Table 1. Staging categories for preclinical AD research.
Stage | Description | Aβ (PET or CSF) | Markers of neuronal injury (tau, FDG, sMRI) | Evidence of subtle cognitive change |
---|---|---|---|---|
Stage 1 | Asymptomatic cerebral amyloidosis | Positive | Negative | Negative |
Stage 2 | Asymptomatic amyloidosis + “downstream” neurodegeneration | Positive | Positive | Negative |
Stage 3 | Amyloidosis + neuronal injury + subtle cognitive/behavioral decline | Positive | Positive | Positive |
Abbreviations: AD, Alzheimer's disease; Aβ, amyloid beta; PET, positron emission tomography; CSF, cerebrospinal fluid; FDG, fluorodeoxyglucose (18F); sMRI, structural magnetic resonance imaging.