau was increased in AD (768.2 ± 281.0 pg/mL vs. 337.5 ± 159.1 pg/mL, p < 0.001) compared to non-AD patients. Both LUMIPULSE Aβ42 (AUC = 0.78, spec. = 0.74, sens. = 0.76) and t-Tau (AUC = 0.94, spec. = 0.93, sens. = 0.87) showed good accuracy in distinguish AD from non-AD and a high correlation with the manual ELISAs (r = 0.87, p < 0.001 and r = 0.92, p < 0.001, respectively). LUMIPULSE improves clinical accuracy in AD diagnosis, promoting the use of standardized values for CSF biomarkers with a good correlation with classical manual assays.
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Affiliation(s)
- Silvia Paciotti
- Section of Physiology and Biochemistry, Department of Experimental Medicine, University of Perugia, Perugia, Italy; Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, S. Maria della Misericordia Hospital, Perugia, Italy.
| | - Federica N Sepe
- Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, S. Maria della Misericordia Hospital, Perugia, Italy
| | - Paolo Eusebi
- Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, S. Maria della Misericordia Hospital, Perugia, Italy
| | - Lucia Farotti
- Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, S. Maria della Misericordia Hospital, Perugia, Italy
| | - Samuela Cataldi
- Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, S. Maria della Misericordia Hospital, Perugia, Italy
| | - Leonardo Gatticchi
- Section of Physiology and Biochemistry, Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Lucilla Parnetti
- Laboratory of Clinical Neurochemistry, Department of Medicine, University of Perugia, S. Maria della Misericordia Hospital, Perugia, Italy.
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5280
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Skouras S, Falcon C, Tucholka A, Rami L, Sanchez-Valle R, Lladó A, Gispert JD, Molinuevo JL. Mechanisms of functional compensation, delineated by eigenvector centrality mapping, across the pathophysiological continuum of Alzheimer's disease. NEUROIMAGE-CLINICAL 2019; 22:101777. [PMID: 30913531 PMCID: PMC6434094 DOI: 10.1016/j.nicl.2019.101777] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 02/08/2019] [Accepted: 03/10/2019] [Indexed: 01/22/2023]
Abstract
Background Mechanisms of functional compensation throughout the progression of Alzheimer's disease (AD) remain largely underspecified. By investigating functional connectomics in relation to cerebrospinal fluid (CSF) biomarkers across the pathophysiological continuum of AD, we identify disease-stage-specific patterns of functional degradation and functional compensation. Methods Data from a sample of 96 participants, comprised of 49 controls, 11 preclinical AD subjects, 21 patients with mild cognitive impairment (MCI) due to AD and 15 patients with mild dementia due to AD, were analyzed. CSF ratio of phosphorylated tau protein over amyloid beta peptide 42 (p-tau/Aβ42) was computed and used as a marker of progression along the AD continuum. Whole-brain, voxel-wise eigenvector centrality mapping (ECM) was computed from resting-state fMRI and regression against p-tau/Aβ42 was performed. Surviving clusters were used as data-derived seeds in functional connectivity analyses and investigated in relation to memory performance scores (delayed free recall and memory alteration) via complementary regression models. To investigate disease-stage-specific effects, the whole-brain connectivity maps of each cluster were compared between progressive groups. Results Centrality in BA39-BA19 is negatively correlated with the p-tau/Aβ42 ratio and associated to memory function impairment across the AD continuum. The thalamus, anterior cingulate (ACC), midcingulate (MCC) and posterior cingulate cortex (PCC) show the opposite effect. The MCC shows the highest increase in centrality as memory performance decays. In the asymptomatic preclinical group, MCC shows reduced functional connectivity (FC) with the left hippocampus and stronger FC with the precuneus (PCu). Additionally, BA39-BA19 show reduced FC with the cerebellum, compensated by stronger FC between cerebellum and PCC. In the MCI group, PCC shows reduced FC with PCu, compensated by stronger FC with the left pars orbitalis, insula and temporal pole, as well as by stronger FC of MCC with its anterior and ventral neighboring areas and the cerebellum. In the mild dementia group, extensive functional decoupling occurs across the entire autobiographical memory network and functional resilience ensues in posterior regions and the cerebellum. Conclusions Functional decoupling in preclinical AD occurs predominantly in AD-vulnerable regions (e.g. hippocampus, cerebellar lobule VI / Crus I, visual cortex, frontal pole) and coupling between MCC and PCu, as well as between PCC and cerebellum, emerge as intrinsic mechanisms of functional compensation. At the MCI stage, the PCu can no longer compensate for hippocampal decoupling, but the compensatory role of the MCC and PCC ensue into the stage of dementia. These findings shed light on the neural mechanisms of functional compensation across the pathophysiological continuum of AD, highlighting the compensatory roles of several key brain areas. BA39-BA19 centrality implicated in Alzheimer's disease. Increasing centrality in cingulate and thalamus involved in functional compensation. Preclinical functional alterations of hippocampus compensated by precuneus. Cerebellar involvement in functional compensation.
