Buckley RF, et al. - Researchers used two cross-sectional cohorts of 296 clinically normal adults to analyze sex differences in the cross-sectional relationship between β-amyloid (Aβ) and regional tau deposition quantified by positron emission tomography (PET). Findings revealed that women with greater amyloid burden exhibited higher entorhinal cortical tau signal vs men with a greater amyloid burden. In amyloid load or apolipoprotein E ε4 frequency no sex differences were found. In women vs men on the trajectory of Alzheimer's disease, early tau deposition was elevated, which supports an increasing body of literature that underscores a biological basis for sex differences in the risk of Alzheimer's disease.