The fact that CSF p-tau did not differentiate between prodromal AD and AD dementia, while the [18F]AV1451 signal was higher for AD dementia, suggests that p-tau could prove to be a suitable state marker (reflecting disease intensity), while [18F]AV1451 could be useful as a stage marker (reflecting disease progression) [189], given that its binding  is elevated at the prodromal stage with further increases through mild-to-moderate dementia [166]. Here, MAPT is linked to Alzheimer disease.