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Affiliation(s)
- Stavros Skouras
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Spain
| | - Carles Falcon
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Spain; Biomateriales y Nanomedicina (CIBER-BBN), Centro de Investigación Biomédica en Red de Bioingeniería, Madrid, Spain
| | - Alan Tucholka
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Spain
| | - Lorena Rami
- Alzheimer's Disease and Other Cognitive Disorders Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Raquel Sanchez-Valle
- Alzheimer's Disease and Other Cognitive Disorders Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Albert Lladó
- Alzheimer's Disease and Other Cognitive Disorders Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Juan D Gispert
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Spain; Biomateriales y Nanomedicina (CIBER-BBN), Centro de Investigación Biomédica en Red de Bioingeniería, Madrid, Spain
| | - José Luís Molinuevo
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Spain; Alzheimer's Disease and Other Cognitive Disorders Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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5281
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Hwang J, Jeong JH, Yoon SJ, Park KW, Kim EJ, Yoon B, Jang JW, Kim HJ, Hong JY, Lee JM, Park H, Kang JH, Choi YH, Park G, Hong J, Byun MS, Yi D, Kim YK, Lee DY, Choi SH. Clinical and Biomarker Characteristics According to Clinical Spectrum of Alzheimer's Disease (AD) in the Validation Cohort of Korean Brain Aging Study for the Early Diagnosis and Prediction of AD. J Clin Med 2019; 8:jcm8030341. [PMID: 30862124 PMCID: PMC6463169 DOI: 10.3390/jcm8030341] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 03/04/2019] [Accepted: 03/07/2019] [Indexed: 01/09/2023] Open
Abstract
We aimed to present the study design of an independent validation cohort from the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's disease (AD) (KBASE-V) and to investigate the baseline characteristics of the participants according to the AD clinical spectrum. We recruited 71 cognitively normal (CN) participants, 96 with subjective cognitive decline (SCD), 72 with mild cognitive impairment (MCI), and 56 with AD dementia (ADD). The participants are followed for three years. The Consortium to Establish a Registry for AD scores was significantly different between all of the groups. The logical memory delayed recall scores were significantly different between all groups, except between the MCI and ADD groups. The Mini-Mental State Examination score, hippocampal volume, and cerebrospinal fluid (CSF) amyloid-β42 level were significant difference among the SCD, MCI, and ADD groups. The frequencies of participants with amyloid pathology according to PET or CSF studies were 8.9%, 25.6%, 48.3%, and 90.0% in the CN, SCD, MCI, and ADD groups, respectively. According to ATN classification, A+/T+/N+ or A+/T+/N- was observed in 0%, 15.5%, 31.0%, and 78.3% in the CN, SCD, MCI, and ADD groups, respectively. The KBASE-V showed a clear difference according to the AD clinical spectrum in neuropsychological tests and AD biomarkers.
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Affiliation(s)
- Jihye Hwang
- Department of Neurology, Keimyung University Dongsan Medical Center, Daegu 41931, Korea.
| | - Jee Hyang Jeong
- Department of Neurology, Ewha Womans University School of Medicine, Seoul 07985, Korea.
| | - Soo Jin Yoon
- Department of Neurology, Eulji University School of Medicine, Daejeon 35233, Korea.
| | - Kyung Won Park
- Department of Neurology, Dong-A Medical Center, Dong-A University College of Medicine, Busan 49201, Korea.
| | - Eun-Joo Kim
- Department of Neurology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan 49241, Korea.
| | - Bora Yoon
- Department of Neurology, Konyang University College of Medicine, Daejeon 35365, Korea.
| | - Jae-Won Jang
- Department of Neurology, Kangwon National University Hospital, Kangwon National University College of Medicine, Chuncheon 24289, Korea.
| | - Hee Jin Kim
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea.
| | - Jin Yong Hong
- Department of Neurology, Yonsei University Wonju College of Medicine, Wonju 26426, Korea.
| | - Jong-Min Lee
- Department of Biomedical Engineering, Hanyang University, Seoul 04763, Korea.
| | - Hyuntae Park
- Department of Health Care and Science, Dong-A University, Busan 49315, Korea.
| | - Ju-Hee Kang
- Department of Pharmacology, Inha University School of Medicine, Incheon 22212, Korea.
| | - Yong-Ho Choi
- Department of Biomedical Engineering, Hanyang University, Seoul 04763, Korea.
| | - Gilsoon Park
- Department of Biomedical Engineering, Hanyang University, Seoul 04763, Korea.
| | - Jinwoo Hong
- Department of Biomedical Engineering, Hanyang University, Seoul 04763, Korea.
| | - Min Soo Byun
- Institute of Human Behavioral Medicine, Medical Research Center Seoul National University, Seoul 03080, Korea.
| | - Dahyun Yi
- Institute of Human Behavioral Medicine, Medical Research Center Seoul National University, Seoul 03080, Korea.
| | - Yu Kyeong Kim
- Department of Nuclear Medicine, SMG-SNU Boramae Medical Center, Seoul 07061, Korea.
| | - Dong Young Lee
- Department of Neuropsychiatry, Seoul National University Hospital & Department of Seoul National University College of Medicine, Seoul 03080, Korea.
| | - Seong Hye Choi
- Department of Neurology, Inha University School of Medicine, Incheon 22332, Korea.
