Study from CTAD 2023 Compares Sensitivity of 4 Blood-Based Biomarkers for Preclinical Alzheimer Disease

A study comparing the sensitivity of amyloid beta (Aβ) 40/42 ratio, plasma phosphorylated tau at threonine 181 (p-tau181), p-tau217, and neurofilament light chain (NfL) in low-risk (LR) versus high-risk (HR) cognitively healthy adults found that p-tau217 was associated with both high-risk for developing Alzheimer disease (AD) and elevated neocortical amyloidosis. These results were presented at the 16th annual Clinical Trials on Alzheimer’s Disease (CTAD) conference.

All participants (N=98, aged 55-80 years) were without cognitive impairments and had mean Montreal Cognitive Assessment (MoCA) general cognition scores of 27 (SD, 1.7). LR participants (n=43) were APOE ε4 negative, had no family histories for AD, and no subjective memory impairment (SMI), whereas HR subjects (n=55) carried at least 1 apolipoprotein E ε4 (APOE ε4) allele, had a family history for AD, and SMI. The only difference between LR and HR participants was observed for p-tau217 (HR > LR, P=.03). Furthermore, in a subgroup of 25 participants who received a Florbetapen amyloid PET scan, differences in elevated versus non-elevated neocortical amyloidosis were observed for the Aβ 40/42 ratio (HR < LR, P=.03) and p-tau217 (HR > LR, P=.00005), with a greater between-group difference for p-tau217 (AUC=0.850).

This study was supported by the Morton Plant Mease Health Care Foundation and includes researchers affiliated with ALZPath, The University of Rhode Island, and Brown University.