GFAP and Alzheimer disease: Only plasma p-tau217 was included in this study, given the similarity in performance to other phosphorylated isoforms, such as p-tau181,29 but isoforms like p-tau231 may have different utility for the milder range of the AD spectrum.53 Additionally, inclusion of other plasma biomarkers, such as Aβ ratios,28 neurofilament light chain,32 and glial fibrillary acidic protein,54 may have roles in prognostic stratification or as exploratory outcomes in clinical trials, and future studies should explore the added value of these biomarkers.