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5282
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Kirsebom BE, Espenes R, Hessen E, Waterloo K, Johnsen SH, Gundersen E, Botne Sando S, Rolfseng Grøntvedt G, Timón S, Fladby T. Demographically adjusted CERAD wordlist test norms in a Norwegian sample from 40 to 80 years. Clin Neuropsychol 2019; 33:27-39. [DOI: 10.1080/13854046.2019.1574902] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Bjørn-Eivind Kirsebom
- Department of Neurology, University Hospital of North Norway, Tromsø, Norway
- Department of Psychology Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Ragna Espenes
- Department of Neurology, University Hospital of North Norway, Tromsø, Norway
- Department of Psychology Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Erik Hessen
- Department of Neurology, Akershus University Hospital, Lørenskog, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Knut Waterloo
- Department of Neurology, University Hospital of North Norway, Tromsø, Norway
- Department of Psychology Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Stein Harald Johnsen
- Department of Neurology, University Hospital of North Norway, Tromsø, Norway
- Department of Clinical Medicine, Brain and Circulation Research Group, UiT The Arctic University of Norway, Tromsø, Norway
| | - Elisabeth Gundersen
- Department of Neurology, University Hospital of North Norway, Tromsø, Norway
- Department of Psychology Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Sigrid Botne Sando
- Department of Neuromedicine and Movement Science Faculty of Medicine and Health, Sciences Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, University Hospital of Trondheim, Trondheim, Norway
| | - Gøril Rolfseng Grøntvedt
- Department of Neuromedicine and Movement Science Faculty of Medicine and Health, Sciences Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, University Hospital of Trondheim, Trondheim, Norway
| | - Santiago Timón
- Department of Neurology, Akershus University Hospital, Lørenskog, Norway
- Departamento de Inteligencia Artificial Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - Tormod Fladby
- Department of Neurology, Akershus University Hospital, Lørenskog, Norway
- Institute of Clinical Medicine, Campus Ahus, University of Oslo, Oslo, Norway
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5283
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Amyloid PET and cognitive decline in cognitively normal individuals: the SCIENCe project. Neurobiol Aging 2019; 79:50-58. [PMID: 31026622 DOI: 10.1016/j.neurobiolaging.2019.02.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 02/08/2019] [Accepted: 02/27/2019] [Indexed: 12/18/2022]
Abstract
We examined the relationships between amyloid-β PET and concurrent and longitudinal cognitive performance in 107 cognitively normal individuals with subjective cognitive decline (age: 64 ± 8 years, 44% female, Mini-Mental State Examination score 29 ± 1). All underwent 90-minute dynamic [18F]florbetapir PET scanning and longitudinal neuropsychological tests with a mean follow-up of 3.4 ± 3.0 years. Receptor parametric mapping was used to calculate [18F]florbetapir binding potential (BPND), and we performed linear mixed models to assess the relationships between global [18F]florbetapir BPND and neuropsychological performance. Higher [18F]florbetapir BPND was related to lower concurrent Mini-Mental State Examination (β ± SE: -1.69 ± 0.63 p < 0.01) and to steeper rate of decline on tasks capturing memory (Rey Auditory Verbal Learning Task immediate [β ± SE -1.81 ± 0.81, p < 0.05] and delayed recall [β ± SE -1.19 ± 0.34, p < 0.01]), attention/executive functions (Stroop II [color] [β ± SE -0.02 ± 0.01, p < 0.05], Stroop III [word-color] [β ± SE -0.03 ± 0.02, p < 0.05]), and language (category fluency [β ± SE -0.04 ± 0.01, p < 0.01]). These findings suggest that higher amyloid-β load in cognitively normal individuals with subjective cognitive decline from a memory clinic is associated with lower concurrent global cognition and with faster rate of decline in a variety of cognitive domains.
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5284
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Association of Glucose Fluctuations with Sarcopenia in Older Adults with Type 2 Diabetes Mellitus. J Clin Med 2019; 8:jcm8030319. [PMID: 30845785 PMCID: PMC6463152 DOI: 10.3390/jcm8030319] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 02/27/2019] [Accepted: 02/28/2019] [Indexed: 12/16/2022] Open
Abstract
Type 2 diabetes mellitus accelerates loss of muscle mass and strength. Patients with Alzheimer’s disease (AD) also show these conditions, even in the early stages of AD. The mechanism linking glucose management with these muscle changes has not been elucidated but has implications for clarifying these associations and developing preventive strategies to maintain functional capacity. This study included 69 type 2 diabetes patients with a diagnosis of cognitive impairment (n = 32) and patients with normal cognition (n = 37). We investigated the prevalence of sarcopenia in diabetes patients with and without cognitive impairment and examined the association of glucose alterations with sarcopenia. Daily glucose levels were evaluated using self-monitoring of blood glucose, and we focused on the effects of glucose fluctuations, postprandial hyperglycemia, and the frequency of hypoglycemia on sarcopenia. Diabetes patients with cognitive impairment displayed a high prevalence of sarcopenia, and glucose fluctuations were independently associated with sarcopenia, even after adjusting for glycated hemoglobin A1c (HbA1c) levels and associated factors. In particular, glucose fluctuations were significantly associated with a low muscle mass, low grip strength, and slow walking speed. Our observation suggests the importance of glucose management by considering glucose fluctuations to prevent the development of disability.
