GFAP and Alzheimer disease: Similarly, all ND groups showed higher levels of GFAP than controls (prion disease vs. controls p = 0.002, FTD vs. controls p = 0.004, AD vs. controls p = 0.029), with no significant differences among the disease groups (Table 2, Fig. 1d), even after age and sex adjustment (Additional file 1: Table S3).