CSF sTREM2 and Tau Work Together in Predicting Increased Temporal Lobe Atrophy in Older Adults

Cereb Cortex. 2020 Apr 14;30(4):2295-2306. doi: 10.1093/cercor/bhz240.


Neuroinflammation may be a key factor in brain atrophy in aging and age-related neurodegenerative disease. The objective of this study was to test the association between microglial expression of soluble Triggering Receptor Expressed on Myeloid Cells 2 (sTREM2), as a measure of neuroinflammation, and brain atrophy in cognitively unimpaired older adults. Brain magnetic resonance imagings (MRIs) and cerebrospinal fluid (CSF) sTREM2, total tau (t-tau), phosphorylated181 tau (p-tau), and Aβ42 were analyzed in 115 cognitively unimpaired older adults, classified according to the A/T/(N)-framework. MRIs were repeated after 2 (n = 95) and 4 (n = 62) years. High baseline sTREM2 was associated with accelerated cortical thinning in the temporal cortex of the left hemisphere, as well as bilateral hippocampal atrophy, independently of age, Aβ42, and tau. sTREM2-related atrophy only marginally increased with biomarker positivity across the AD continuum (A-T- #x2292; A+T- #x2292; A+T+) but was significantly stronger in participants with a high level of p-tau (T+). sTREM2-related cortical thinning correlated significantly with areas of high microglial-specific gene expression in the Allen Human Brain Atlas. In conclusion, increased CSF sTREM2 was associated with accelerated cortical and hippocampal atrophy in cognitively unimpaired older participants, particularly in individuals with tau pathology. This suggests a link between neuroinflammation, neurodegeneration, and amyloid-independent tauopathy.

Keywords: Alzheimer’s disease; aging; brain atrophy; neuroinflammation; tau.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Atrophy
  • Biomarkers / cerebrospinal fluid
  • Female
  • Follow-Up Studies
  • Humans
  • Longitudinal Studies
  • Male
  • Membrane Glycoproteins / cerebrospinal fluid*
  • Neurodegenerative Diseases / cerebrospinal fluid*
  • Neurodegenerative Diseases / diagnostic imaging*
  • Neurodegenerative Diseases / psychology
  • Predictive Value of Tests
  • Receptors, Immunologic
  • Temporal Lobe / diagnostic imaging*
  • tau Proteins / cerebrospinal fluid*


  • Biomarkers
  • MAPT protein, human
  • Membrane Glycoproteins
  • Receptors, Immunologic
  • TREM2 protein, human
  • tau Proteins