Fig. 1

Plasma NTA-tau levels across clinical diagnosis and disease stages. Plasma NTA-tau levels in BioFINDER-2 by clinical diagnosis (A), A/T status (B) and Braak stages (C). Plasma NTA-tau levels in BioFINDER-1 by clinical diagnosis (D). Differences of plasma levels by diagnostic groups were measured using ANCOVA and Tukey’s method for post-hoc comparisons. Age and sex were used as covariates in all cases. Aβ (A) status was assessed using CSF Aβ42/40 levels and tau (T) status using tau-PET SUVR based on previously validated cut-offs. Participants with available tau-PET imaging were stratified according to the PET Braak stages in a hierarchical manner, based on regional SUVR cut-offs. In D we divided the y-axis to show few cases with very high plasma NTA-tau levels. *: p < 0.05; **: p < 0.01; ***: p < 0.001. Box plots include all participants, displaying the median and the interquartile range; whiskers show the lower value of maximum/minimum value or 1.5 interquartile range from the hinge. Abbreviations: Aβ, amyloid-β; AD+ , Alzheimer’s dementia Aβ-positive; A-T-, Aβ and tau negative; A+T-, Aβ-positive tau negative; A+T+ , Aβ and tau positive; A-T+ , Aβ-negative tau positive; CSF, cerebrospinal fluid; CU-, cognitively unimpaired Aβ-negative; CU+ , cognitively unimpaired Aβ-positive; MCI+ , mild cognitive impairment Aβ-positive nonAD+ ; non-Alzheimer’s type dementia Aβ-positive; non-AD-, non-Alzheimer’s type dementia Aβ-negative; SUVR, standardized uptake value ratio