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5285
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Vos SJB, Duara R. The prognostic value of ATN Alzheimer biomarker profiles in cognitively normal individuals. Neurology 2019; 92:643-644. [PMID: 30842299 DOI: 10.1212/wnl.0000000000007223] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Affiliation(s)
- Stephanie J B Vos
- From the Department of Psychiatry and Neuropsychology (S.J.B.V.), School for Mental Health and NeuroScience, Alzheimer Center Limburg, Maastricht University, the Netherlands; Wien Center for Alzheimer's Disease and Memory Disorders (R.D.), Mount Sinai Medical Center, Miami Beach; and Department of Neurology (R.D.), University of Florida College of Medicine, Gainesville.
| | - Ranjan Duara
- From the Department of Psychiatry and Neuropsychology (S.J.B.V.), School for Mental Health and NeuroScience, Alzheimer Center Limburg, Maastricht University, the Netherlands; Wien Center for Alzheimer's Disease and Memory Disorders (R.D.), Mount Sinai Medical Center, Miami Beach; and Department of Neurology (R.D.), University of Florida College of Medicine, Gainesville
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5286
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Soldan A, Pettigrew C, Fagan AM, Schindler SE, Moghekar A, Fowler C, Li QX, Collins SJ, Carlsson C, Asthana S, Masters CL, Johnson S, Morris JC, Albert M, Gross AL. ATN profiles among cognitively normal individuals and longitudinal cognitive outcomes. Neurology 2019; 92:e1567-e1579. [PMID: 30842300 DOI: 10.1212/wnl.0000000000007248] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 11/27/2018] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVE To examine the long-term cognitive trajectories of individuals with normal cognition at baseline and distinct amyloid/tau/neurodegeneration (ATN) profiles. METHODS Pooling data across 4 cohort studies, 814 cognitively normal participants (mean baseline age = 59.6 years) were classified into 8 ATN groups using baseline CSF levels of β-amyloid 1-42 as a measure of amyloid (A), phosphorylated tau 181 as a measure of tau (T), and total tau as a measure of neurodegeneration (N). Cognitive performance was measured using a previously validated global factor score and with the Mini-Mental State Examination. We compared the cognitive trajectories across groups using growth curve models (mean follow-up time = 7 years). RESULTS Using different model formulations and cut points for determining biomarker abnormality, only the group with abnormal levels of amyloid, tau, and neurodegeneration (A+T+N+) showed consistently greater cognitive decline than the group with normal levels of all biomarkers (A-T-N-). Replicating prior findings using the 2011 National Institute on Aging-Alzheimer's Association/suspected non-Alzheimer disease pathophysiology schema, only individuals with abnormal levels of both amyloid and phosphorylated tau 181 or total tau (stage 2) showed greater cognitive decline than those with normal biomarker levels (stage 0). CONCLUSION The results are consistent with the hypothesis that both elevated brain amyloid and neurofibrillary tangles are necessary to observe accelerated neurodegeneration, which in turn leads to cognitive decline.
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Affiliation(s)
- Anja Soldan
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD.
| | - Corinne Pettigrew
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Anne M Fagan
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Suzanne E Schindler
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Abhay Moghekar
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Christopher Fowler
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Qiao-Xin Li
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Steven J Collins
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Cynthia Carlsson
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Sanjay Asthana
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Colin L Masters
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Sterling Johnson
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - John C Morris
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Marilyn Albert
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Alden L Gross
- From the Department of Neurology (A.S., C.P., A.M., M.A.), Johns Hopkins University School of Medicine, Baltimore, MD; Department of Neurology (A.M.F., S.E.S., J.C.M.), Washington University School of Medicine, St. Louis, MO; Florey Institute of Neuroscience and Mental Health (C.F., Q.-X.L., S.J.C., C.L.M.), the University of Melbourne, Australia; Geriatric Research Education and Clinical Center (C.C., S.A., S.J.), Wm. S. Middleton Memorial VA Hospital and Department of Medicine, University of Wisconsin School of Medicine and Public Health, Madison; and Center on Aging and Health and Department of Epidemiology (A.L.G.), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
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5287
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Hofmann W, Wille E, Kaminsky S. [Guideline-conform exact diagnosis and coding of dementia]. Z Gerontol Geriatr 2019; 52:179-194. [PMID: 30830315 DOI: 10.1007/s00391-019-01509-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 01/11/2019] [Accepted: 01/17/2019] [Indexed: 11/24/2022]
Abstract
All of the currently available guidelines specify a two-stage procedure. The first stage entails performing a comprehensive description, diagnosis and confirmation of the dementia syndrome. The second stage involves the precise etiological classification. Alzheimer's disease represents the most common cause followed by vascular dementia and Parkinson's disease dementia, Lewy body dementia, frontotemporal lobar degeneration and others. Dementia encompasses a variety of underlying conditions. This review gives an overview of the clinically oriented diagnosis according to the updated S3 guidelines in Germany.
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Affiliation(s)
- W Hofmann
- Geriatrisches Zentrum Neumünster & Bad Bramstedt, Friesenstr. 11, 24534, Neumünster, Deutschland. .,Institut für Allgemeinmedizin, Campus Lübeck, Universitätsklinikum Schleswig-Holstein (UKSH), Lübeck, Deutschland.
| | - E Wille
- FEK Friedrich-Ebert-Krankenhaus Neumünster GmbH, Neumünster, Deutschland
| | - S Kaminsky
- Geriatrisches Zentrum Neumünster & Bad Bramstedt, Friesenstr. 11, 24534, Neumünster, Deutschland
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5288
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Martí-Juan G, Sanroma G, Piella G. Revealing heterogeneity of brain imaging phenotypes in Alzheimer's disease based on unsupervised clustering of blood marker profiles. PLoS One 2019; 14:e0211121. [PMID: 30830917 PMCID: PMC6398858 DOI: 10.1371/journal.pone.0211121] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 01/08/2019] [Indexed: 01/02/2023] Open
Abstract
Alzheimer's disease (AD) affects millions of people and is a major rising problem in health care worldwide. Recent research suggests that AD could have different subtypes, presenting differences in how the disease develops. Characterizing those subtypes could be key to deepen the understanding of this complex disease. In this paper, we used a multivariate, non-supervised clustering method over blood-based markers to find subgroups of patients defined by distinctive blood marker profiles. Our analysis on ADNI database identified 4 possible subgroups, each with a different blood profile. More importantly, we show that subgroups with different profiles have a different relationship between brain phenotypes detected in magnetic resonance imaging and disease condition.
