GFAP and Alzheimer disease: The combination of GFAP with the age+sex+APOE4 panel (age+sex+APOE4+GFAP panel) obtained an AUC of 91.3% (95%CI = 0.85–0.97) for HC vs. AD (p < 0.001, Figure 3A) and AUC of 81.3% (95% CI = 0.72–0.90) for HC vs. MCI (p < 0.01, Figure 3B) compared to the age+sex+APOE4 panel.