Is Amyloid Burden Measured by 18F-Flutemetamol PET Associated with Progression in Clinical Alzheimer’s Disease?

Abstract

Background: Patients with Alzheimer’s disease (AD) show heterogeneity in clinical progression rate, and we have limited tools to predict prognosis. Amyloid burden from 18F-Flutemetamol positron emission tomography (PET), as measured by standardized uptake value ratios (SUVR), might provide prognostic information. Objective: We investigate whether 18F-Flutemetamol PET composite or regional SUVRs are associated with trajectories of clinical progression. Methods: This observational longitudinal study included 94 patients with clinical AD. PET images were semi-quantified with normalization to pons. Group-based trajectory modeling was applied to identify trajectory groups according to change in the Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) over time. Multinomial logistic regression models assessed the association of SUVRs with trajectory group membership. Results: Three trajectory groups were identified. In the regression models, neither composite nor regional SUVRs were associated with trajectory group membership. Conclusion: There were no associations between CDR progression and 18F-Flutemetamol PET-derived composite SUVRs or regional SUVRs in clinical AD.

Positron Emission Tomography Molecular Imaging of the Major Neurodegenerative Disorders: Overview and Pictorial Essay, from a Nuclear Medicine Center's Perspective

“…Three fluorinated types of amyloid radiopharmaceuticals are therefore currently employed for PET/CT and PET/MRI: [ 18 F]Florbetapir, [ 18 F]Flutemetamol (Fig. 8), and [ 18 F]Florbetaben [74,75].…”

Functional Connectivity Change Associated With Apolipoprotein E Allotypes Precedes Structural Connectivity and Neurodegeneration in Cognitive Normal Older Adults Without Cerebral Aβ Deposition

“…We used the standardized uptake value ratio (SUVR) 90 minutes post-injection to analyze 18 F-FMM PET data. 11 SUVRs of the six cortical ROIs (frontal, superior parietal, lateral temporal, striatum, anterior cingulate cortex, and posterior cingulate cortex/precuneus) were averaged to define global cerebral Aβ burden. Consistent with cutoff values used in previous 18 F-FMM PET studies, we initially used neocortical SUVR of 0.62 as the cutoff for amyloid-PET negativity.…”