MAPT and dementia: Compared with controls, CSF p-tau increases were steeper in the amyloid-positive cognitively unimpaired (P = .04) and amyloid-positive MCI (P = .003) groups, while CSF t-tau increases were steeper in the amyloid-positive MCI (P < .001) and the amyloid-positive dementia groups (P = .046) compared with controls.