GFAP levels were significantly higher in the MCI group than in the CN group after adjusting for potential risk factors (Li et al., 2020; Marizzoni et al., 2023) for AD such as age, gender, education, and APOE ε4 allele carrier status (F = 4.71, P = 0.038) (Figure 1A). Here, GFAP is linked to Alzheimer disease.