NEFL and Alzheimer disease: According to the AT(N) categorization in the revised criteria for the diagnosis and staging of AD,4 18F‐florbetapir (AV45) PET was used to evaluate Aβ deposition, plasma phosphorylated tau (p‐tau)181 levels were measured to assess tau pathology, and N was characterized by decreased hippocampal volume (HV) on anatomical MRI, reduced brain metabolism on FDG PET, and elevated plasma NfL levels.