GFAP and frontotemporal dementia: Plasma GFAP levels were normal in those with FTD despite gliosis being a characteristic of FTD.38,39 Second, in ALFA+, the A–T+ group did not have high plasma GFAP levels; this finding may suggest that plasma GFAP levels specifically reflect Aβ pathology in preclinical stages, but a direct comparison with the preclinical stage of other neurodegenerative diseases should be performed.