Serum NFL remained significantly associated with the presence of delirium (compared to non-AD controls and AD combined) in a multiple regression, adjusting for the influence of age, cortical atrophy, cerebral microangiopathy, and previously diagnosed dementia (βdelirium = 0.8087, pdelirium = 0.0004, βage = 0.0080, page = 0.4230, βatrophy = 0.4943, patrophy = 0.0088, βmicroangiopathy = −0.2661, pmicroangiopathy = 0.1858, βdementia = −0.2334, pdementia = 0.3542, R2 = 0.2645; Supplementary Table 2). Here, NEFL is linked to dementia.