Igor Yakushev, Germany
Klinikum rechts der Isar, Technical University of Munich, School of Medicine Department of Nuclear MedicineAuthor Of 1 Presentation
ELECSYS CSF ASSAYS ACCURATELY DETECT ALZHEIMER’S DISEASE REGARDLESS OF CONCOMITANT SMALL VESSEL DISEASE
Abstract
Aims
Differentiating dementia due to small vessel disease (SVD) from Alzheimer’s disease (AD) with concomitant SVD is not optimized in clinical practice; impaired cerebral drainage due to SVD may alter cerebrospinal fluid (CSF) biomarker levels. We aimed to clarify accuracy of CSF biomarkers in patients with AD and concomitant SVD.
Methods
CSF samples from 84 patients with early AD (mild cognitive impairment [n=26]; mild dementia [n=58]) were measured by Elecsys® CSF immunoassays (Roche Diagnostics). SVD was assessed by the extent of white matter hyperintensities (WMH) on three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging using the lesion segmentation tool (LST). Spearman correlation coefficients between WMH and CSF biomarkers, age, mini-mental state examinations (MMSE) and clinical dementia rating--sum of boxes scores (CDR-SOB) were calculated. Sensitivity and specificity of Elecsys CSF immunoassays using Elecsys package inserts with AD typical metabolic pattern in fluorodeoxyglucose-positron emission tomography (FDG-PET) as comparator (58% AD-positive) were calculated for low, medium and high WMH.
Results
Observed correlations with WMH (*indicates p<0.05) were: Aβ42/Aβ40 (rho=-0.25*), tTau (0.30*), tTau/Aβ42 (0.25*), pTau (0.22), pTau/Aβ42 (0.23), age (0.37*) and MMSE (0.41*), and CDR-SOB (0.23). Sensitivity and specificity stratified by WMH tertile remained within the confidence intervals (CI) for the group point estimate (Table).
Conclusions
The results of this study demonstrate that performance of Elecsys CSF immunoassays to detect AD is not affected by concomitant SVD. Hence, Elecsys CSF assays may support clinicians in differentiating patients with SVD versus AD with concomitant SVD.