Alzheimer's & Dementia · Sep 8, 2021

Relationships among tau burden, atrophy, age, and naming in the aphasic variant of Alzheimer's disease

By Martersteck A, Sridhar J, Coventry C et al.

INTRODUCTION: Examination of pathologic, anatomic, and cognitive relationships has been limited in primary progressive aphasia (PPA) with underlying Alzheimer's disease (AD) neuropathology. METHODS: Spatial relationships between tau positron emission tomography (PET), cortical thickness, age, and naming on the Boston Naming Test (BNT) in PPA with biomarker evidence of AD (PPA-AD) were examined. RESULTS: Higher tau PET burden was associated with atrophy and younger age. There was a significant left-lateralized relationship between lower BNT and more atrophy, and between lower BNT and increased tau burden. Variance in naming was primarily shared between tau and atrophy (51%), but naming was uniquely explained more by atrophy (32%) than tau (16%). Higher left anterior temporal tau burden was associated with greater 1-year rate of decline in naming. DISCUSSION: PPA-AD has a similar relationship between abnormal biomarkers as first described in amnestic AD, with differing spatial extent, reflecting the left-lateralized nature of the language network.

doi.org/10.1002/alz.12445 Open access, accepted manuscript PubMed 34494711 Mechanisms