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Affiliation(s)
- Gerard Martí-Juan
- BCN Medtech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Spain
| | - Gerard Sanroma
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Gemma Piella
- BCN Medtech, Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Spain
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5289
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Zecca C, Brescia V, Piccininni M, Capozzo R, Barone R, Barulli MR, Logroscino G. Comparative evaluation of two immunoassays for cerebrospinal fluid β-Amyloid 1-42 measurement. Clin Chim Acta 2019; 493:107-111. [PMID: 30844363 DOI: 10.1016/j.cca.2019.02.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 02/03/2019] [Accepted: 02/28/2019] [Indexed: 10/27/2022]
Abstract
AIM OF THE STUDY Beta-Amyloid 1-42 peptide (βA42) is a cerebro-spinal fluid (CSF) biomarker, key element of the NIA Alzheimer's disease diagnostic criteria. The enzyme-linked immunosorbent assay (ELISA) has been the mainstay method for βA42 measurement on cerebrospinal fluid (CSF). Recently, a new βA42 measurement method in chemiluminescence enzyme immunoassay (CLEIA) is available on Lumipulse G 600 II automatic platform. The aim of the work was to evaluate the concordance of the ELISA and the new method (CLEIA) in the CSF βA42 levels measurement. MATERIALS AND METHODS CSF βA42 levels were assayed in 49 samples using the ELISA method (Innotest β- amyloid 1-42, Fujirebio Europe N.V., Gent, Belgium) and CLEIA method on Lumipulse G600II fully automatic platform (Lumipulse G β- amyloid 1-42, Fujirebio Europe N.V., Gent, Belgium). We compared values of the two methods using acceptability interval based on Inherent Combined Imprecision (ICI), the Passing-Bablok regression analysis, the Pearson correlation coefficient (r) and the Bland-Altman plot. RESULTS The analysis of the ICI showed that the two methods differ substantially. The regression equation (y = -103.04 + 1.52×) highlighted the presence of proportional systematic difference, without significant deviation from linearity (p = .42). The Pearson correlation coefficient was 0.826. The Bland-Altman plot analysis showed a significant systematic difference in the two methods: ELISA measurements were in average -27.06% (95% CI -31.89 to -22.23%) lower compared to CLEIA ones. CONCLUSIONS Our study highlighted a difference between the two methods. Therefore, the cut-off for the normal levels of βA42 should be reviewed in the laboratory report.
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Affiliation(s)
- Chiara Zecca
- Center for Neurodegenerative Diseases and the Aging Brain, Department of Clinical Research in Neurology, University of Bari Aldo Moro, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy; Unit of Laboratory Medicine, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy.
| | - Vincenzo Brescia
- Unit of Laboratory Medicine, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy
| | - Marco Piccininni
- Center for Neurodegenerative Diseases and the Aging Brain, Department of Clinical Research in Neurology, University of Bari Aldo Moro, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy; Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Rosa Capozzo
- Center for Neurodegenerative Diseases and the Aging Brain, Department of Clinical Research in Neurology, University of Bari Aldo Moro, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy
| | - Roberta Barone
- Center for Neurodegenerative Diseases and the Aging Brain, Department of Clinical Research in Neurology, University of Bari Aldo Moro, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy
| | - Maria Rosaria Barulli
- Center for Neurodegenerative Diseases and the Aging Brain, Department of Clinical Research in Neurology, University of Bari Aldo Moro, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy
| | - Giancarlo Logroscino
- Center for Neurodegenerative Diseases and the Aging Brain, Department of Clinical Research in Neurology, University of Bari Aldo Moro, Pia Fondazione Cardinale G Panico, Tricase, Lecce, Italy; Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Bari, Italy.
