19
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Cerebrospinal fluid biomarkers in Alzheimer's disease: Diagnostic accuracy and prediction of dementia

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Introduction

          Guidelines for the use of cerebrospinal fluid (CSF) biomarkers in the diagnosis of Alzheimer's disease (AD) establish that each laboratory must use internally qualified cutoff values. We determined the concentrations of biomarkers that discriminate cases from controls and combinations that predict the progression to dementia in a Brazilian cohort.

          Methods

          Concentrations of amyloid-beta peptide (Aβ 1–42), total tau (T-tau), and 181Thr-phosphorylated-tau (P-tau) were determined in CSF samples from 184 older adults (68 mild cognitive impairment, 41 AD, 34 non-AD cognitive impairment, and 41 controls) by the INNO-BIA AlzBio3 assay.

          Results

          Cutoff values discriminating AD from controls are as follows: Aβ 1–42: 416.0 pg/mL (sensitivity [SE]: 83%, specificity (SP): 70%); T-tau: 76.7 pg/mL (SE: 82%, SP: 67%); P-tau: 36.1 pg/mL (SE: 83%, SP: 49%); Aβ 1–42/P-tau <9.53 (SE: 88%, SP: 78%); and Aβ 1–42/T-tau <4.13 (SE: 80%; SP: 80%). Combining values Aβ 1–42 <416.5 pg/mL and Aβ 1–42/P-tau <9.5 best predicted the conversion in 2 years (Cox regression: hazard ratio 7.24 [2.09–25.06], P = .002, SE: 74%, Sp: 73%).

          Discussion

          Our findings are in line with most of the available evidence in this field; yet, our cutoff values are different from those derived from other laboratories.

          Related collections

          Most cited references23

          • Record: found
          • Abstract: found
          • Article: not found

          Cerebrospinal fluid protein biomarkers for Alzheimer's disease.

          The introduction of acetylcholine esterase (AChE) inhibitors as a symptomatic treatment of Alzheimer's disease (AD) has made patients seek medical advice at an earlier stage of the disease. This has highlighted the importance of diagnostic markers for early AD. However, there is no clinical method to determine which of the patients with mild cognitive impairment (MCI) will progress to AD with dementia, and which have a benign form of MCI without progression. In this paper, the performance of cerebrospinal fluid (CSF) protein biomarkers for AD is reviewed. The diagnostic performance of the three biomarkers, total tau, phospho-tau, and the 42 amino acid form of beta-amyloid have been evaluated in numerous studies and their ability to identify incipient AD in MCI cases has also been studied. Some candidate AD biomarkers including ubiquitin, neurofilament proteins, growth-associated protein 43 (neuromodulin), and neuronal thread protein (AD7c) show interesting results but have been less extensively studied. It is concluded that CSF biomarkers may have clinical utility in the differentiation between AD and several important differential diagnoses, including normal aging, depression, alcohol dementia, and Parkinson's disease, and also in the identification of Creutzfeldt-Jakob disease in cases with rapidly progressive dementia. Early diagnosis of AD is not only of importance to be able to initiate symptomatic treatment with AChE inhibitors, but will be the basis for initiation of treatment with drugs aimed at slowing down or arresting the degenerative process, such as gamma-secretase inhibitors, if these prove to affect AD pathology and to have a clinical effect.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            The Alzheimer's Disease Neuroimaging Initiative: a review of papers published since its inception.

