GFAP and Alzheimer disease: This suggests that elevated blood GFAP levels are associated with amyloid burden in Alzheimer’s disease, consistent with findings from other studies.9,19 Furthermore, GFAP levels also correlated with brain amyloid loading and disease severity, with significantly higher plasma GFAP in AD-Aβ+ compared with MCI Aβ+ (P < 0.001) and CU Aβ+ (P < 0.01) as well as between MCI Aβ+ against AD-Aβ+ (P < 0.001).