A smaller proportion of downregulated proteins, 6 out of 22 proteins (CHGA, SCG5, BCAN, CTTN, TNR, and SPOCK2), appeared as modified in AD CSF in previous studies (Bastos et al., 2017; Higginbotham et al., 2020; Pedrero‐Prieto et al., 2020; Visser et al., 2022; Wesenhagen et al., 2020). Here, BCAN is linked to Alzheimer disease.