Figure 2.

Plasma and CSF GFAP concentrations are associated with amyloid-β-PET independently of tau-PET burden. Results of the linear regression analyses showing a significant relationship between amyloid-β burden measured on PET (Aβ-PET) (z-scores) and plasma GFAP (z-scores) in (A) all cognitively unimpaired individuals (CU), (B) amyloid-β-negative cognitively unimpaired individuals (CU Aβ−), (C) amyloid-β-positive cognitively unimpaired individuals (CU Aβ+), and (D) amyloid-β-positive cognitively impaired individuals (CI Aβ+), after adjusting for age and sex. In addition, a significant relationship between amyloid-β-PET and CSF GFAP (z-scores) was also found in (E) amyloid-β-positive cognitively unimpaired individuals (CU Aβ+). The top panel shows correlation plots between amyloid-β-PET and GFAP markers, whereas the bottom panel shows box plots depicting how amyloid-β-PET values vary according to GFAP quartiles. All associations remained significant after controlling for tau-PET burden.