%0 Journal Article %J J Alzheimers Dis %D 2017 %T The Cerebrospinal Fluid Aβ1-42/Aβ1-40 Ratio Improves Concordance with Amyloid-PET for Diagnosing Alzheimer's Disease in a Clinical Setting. %A Niemantsverdriet, Ellis %A Ottoy, Julie %A Somers, Charisse %A De Roeck, Ellen %A Struyfs, Hanne %A Soetewey, Femke %A Verhaeghe, Jeroen %A Van den Bossche, Tobi %A Van Mossevelde, Sara %A Goeman, Johan %A De Deyn, Peter Paul %A Mariën, Peter %A Versijpt, Jan %A Sleegers, Kristel %A Van Broeckhoven, Christine %A Wyffels, Leonie %A Albert, Adrien %A Ceyssens, Sarah %A Stroobants, Sigrid %A Staelens, Steven %A Bjerke, Maria %A Engelborghs, Sebastiaan %X

BACKGROUND: Evidence suggests that the concordance between amyloid-PET and cerebrospinal fluid (CSF) amyloid-β (Aβ) increases when the CSF Aβ1-42/Aβ1-40 ratio is used as compared to CSF Aβ1-42 levels alone.

OBJECTIVE: In order to test this hypothesis, we set up a prospective longitudinal study comparing the concordance between different amyloid biomarkers for Alzheimer's disease (AD) in a clinical setting.

METHODS: Seventy-eight subjects (AD dementia (n = 17), mild cognitive impairment (MCI, n = 48), and cognitively healthy controls (n = 13)) underwent a [18F]Florbetapir ([18F]AV45) PET scan, [18F]FDG PET scan, MRI scan, and an extensive neuropsychological examination. In a large subset (n = 67), a lumbar puncture was performed and AD biomarkers were analyzed (Aβ1-42, Aβ1-40, T-tau, P-tau181).

RESULTS: We detected an increased concordance in the visual and quantitative (standardized uptake value ratio (SUVR) and total volume of distribution (VT)) [18F]AV45 PET measures when the CSF Aβ1-42/Aβ1-40 was applied compared to Aβ1-42 alone. CSF biomarkers were stronger associated to [18F]AV45 PET for SUVR values when considering the total brain white matter as reference region instead of cerebellar grey matterConclusions:The concordance between CSF Aβ and [18F]AV45 PET increases when the CSF Aβ1-42/Aβ1-40 ratio is applied. This finding is of most importance for the biomarker-based diagnosis of AD as well as for selection of subjects for clinical trials with potential disease-modifying therapies for AD.

%B J Alzheimers Dis %V 60 %P 561-576 %8 2017 %G eng %N 2 %R 10.3233/JAD-170327