MAPT and early-onset autosomal dominant Alzheimer disease: To systematically investigate tau-PET as a single predictive marker for future cognitive decline, we included 396 subjects from the Alzheimer’s disease neuroimaging initiative (ADNI) ranging from cognitively normal to AD dementia, characterized by baseline 18F-Florbetapir/18F-Florbetaben amyloid-PET, 18F-Flortaucipir tau-PET, and ~ 2-year follow-up assessments of global cognitive and memory performance.