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5290
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Alzheimer's Disease Diagnosis Based on Cortical and Subcortical Features. JOURNAL OF HEALTHCARE ENGINEERING 2019; 2019:2492719. [PMID: 30944718 PMCID: PMC6421724 DOI: 10.1155/2019/2492719] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 09/08/2018] [Accepted: 02/13/2019] [Indexed: 01/18/2023]
Abstract
Alzheimer's disease (AD) is a common neurodegenerative disease with an often seen prodromal mild cognitive impairment (MCI) phase, where memory loss is the main complaint progressively worsening with behavior issues and poor self-care. However, not all patients clinically diagnosed with MCI progress to the AD. Currently, several high-dimensional classification techniques have been developed to automatically distinguish among AD, MCI, and healthy control (HC) patients based on T1-weighted MRI. However, these method features are based on wavelets, contourlets, gray-level co-occurrence matrix, etc., rather than using clinical features which helps doctors to understand the pathological mechanism of the AD. In this study, a new approach is proposed using cortical thickness and subcortical volume for distinguishing binary and tertiary classification of the National Research Center for Dementia dataset (NRCD), which consists of 326 subjects. Five classification experiments are performed: binary classification, i.e., AD vs HC, HC vs mAD (MCI due to the AD), and mAD vs aAD (asymptomatic AD), and tertiary classification, i.e., AD vs HC vs mAD and AD vs HC vs aAD using cortical and subcortical features. Datasets were divided in a 70/30 ratio, and later, 70% were used for training and the remaining 30% were used to get an unbiased estimation performance of the suggested methods. For dimensionality reduction purpose, principal component analysis (PCA) was used. After that, the output of PCA was passed to various types of classifiers, namely, softmax, support vector machine (SVM), k-nearest neighbors, and naïve Bayes (NB) to check the performance of the model. Experiments on the NRCD dataset demonstrated that the softmax classifier is best suited for the AD vs HC classification with an F1 score of 99.06, whereas for other groups, the SVM classifier is best suited for the HC vs mAD, mAD vs aAD, and AD vs HC vs mAD classifications with the F1 scores being 99.51, 97.5, and 99.99, respectively. In addition, for the AD vs HC vs aAD classification, NB performed well with an F1 score of 95.88. In addition, to check our proposed model efficiency, we have also used the OASIS dataset for comparing with 9 state-of-the-art methods.
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5291
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Abstract
Within aging societies, the number of individuals suffering from Alzheimer disease (AD) is constistently increasing. This is paralleled by intense research aimed at improving treatment options and potentially even fostering effective prevention. The discussion on relevant outcomes of such interventions is ongoing. Here, different types of currently applied outcomes in the treatment of AD at the dementia stage, but also at the pre-dementia stages of mild cognitive impairment (MCI) and asymptomatic preclinical AD are discussed. Regulatory agencies require effects on the clinical measures of cognition and function. In novel disease-modifying therapy trials, biological markers are used as secondary and exploratory outcomes. Additional outcomes of great relevance for the individual patients are neuropsychiatric symptoms, quality of life, and goal attainment. In addition, costs and cost-benefit ratios are of interest for the reimbursement of interventions.
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Affiliation(s)
- Frank Jessen
- Department of Psychiatry, University of Cologne, Medical Faculty, Cologne, Germany
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5292
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Abstract
PURPOSE OF REVIEW This review presents the latest developments covered in the literature regarding psychosis in neurodegenerative disorders and discusses possible future research directions. RECENT FINDINGS Recent findings in the field of psychosis and neurodegenerative disorders revolve around four main themes. The first theme is the impact of sex on the expression of psychosis in neurodegenerative disorders. The second theme focuses on the relationship between psychosis and neurodegenerative disease biomarkers. The third concerns how psychotic symptoms in neurodegenerative disorders may share common mechanisms with other primary psychotic disorders such as schizophrenia. Finally, there have been some promising developments in the area of therapeutics to treat dementia-related psychosis involving both established and novel treatments. SUMMARY New findings in the field of neurodegeneration and psychosis parallel new directions in the field of neurodegeneration in general. More specifically, we have seen a shift in focus to issues highlighting the role of sex, biomarkers, translation to other disorders, and therapeutics.
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5293
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Wang M, Qin L, Tang B. MicroRNAs in Alzheimer's Disease. Front Genet 2019; 10:153. [PMID: 30881384 PMCID: PMC6405631 DOI: 10.3389/fgene.2019.00153] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Accepted: 02/13/2019] [Indexed: 12/22/2022] Open
Abstract
Alzheimer’s disease (AD) is a progressive and devastating neurodegenerative disorder. It is the leading cause of dementia in the world’s rapidly growing aging population. The characteristics of AD are memory loss and cognitive impairment, meaning patients cannot carry out their daily activities independently. The increase of AD cases poses heavy burdens on families, society and the economy. Despite frequent efforts being made to research the etiology of AD, the causes of AD remain unknown, and no curative treatments are available yet. The pathological hallmarks of AD are amyloid plaques and neurofibrillary tangles in the brain. MicroRNAs are endogenous ∼22 nucleotides non-coding RNAs that could regulate gene expression at a post-transcriptional level by transcript degradation or translation repression. MicroRNAs are involved in many biological processes and diseases, particularly multifactorial diseases, providing an excellent tool with which to research the mechanisms of these diseases. AD is a multifactorial disorder, and accumulating evidence shows that microRNAs play a critical role in the pathogenesis of AD. In this review, we will highlight the effect of microRNAs in different pathological processes throughout AD progression.
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Affiliation(s)
- Mengli Wang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Lixia Qin
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,Laboratory of Medical Genetics, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China.,Parkinson's Disease Center of Beijing Institute for Brain Disorders, Beijing, China
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5294
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Abstract
Similar to other complex disorders, the etiology of Alzheimer disease is multifactorial and characterized by an interplay of biological and environmental risk and protective factors. Potentially modifiable risk factors have emerged from epidemiological research and strategies to prevent neurodegeneration and dementia are currently being tested, including multimodal interventions aiming to reduce several risk factors at once. The concept of reserve was developed based on the observation that certain individual characteristics, such as life experiences, lifestyles, and neurobiological parameters, are associated with a higher resilience against neurodegeneration and its symptoms. Coordinated research is required to maximize the use of available human and financial resources to better understand the underlying neurobiological mechanisms of reserve and to translate research findings into effective public health interventions.