            The Alzheimer's Disease Neuroimaging Initiative (ADNI) is an ongoing, longitudinal, multicenter study designed to develop clinical, imaging, genetic, and biochemical biomarkers for the early detection and tracking of Alzheimer's disease (AD). The study aimed to enroll 400 subjects with early mild cognitive impairment (MCI), 200 subjects with early AD, and 200 normal control subjects; $67 million funding was provided by both the public and private sectors, including the National Institute on Aging, 13 pharmaceutical companies, and 2 foundations that provided support through the Foundation for the National Institutes of Health. This article reviews all papers published since the inception of the initiative and summarizes the results as of February 2011. The major accomplishments of ADNI have been as follows: (1) the development of standardized methods for clinical tests, magnetic resonance imaging (MRI), positron emission tomography (PET), and cerebrospinal fluid (CSF) biomarkers in a multicenter setting; (2) elucidation of the patterns and rates of change of imaging and CSF biomarker measurements in control subjects, MCI patients, and AD patients. CSF biomarkers are consistent with disease trajectories predicted by β-amyloid cascade (Hardy, J Alzheimers Dis 2006;9(Suppl 3):151-3) and tau-mediated neurodegeneration hypotheses for AD, whereas brain atrophy and hypometabolism levels show predicted patterns but exhibit differing rates of change depending on region and disease severity; (3) the assessment of alternative methods of diagnostic categorization. Currently, the best classifiers combine optimum features from multiple modalities, including MRI, [(18)F]-fluorodeoxyglucose-PET, CSF biomarkers, and clinical tests; (4) the development of methods for the early detection of AD. CSF biomarkers, β-amyloid 42 and tau, as well as amyloid PET may reflect the earliest steps in AD pathology in mildly symptomatic or even nonsymptomatic subjects, and are leading candidates for the detection of AD in its preclinical stages; (5) the improvement of clinical trial efficiency through the identification of subjects most likely to undergo imminent future clinical decline and the use of more sensitive outcome measures to reduce sample sizes. Baseline cognitive and/or MRI measures generally predicted future decline better than other modalities, whereas MRI measures of change were shown to be the most efficient outcome measures; (6) the confirmation of the AD risk loci CLU, CR1, and PICALM and the identification of novel candidate risk loci; (7) worldwide impact through the establishment of ADNI-like programs in Europe, Asia, and Australia; (8) understanding the biology and pathobiology of normal aging, MCI, and AD through integration of ADNI biomarker data with clinical data from ADNI to stimulate research that will resolve controversies about competing hypotheses on the etiopathogenesis of AD, thereby advancing efforts to find disease-modifying drugs for AD; and (9) the establishment of infrastructure to allow sharing of all raw and processed data without embargo to interested scientific investigators throughout the world. The ADNI study was extended by a 2-year Grand Opportunities grant in 2009 and a renewal of ADNI (ADNI-2) in October 2010 through to 2016, with enrollment of an additional 550 participants. Copyright © 2013 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Improved discrimination of AD patients using beta-amyloid(1-42) and tau levels in CSF.

              To evaluate CSF levels of beta-amyloid(1-42) (Abeta42) alone and in combination with CSF tau for distinguishing AD from other conditions. At 10 centers in Europe and the United States, 150 CSF samples from AD patients were analyzed and compared with 100 CSF samples from healthy volunteers or patients with disorders not associated with pathologic conditions of the brain (CON), 84 patients with other neurologic disorders (ND), and 79 patients with non-Alzheimer types of dementia (NAD). Sandwich ELISA techniques were used on site for measuring Abeta42 and tau. Median levels of Abeta42 in CSF were significantly lower in AD (487 pg/mL) than in CON (849 pg/mL; p = 0.001), ND (643 pg/mL; p = 0.001), and NAD (603 pg/mL; p = 0.001). Discrimination of AD from CON and ND was significantly improved by the combined assessment of Abeta42 and tau. At 85% sensitivity, specificity of the combined test was 86% (95% CI: 81% to 91%) compared with 55% (95% CI: 47% to 62%) for Abeta42 alone and 65% (95% CI: 58% to 72%) for tau. The combined test at 85% sensitivity was 58% (95% CI: 47% to 69%) specific for NAD. The APOE e4 gene load was negatively correlated with Abeta42 levels not only in AD but also in NAD. The combined measure of CSF Abeta42 and tau meets the requirements for clinical use in discriminating AD from normal aging and specific neurologic disorders.
                Bookmark

                Author and article information

                Contributors
                Journal
                Alzheimers Dement (Amst)
                Alzheimers Dement (Amst)
                Alzheimer's & Dementia : Diagnosis, Assessment & Disease Monitoring
                Elsevier
                2352-8729
                03 October 2015
                December 2015
                03 October 2015
                : 1
                : 4
                : 455-463
                Affiliations
                [a ]Laboratory of Neuroscience (LIM-27), Department and Institute of Psychiatry, Faculty of Medicine, University of Sao Paulo, Sao Paulo, SP, Brazil
                [b ]Department of Mental Health, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
                [c ]Clinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
                [d ]UCL Institute of Neurology, London, UK
                Author notes
                []Corresponding author. Tel.: +55-11-2661-7283; Fax: +55-11-2661-7535. forlenza@ 123456usp.br
                Article
                S2352-8729(15)00073-1
                10.1016/j.dadm.2015.09.003
                4879480
                27239524
                1b922d50-d424-4aeb-a479-7fa05fdeb3a4
                © 2015 The Authors

                This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

                Categories
                CSF Biomarkers

                alzheimer's disease,mild cognitive impairment,amyloid-β,tau protein,biomarkers,cerebrospinal fluid

                Comments

                Comment on this article