Cohort characteristics
We performed cross-sectional and longitudinal analyses in four independent cohorts. Cohort-1 was the Dementia Disease Initiation (DDI, Norwegian national multicenter study) cohort (n = 364) which longitudinally follows older adults who were CN (n = 221) or had early MCI (n = 143) at study entrance. Cross-sectional analyses in this cohort allowed us to investigate associations of plasma (and CSF) BD-tau with CSF t-tau and Aβ42/β40 ratio, the soluble neurodegeneration and Aβ pathophysiology markers included in the AT(N) framework2, as well as longitudinal cognition and MRI-derived neurodegeneration evaluations. Of the included participants, n = 255 had repeated cognitive measurements up to 8.25 years (mean = 3.22, SD = 1.56 years). A total of n = 269 participants also had MRI scans; n = 136 had repeated MRIs up to 7.66 years (mean =…