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5295
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Abstract
Given current lack of therapies for dementia, there is substantial interest in identifying potentially modifiable risk factors. Clarifying the potential of these factors to mitigate risk as well as determining the mechanisms that link these factors to dementia is expected to lead to new approaches for both preventing and treating neurodegenerative diseases such as Alzheimer disease. Modifiable factors include cardiovascular risks as well as related lifestyle-centric factors such as diet and physical activity (reviewed in this issue). Given reports that type 2 diabetes and associated features increase the risk for developing dementia, there has been tremendous interest in exploring whether use of antidiabetic medications may impact the risk of dementia, as well as whether antidiabetic medications could be used to prevent or treat dementia, particularly Alzheimer disease. This review will briefly cover the known links between diabetes and risk for dementia, the state of evidence linking antidiabetic treatments with either protection against dementia or possibly increased risk for cognitive dysfunction, and provide a brief overview of what has been learned from clinical trials testing antidiabetic treatments in Alzheimer disease.
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5296
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McCleery J, Flicker L, Richard E, Quinn TJ. When is Alzheimer's not dementia-Cochrane commentary on The National Institute on Ageing and Alzheimer's Association Research Framework for Alzheimer's Disease. Age Ageing 2019; 48:174-177. [PMID: 30329009 DOI: 10.1093/ageing/afy167] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 09/21/2018] [Indexed: 12/27/2022] Open
Abstract
Early 2018 saw the release of new diagnostic guidance on Alzheimer's disease from the National Institute on Ageing and the Alzheimer's Association (NIA-AA). This proposed research framework represents a fundamental change in how we think about Alzheimer's disease, moving from diagnosis based on clinical features to diagnosis based solely on biomarkers. These recommendations are contentious and have important implications for patients, clinicians, policy makers and the pharmaceutical industry. In this commentary, we offer a summary of the NIA-AA research framework. We then focus on five key areas: divorcing neuropathology from the clinical syndrome; the emphasis placed on one dementia subtype; validity of available biomarkers; the changing meaning of the term 'Alzheimer's disease'; and the potential for a research framework to influence clinical practice.
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Affiliation(s)
- Jenny McCleery
- Cochrane Dementia and Cognitive Improvement Group, University of Oxford, UK
| | - Leon Flicker
- Cochrane Dementia and Cognitive Improvement Group, University of Oxford, UK
- Western Australia Centre for Health & Ageing, University of Western Australia, Perth, Australia
| | - Edo Richard
- Cochrane Dementia and Cognitive Improvement Group, University of Oxford, UK
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, Netherlands
| | - Terence J Quinn
- Cochrane Dementia and Cognitive Improvement Group, University of Oxford, UK
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
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5297
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Brief cognitive screening instruments for early detection of Alzheimer's disease: a systematic review. ALZHEIMERS RESEARCH & THERAPY 2019; 11:21. [PMID: 30819244 PMCID: PMC6396539 DOI: 10.1186/s13195-019-0474-3] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVES The objective of this systematic review was (1) to give an overview of the available short screening instruments for the early detection of Alzheimer's disease (AD) and (2) to review the psychometric properties of these instruments. METHODS First, a systematic search of titles and abstracts of PubMed and Web of Science was conducted between February and July 2015 and updated in April 2016 and May 2018. Only papers written in English or Dutch were considered. All full-text papers about cognitive screening instruments for the early detection of AD were included, resulting in the identification of 38 pencil and paper tests and 12 computer tests. In a second step, the psychometric quality of these instruments was evaluated. Therefore, the same databases were searched again to identify papers that described the psychometric properties of the instruments meanwhile applying diagnostic criteria for the diagnostic groups included. RESULTS Out of 1454 papers, 96 clearly discussed the psychometric properties of the instruments. Eighty-nine papers discussed pencil and paper tests of which 80 were validated in a memory clinic setting. Based on the number of studies (31 articles) and the sensitivity (84%) and specificity (74%) values, the Montreal Cognitive Assessment (MoCA) seems to be a promising (pencil and paper) screening test for memory clinic testing as well as for population screening. Regarding computer tests, validation studies were only available for 7 out of 12 tests. CONCLUSIONS A large number of screening tests for AD are available. However, most tests are only validated in a memory clinic setting and description of the psychometric properties of the instruments is limited. Especially, computer tests require further research. The MoCA is a promising instrument, but the specificity to detect early AD is rather low.
