MAPT and Alzheimer disease: Alzheimer's disease (AD) has been reported to be present at higher rates after TBI,12 yet this specific relationship has only been substantiated with neuropathology confirmation in a limited number of cases13 and not consistently so.14 Notably, acute severe TBI has been associated with widespread amyloid plaque pathology,15 but this should be considered distinct from ‘AD pathology’ per se [i.e. amyloid-β (Aβ) plaque and paired helical filament tau tangle pathology].