• Media type: E-Article
  • Title: Neurodegenerative changes in early- and late-onset cognitive impairment with and without brain amyloidosis
  • Contributor: Stage, Eddie C.; Svaldi, Diana; Phillips, Meredith; Canela, Victor Hugo; Duran, Tugce; Goukasian, Naira; Risacher, Shannon L.; Saykin, Andrew J.; Apostolova, Liana G.
  • Published: Springer Science and Business Media LLC, 2020
  • Published in: Alzheimer's Research & Therapy, 12 (2020) 1
  • Language: English
  • DOI: 10.1186/s13195-020-00647-w
  • ISSN: 1758-9193
  • Origination:
  • Footnote:
  • Description: AbstractBackgroundA substantial number of patients clinically diagnosed with Alzheimer’s disease do not harbor amyloid pathology. We analyzed the presence and extent of tau deposition and neurodegeneration in amyloid-positive (AD) and amyloid-negative (nonAD) ADNI subjects while also taking into account age of onset (< or > 65 years) as we expected that the emerging patterns could vary by age and presence or absence of brain amyloidosis.MethodsOne hundred and ten early-onset AD (EOAD), 121 EOnonAD, 364 late-onset AD (LOAD), and 175 LOnonAD mild cognitive impairment (MCI) and dementia (DEM) subjects were compared to 291 ADNI amyloid-negative control subjects using voxel-wise regression in SPM12 with cluster-level family-wise error correction at pFWE < 0.05). A subset of these subjects also received 18F-flortaucipir scans and allowed for analysis of global tau burden.ResultsAs expected, relative to LOAD, EOAD subjects showed more extensive neurodegeneration and tau deposition in AD-relevant regions. EOnonADMCI showed no significant neurodegeneration, while EOnonADDEM showed bilateral medial and lateral temporal, and temporoparietal hypometabolism. LOnonADMCI and LOnonADDEM showed diffuse brain atrophy and a fronto-temporo-parietal hypometabolic pattern. LOnonAD and EOnonAD subjects failed to show significant tau binding.ConclusionsLOnonAD subjects show a fronto-temporal neurodegenerative pattern in the absence of tau binding, which may represent underlying hippocampal sclerosis with TDP-43, also known as limbic-predominant age-related TDP-43 encephalopathy (LATE). The hypometabolic pattern observed in EOnonADDEM seems similar to the one observed in EOADMCI. Further investigation into the underlying etiology of EOnonAD is warranted.
  • Access State: Open Access