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5298
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Perneczky R, Kempermann G, Korczyn AD, Matthews FE, Ikram MA, Scarmeas N, Chetelat G, Stern Y, Ewers M. Translational research on reserve against neurodegenerative disease: consensus report of the International Conference on Cognitive Reserve in the Dementias and the Alzheimer's Association Reserve, Resilience and Protective Factors Professional Interest Area working groups. BMC Med 2019; 17:47. [PMID: 30808345 PMCID: PMC6391801 DOI: 10.1186/s12916-019-1283-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 02/06/2019] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND The concept of reserve was established to account for the observation that a given degree of neurodegenerative pathology may result in varying degrees of symptoms in different individuals. There is a large amount of evidence on epidemiological risk and protective factors for neurodegenerative diseases and dementia, yet the biological mechanisms that underpin the protective effects of certain lifestyle and physiological variables remain poorly understood, limiting the development of more effective preventive and treatment strategies. Additionally, different definitions and concepts of reserve exist, which hampers the coordination of research and comparison of results across studies. DISCUSSION This paper represents the consensus of a multidisciplinary group of experts from different areas of research related to reserve, including clinical, epidemiological and basic sciences. The consensus was developed during meetings of the working groups of the first International Conference on Cognitive Reserve in the Dementias (24-25 November 2017, Munich, Germany) and the Alzheimer's Association Reserve and Resilience Professional Interest Area (25 July 2018, Chicago, USA). The main objective of the present paper is to develop a translational perspective on putative mechanisms underlying reserve against neurodegenerative disease, combining evidence from epidemiological and clinical studies with knowledge from animal and basic research. The potential brain functional and structural basis of reserve in Alzheimer's disease and other brain disorders are discussed, as well as relevant lifestyle and genetic factors assessed in both humans and animal models. CONCLUSION There is an urgent need to advance our concept of reserve from a hypothetical model to a more concrete approach that can be used to improve the development of effective interventions aimed at preventing dementia. Our group recommends agreement on a common dictionary of terms referring to different aspects of reserve, the improvement of opportunities for data sharing across individual cohorts, harmonising research approaches across laboratories and groups to reduce heterogeneity associated with human data, global coordination of clinical trials to more effectively explore whether reducing epidemiological risk factors leads to a reduced burden of neurodegenerative diseases in the population, and an increase in our understanding of the appropriateness of animal models for reserve research.
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Affiliation(s)
- Robert Perneczky
- Division of Mental Health in Older Adults and Alzheimer Therapy and Research Center, Department of Psychiatry and Psychotherapy, University Hospital, Ludwig Maximilian University Munich, 80336, Munich, Germany. .,German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany. .,Ageing Epidemiology (AGE) Research Unit, School of Public Health, Imperial College London, London, UK. .,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
| | - Gerd Kempermann
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Dresden, Germany.,Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
| | - Amos D Korczyn
- Sackler School of Medicine, Tel- Aviv University, Ramat Aviv, Israel
| | - Fiona E Matthews
- Institute of Health and Society, Newcastle University Institute for Ageing, Newcastle University, Newcastle, UK.,MRC Biostatistics Unit, Cambridge University, Cambridge, UK
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Nikolaos Scarmeas
- Department of Social Medicine, Psychiatry and Neurology, 1st Department of Neurology, Aeginition University Hospital, National and Kapodistrian University of Athens, Athens, Greece.,Cognitive Neuroscience Division, Department of Neurology and The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Gael Chetelat
- Université Normandie, Inserm, Université de Caen-Normandie, Inserm UMR-S U1237, GIP Cyceron, Caen, France
| | - Yaakov Stern
- Cognitive Neuroscience Division, Department of Neurology and The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY, USA
| | - Michael Ewers
- Institute for Stroke and Dementia Research, University Hospital, LMU Munich, Munich, Germany
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5299
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Watson J, Saunders S, Muniz Terrera G, Ritchie C, Evans A, Luz S, Clarke C. What matters to people with memory problems, healthy volunteers and health and social care professionals in the context of developing treatment to prevent Alzheimer's dementia? A qualitative study. Health Expect 2019; 22:504-517. [PMID: 30809895 PMCID: PMC6543163 DOI: 10.1111/hex.12876] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/17/2019] [Accepted: 02/02/2019] [Indexed: 01/09/2023] Open
Abstract
Background Alzheimer's disease (AD) is recognized as one of the greatest global public health challenges. There is increasing consensus that optimal disease modification using pharmaceuticals may best be achieved earlier in the disease continuum before symptoms occur. However, more needs to be understood about what outcomes are meaningful to potential participants in clinical trials within this preventative paradigm and how people make trade‐offs between risks and benefits. The Electronic Person‐Specific Outcome Measure (ePSOM) programme is developing an app to capture person‐specific outcomes and preferences in clinical trials. Objective As one phase in the ePSOM programme, this study explored what matters when developing new treatments to prevent AD and how trade‐offs are made between risks and benefits, from three perspectives. Design Focus groups were conducted with people living with memory problems (n = 21) and healthy volunteers (n = 10), and telephone interviews with health and social care professionals (n = 10). Differences and overlap between the three groups were explored. Results Outcomes that matter lie in five key domains in relation to what matters in everyday life: Everyday Functioning; Relationships and Social Connections; Enjoying Life; Sense of Identity; and Alleviating Symptoms. Insights were gained into the significance of reducing the risk of developing dementia with drugs and the processes of weighing up risks versus benefits. Discussion and conclusions The key domains identified are being used to inform the next stage of the ePSOM programme which is to develop a survey to be distributed nationally in the UK to explore these issues further.
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Affiliation(s)
- Julie Watson
- Edinburgh Centre for Research on the Experience of Dementia (ECRED), School of Health in Social Science, University of Edinburgh, Edinburgh, UK
| | - Stina Saunders
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Craig Ritchie
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Saturnino Luz
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK.,Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, UK
| | - Charlotte Clarke
- Edinburgh Centre for Research on the Experience of Dementia (ECRED), School of Health in Social Science, University of Edinburgh, Edinburgh, UK
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5300
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Schneider JA, Viswanathan A. The time for multiple biomarkers in studies of cognitive aging and dementia is now. Neurology 2019; 92:551-552. [DOI: 10.1212/wnl.0000000000007120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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