Diagnostic performance of plasma pTau217, pTau181, Aß1-42 and Aß1-40 in the LUMIPULSE automated platform for the detection of Alzheimer disease.
Alzheimers Res Ther
; 16(1): 139, 2024 06 26.
Article
in En
| MEDLINE
| ID: mdl-38926773
ABSTRACT
BACKGROUND:
Recently developed blood markers for Alzheimer's disease (AD) detection have high accuracy but usually require ultra-sensitive analytic tools not commonly available in clinical laboratories, and their performance in clinical practice is unknown.METHODS:
We analyzed plasma samples from 290 consecutive participants that underwent lumbar puncture in routine clinical practice in a specialized memory clinic (66 cognitively unimpaired, 130 participants with mild cognitive impairment, and 94 with dementia). Participants were classified as amyloid positive (A +) or negative (A-) according to CSF Aß1-42/Aß1-40 ratio. Plasma pTau217, pTau181, Aß1-42 and Aß1-40 were measured in the fully-automated LUMIPULSE platform. We used linear regression to compare plasma biomarkers concentrations between A + and A- groups, evaluated Spearman's correlation between plasma and CSF and performed ROC analyses to assess their diagnostic accuracy to detect brain amyloidosis as determined by CSF Aß1-42/Aß1-40 ratio. We analyzed the concordance of pTau217 with CSF amyloidosis.RESULTS:
Plasma pTau217 and pTau181 concentration were higher in A + than A- while the plasma Aß1-42/Aß1-40 ratio was lower in A + compared to A-. pTau181 and the Aß1-42/Aß1-40 ratio showed moderate correlation between plasma and CSF (Rho = 0.66 and 0.69, respectively). The areas under the ROC curve to discriminate A + from A- participants were 0.94 (95% CI 0.92-0.97) for pTau217, and 0.88 (95% CI 0.84-0.92) for both pTau181 and Aß1-42/Aß1-40. Chronic kidney disease (CKD) was related to increased plasma biomarker concentrations, but ratios were less affected. Plasma pTau217 had the highest fold change (× 3.2) and showed high predictive capability in discriminating A + from A-, having 4-7% misclassification rate. The global accuracy of plasma pTau217 using a two-threshold approach was robust in symptomatic groups, exceeding 90%.CONCLUSION:
The evaluation of blood biomarkers on an automated platform exhibited high diagnostic accuracy for AD pathophysiology, and pTau217 showed excellent diagnostic accuracy to identify participants with AD in a consecutive sample representing the routine clinical practice in a specialized memory unit.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Peptide Fragments
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Biomarkers
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Amyloid beta-Peptides
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Tau Proteins
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Alzheimer Disease
Limits:
Aged
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Aged80
/
Female
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Humans
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Male
/
Middle aged
Language:
En
Journal:
Alzheimers Res Ther
Year:
2024
Document type:
Article