Related Experiment Video
Updated: Oct 26, 2026
Full- versus Sub-Regional Quantification of Amyloid-Beta Load on Mouse Brain Sections
Published on: May 19, 2022
A data-driven regional amyloid PET score predicts cognitive decline beyond Centiloid
Background:
The Centiloid (CL) scale standardizes global amyloid PET quantification and is widely used to define amyloid positivity. As a global summary measure, however, CL may not fully reflect the regional distribution of amyloid deposition, which can carry additional prognostic information about the rate of cognitive decline.
Objective:
To develop and externally validate a fixed, regional amyloid PET composite score that complements CL for predicting cognitive decline in Alzheimer's disease.
Methods:
The Regional Amyloid PET Score (RAPS) was derived from 82 FreeSurfer regions using machine learning with bootstrap stability selection to predict the rate of change in CDR-Sum of Boxes (CDR-SB) in 433 amyloid-positive ADNI [ 18 F]florbetapir participants. The fixed nine-region weights were applied without retraining in a cross-tracer ADNI [ 18 F]florbetaben subset ( N = 71; largely overlapping the discovery participants) and two external validation cohorts, NACC SCAN ( N = 1531; four tracers) and OASIS-3 ( N = 428).
Results:
RAPS comprised nine regions. In ADNI, RAPS correlated more strongly with CDR-SB slope than CL and showed higher discrimination of rapid decliners (AUC 0.813 vs 0.713). Performance was directionally consistent across validation cohorts; in NACC SCAN, RAPS and CL independently predicted clinical progression. Cross-cohort meta-analysis of the three independent cohorts supported incremental discrimination beyond CL (pooled ΔAUC +0.066; I 2 = 0%).
Conclusions:
RAPS, a fixed regional amyloid PET-derived score, may complement CL for prognostic stratification in Alzheimer's disease research.
