Plasma Oligomer β-Amyloid and White Matter Microstructural Integrity in Cognitively Normal Older Adults According to Cerebral Amyloid Deposition

Background Multimer detection system-oligomeric amyloid-β (MDS-OAβ) measure plasma OAβ level, which is associated with earlier Alzheimer’s disease (AD) pathology. However, no study has investigated MDS-OAβ differences in cognitive normal older adults (CN) with or without cerebral Aβ burden and its correlation with Aβ deposition and white matter (WM) integrity. Objective To investigate associations among cerebral Aβ burden, MDS-OAβ, and WM integrity in CN. Design This is a single center, cross-sectional study which used data from Catholic Aging Brain Imaging (CABI) database. Setting CABI database contains brain scans of patients who visited the outpatient clinic at Catholic Brain Health Center, Yeouido St. Mary’s Hospital, The Catholic University of Korea, between 2017 and 2022. Participants A total 34 amyloid-PET negative CN and 23 amyloid-PET positive CN were included. Measurements Plasma Aβ level using MDS-OAβ, cerebral Aβ deposition level using global standardized uptake value ratio (SUVR) values, WM integrity using fractional anisotropy (FA) and mean diffusivity (MD), and cortical thickness from structural MRI were utilized. Restuls The amyloid-PET positive group showed higher MDS-OAβ level than the amyloid-PET negative group (0.997 ± 0.19 vs. 0.79 ± 0.28, P