Agreement between cerebrospinal fluid biomarkers and Amyloid PET in a multicentric cohort

Background Cerebrospinal fluid (CSF) biomarkers have shown incomplete concordance with amyloid-positron emission tomography (PET). Our goal was to analyze the agreement between CSF and amyloid-PET in a multicenter study. Method Retrospective study (6 centers). Participants who underwent both maximum time tests <18 months were included. Biomarkers considered abnormal according cut points of each center, describing different ATN profiles: A+T+N+, A-T-N-, others. Amyloid-PET classified as positive/negative visually. Agreement analyzed by overall percent (OPA). Result 256 participants included (age 68(SD9), MMSE score 25(SD4)). Diagnoses mild cognitive impairment or dementia due Alzheimer’s disease (49%), Lewy body (21%), frontotemporal (10%) others (20%). Mean 4.9 (SD4,0). 41% APOEε4 carriers. Innotest® (32%) Lumipulse® (68%). PET tracers employed 18F-Florbetapir (71%), 18F-Flutemetamol (21%) 18F-Florbetaben (8%). OPA single 75% for Aβ1-42, pTau181, 74% tTau. The use Aβ1-42/Aβ1-40 ratio (n = 155) an indicator amyloid deposition increased (86%). other biomarker ratios also improved OPA: 88% pTau181/Aβ1-42 82% tTau/Aβ1-42). higher A+T+N+/A-T-N- cases (94%), mainly when all altered (97%). Conclusion their amyloid-PET. profiles had than 90%.