GFAP and Alzheimer disease: The latter can be either specific to AD (e.g., phosphorylated tau 181 [p-tau181] and 42-aminoacid β amyloid peptide [Aβ-42]) or non-specific (e.g., total tau [t-tau], neurofilament light [NfL], and glial fibrillary acidic protein [GFAP]), have been shown to correlate with CSF and cerebral positron emission tomography (PET) biomarkers of AD pathology, and may be used to predict both all-cause dementia and AD-specific dementia [16,17].