RESUMEN
BACKGROUND: ß-amyloid (Aß) positron emission tomography (PET) imaging is currently the only Food and Drug Administration-approved method to support clinical diagnosis of Alzheimer's disease (AD). However, numerous research studies support the use of cerebrospinal fluid (CSF) biomarkers, as a cost-efficient, quick and equally valid method to define AD pathology. METHODS: Using automated Elecsys® assays (Roche Diagnostics) for Aß (1-42) (Aß42), Aß (1-40) (Aß40), total tau (tTau) and phosphorylated tau (181P) (pTau), we examined CSF samples from 202 participants of the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of ageing cohort, to demonstrate the concordance with pathological AD via PET imaging. RESULTS: Ratios Aß42/Aß40, tTau/Aß42 and pTau/Aß42 had higher receiver operator characteristic-area under the curve (all 0.94), and greater concordance with Aß-PET (overall percentage agreement ~ 90%), compared with individual biomarkers. CONCLUSION: Strong concordance between CSF biomarkers and Aß-PET status was observed overall, including for cognitively normal participants, further strengthening the association between these markers of AD neuropathological burden for both developmental research studies and for use in clinical trials.