The Successful Aging after Elective Surgery Study examined the association of the levels of plasma NfL, total tau, glial fibrillary acid protein, and ubiquitin carboxyl-terminal hydrolase L1 with delirium, delirium severity, and cognitive performance in older adults without dementia who are undergoing major elective surgery (Fong et al., 2020). This evidence concerns the gene MAPT and delirium.