As indicated in Table 1, there was a significant rise in plasma levels of GFAP, p‐tau217, NfL, apolipoprotein E (APOE) ε4 prevalence, AV45‐PET positivity, and global AV45‐SUVR from the CN group to the MCI group and then to the dementia group, while hippocampal volumes significantly decreased. This evidence concerns the gene APOE and dementia.