Medial temporal lobe atrophy patterns in early-versus late-onset amnestic Alzheimer’s disease
Anika Wuestefeld, Alexa Pichet Binette, Danielle van Westen, Olof Strandberg, Erik Stomrud, Niklas Mattsson, Shorena Janelidze, Ruben Smith, Sebastian Palmqvist, Hannah Baumeister, David Berron, Paul A. Yushkevich, Oskar Hansson, Nicola Spotorno, Laura E.M. Wisse
Abstract
BACKGROUND: The medial temporal lobe (MTL) is hypothesized to be relatively spared in early-onset Alzheimer's disease (EOAD). Yet, detailed examination of MTL subfields and drivers of atrophy in amnestic EOAD is lacking. METHODS: BioFINDER-2 participants with memory impairment, abnormal amyloid-β and tau-PET were included. Forty-one amnestic EOAD individuals ≤65 years and, as comparison, late-onset AD (aLOAD, ≥70 years, n = 154) and amyloid-β-negative cognitively unimpaired controls were included. MTL subregions and biomarkers of (co-)pathologies were measured. RESULTS: AD groups showed smaller MTL subregions compared to controls. Atrophy patterns were similar across AD groups: aLOAD showed thinner entorhinal cortices than aEOAD; aEOAD showed thinner parietal regions than aLOAD. aEOAD showed lower white matter hyperintensities than aLOAD. No differences in MTL tau-PET or transactive response DNA binding protein 43-proxy positivity were found. CONCLUSIONS: We found evidence for MTL atrophy in amnestic EOAD and overall similar levels to aLOAD of MTL tau pathology and co-pathologies.