Plasma Aβ42/40 ratio alone or combined with FDG-PET can accurately predict amyloid-PET positivity : A cross-sectional analysis from the AB255 Study
Pérez-Grijalba, Virginia (Araclon Biotech S.L.)
Arbizu, Javier (Clínica Universidad de Navarra)
Romero, Judith (Araclon Biotech S.L.)
Prieto, Elena (Clínica Universidad de Navarra)
Pesini, Pedro (Araclon Biotech S.L.)
Sarasa, Leticia (Araclon Biotech S.L.)
Guillen, Fernando (Clínica Universidad de Navarra)
Monleón, Inmaculada (Araclon Biotech S.L.)
San-José, Itziar (Araclon Biotech S.L.)
Martínez-Lage, Pablo (Fundación CITA-Alzheimer)
Munuera, Josep (Institut de Recerca Sant Joan de Déu)
Hernández, Isabel (Instituto de Salud Carlos III)
Buendía, Mar (Universitat Internacional de Catalunya)
Sotolongo-Grau, Oscar (Universitat Internacional de Catalunya)
Alegret, Montserrat (Instituto de Salud Carlos III)
Ruiz, Agustín (Instituto de Salud Carlos III)
Tárraga, Lluís (Instituto de Salud Carlos III)
Boada, Mercè (Instituto de Salud Carlos III)
Sarasa, Manuel (Araclon Biotech S.L.)
Goñi Imízcoz, Miguel (Hospital Divino Vallés (Burgos))
Pujadas, Francesc
Villarejo, Alberto
Frank, Ana
Peña-Casanova, Jordi
Fernández, Manuel
Piñol, Gerard
Blesa, Rafael (Institut d'Investigació Biomèdica Sant Pau)
Gil, Pedro
Pascual, Luis F.
Aguilar Barberà, Miquel
Frisoni, Giovanni B.
Matias-Guiu, Jorge
Andreasen, Niels
Antúnez, Carmen
Universitat Autònoma de Barcelona

Date:	2019
Abstract:	To facilitate population screening and clinical trials of disease-modifying therapies for Alzheimer's disease, supportive biomarker information is necessary. This study was aimed to investigate the association of plasma amyloid-beta (Aβ) levels with the presence of pathological accumulation of Aβ in the brain measured by amyloid-PET. Both plasma Aβ42/40 ratio alone or combined with an FDG-PET-based biomarker of neurodegeneration were assessed as potential AD biomarkers. We included 39 cognitively normal subjects and 20 patients with mild cognitive impairment from the AB255 Study who had undergone PiB-PET scans. Total Aβ40 and Aβ42 levels in plasma (TP42/40) were quantified using ABtest kits. Subjects were dichotomized as Aβ-PET positive or negative, and the ability of TP42/40 to detect Aβ-PET positivity was assessed by logistic regression and receiver operating characteristic analyses. Combination of plasma Aβ biomarkers and FDG-PET was further assessed as an improvement for brain amyloidosis detection and diagnosis classification. Eighteen (30. 5%) subjects were Aβ-PET positive. TP42/40 ratio alone identified Aβ-PET status with an area under the curve (AUC) of 0. 881 (95% confidence interval [CI] = 0. 779-0. 982). Discriminating performance of TP42/40 to detect Aβ-PET-positive subjects yielded sensitivity and specificity values at Youden's cutoff of 77. 8% and 87. 5%, respectively, with a positive predictive value of 0. 732 and negative predictive value of 0. 900. All these parameters improved after adjusting the model for significant covariates. Applying TP42/40 as the first screening tool in a sequential diagnostic work-up would reduce the number of Aβ-PET scans by 64%. Combination of both FDG-PET scores and plasma Aβ biomarkers was found to be the most accurate Aβ-PET predictor, with an AUC of 0. 965 (95% CI = 0. 913-0. 100). Plasma TP42/40 ratio showed a relevant and significant potential as a screening tool to identify brain Aβ positivity in preclinical and prodromal stages of Alzheimer's disease.
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Amyloid-beta ; Amyloid-PET ; Biomarker ; FDG-PET ; Mild cognitive impairment ; Plasma ; Preclinical Alzheimer's disease
Published in:	Alzheimer's research & therapy, Vol. 11 Núm. 1 (january 2019) , p. 96, ISSN 1758-9193

DOI: 10.1186/s13195-019-0549-1
PMID: 31787105

9 p, 1012.4 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Health sciences and biosciences > Institut de Recerca Sant Pau
Articles > Research articles
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