Translational Psychiatry (Jan 2021)

Mild behavioral impairment and its relation to tau pathology in preclinical Alzheimer’s disease

  • Maurits Johansson,
  • Erik Stomrud,
  • Philip S. Insel,
  • Antoine Leuzy,
  • Per Mårten Johansson,
  • Ruben Smith,
  • Zahinoor Ismail,
  • Shorena Janelidze,
  • Sebastian Palmqvist,
  • Danielle van Westen,
  • Niklas Mattsson-Carlgren,
  • Oskar Hansson

DOI
https://doi.org/10.1038/s41398-021-01206-z
Journal volume & issue
Vol. 11, no. 1
pp. 1 – 8

Abstract

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Abstract Mild behavioral impairment (MBI) is suggested as risk marker for neurodegenerative diseases, such as Alzheimer’s disease (AD). Recently, pathologic tau deposition in the brain has been shown closely related to clinical manifestations, such as cognitive deficits. Yet, associations between tau pathology and MBI have rarely been investigated. It is further debated if MBI precedes cognitive deficits in AD. Here, we explored potential mechanisms by which MBI is related to AD, this by studying associations between MBI and tau in preclinical AD. In all, 50 amyloid-β-positive cognitively unimpaired subjects (part of the BioFINDER-2 study) underwent MBI-checklist (MBI-C) to assess MBI, and the Alzheimer’s Disease Assessment Scale – Cognitive subscale (ADAS-Cog) delayed word recall (ADAS-DR) to assess episodic memory. Early tau pathology was determined using tau-PET ([18F]RO948 retention in entorhinal cortex/hippocampus) and cerebrospinal fluid (CSF) P-tau181. Regression models were used to test for associations. We found that higher tau-PET signal in the entorhinal cortex/hippocampus and CSF P-tau181 levels were associated with higher MBI-C scores (β = 0.010, SE = 0.003, p = 0.003 and β = 1.263, SE = 0.446, p = 0.007, respectively). When MBI-C and ADAS-DR were entered together in the regression models, tau-PET (β = 0.009, p = 0.009) and CSF P-tau181 (β = 0.408, p = 0.006) were predicted by MBI-C, but not ADAS-DR. We conclude that in preclinical AD, MBI is associated with tau independently from memory deficits. This denotes MBI as an important early clinical manifestation related to tau pathology in AD.