Linguistic profiles, brain metabolic patterns and rates of amyloid-β biomarker positivity in patients with mixed primary progressive aphasia

Neurobiol Aging. 2020 Dec:96:155-164. doi: 10.1016/j.neurobiolaging.2020.09.004. Epub 2020 Sep 8.

Abstract

We aimed to detail language profiles, brain metabolic patterns and proportion of Alzheimer's disease biomarkers in a cohort of patients with mixed primary progressive aphasia (mPPA). We considered 58 patients with PPA: 10 with non-fluent/agrammatic variant (nfvPPA), 16 with semantic variant (svPPA), 21 with logopenic variant (lvPPA) and 9 with mPPA. Patients with mPPA were further classified as 4 nf/lvPPA (with prevailing features for nfvPPA and lvPPA) and 5 s/lvPPA (with prevailing features for svPPA and lvPPA). Nf/lvPPA patients were characterized by higher proportion of Naming impairment compared to nfvPPA and more frequent Grammatical Errors and Phonologic Errors than lvPPA. S/lvPPA had higher proportion of impairment in Sentences Repetition compared to svPPA and in Single-word Comprehension compared to lvPPA. 100% of nf/lvPPA and 40% of s/lvPPA had Aβ positive biomarkers. Brain hypometabolic pattern in Nf/lvPPA was consistent with lvPPA, while s/lvPPA had a brain metabolism resembling svPPA. We concluded that nf/lvPPA patients might be considered as PPA variant due to Alzheimer's disease and s/lvPPA group mainly included patients with svPPA.

Keywords: Alzheimer's disease; Amyloid biomarkers; Brain metabolism; Frontotemporal dementia; Neuropsychology; Primary progressive aphasia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / diagnosis
  • Alzheimer Disease / metabolism
  • Alzheimer Disease / psychology
  • Amyloid beta-Peptides / metabolism*
  • Aphasia, Primary Progressive / diagnosis
  • Aphasia, Primary Progressive / metabolism*
  • Aphasia, Primary Progressive / psychology*
  • Biomarkers / metabolism
  • Brain / metabolism*
  • Cohort Studies
  • Disease Progression
  • Female
  • Humans
  • Language*
  • Male
  • Middle Aged
  • Speech

Substances

  • Amyloid beta-Peptides
  • Biomarkers