TABLE 2.

Comparison of staging categories for pre‐clinical AD between the NIA‐AA (A) and AD overture (B) guidelines

(A)
Stage	Description	Aβ‐PET, low CSF Aβ1–42	High CSF tau/P‐tau, neuronal dysfunction (FDG‐PET or fMRI), cortical thinning, hippocampal atrophy (sMRI)	Subtle cognitive decline
1	Asymptomatic cerebral amyloidosis	Positive	Negative	Negative
2	Asymptomatic cerebral amyloidosis +“downstream” neurodegeneration	Positive	Positive	Negative
3	Cerebral amyloidosis +Neurodegeneration +Subtle cognitive decline	Positive	Positive	Positive

(B)
Stage	Description	Tau‐PET	Aβ‐PET, low CSF Aβ1–42	High CSF tau/P‐tau, neuronal dysfunction (FDG‐PET or fMRI), hippocampal atrophy (sMRI)	Subtle cognitive decline
1	Asymptomatic primary tauopathy	Positive	Negative	Negative	Negative
2	+Asymptomatic cerebral amyloidosis	Positive	Positive	Negative	Negative
3	+Positive CSF tau biomarkers, +cerebral dysfunction	Positive	Positive	Positive	Negative
4	+subtle cognitive decline	Positive	Positive	Positive	Positive

Abbreviations: Aβ, β‐amyloid; FDG, fluorodeoxyglucose (18F); fMRI, functional magnetic resonance imaging; PET, positron emission tomography; sMRI, structural MRI.