Exploring healthy aging through preclinical Alzheimer disease in the Knight Alzheimer Research Imaging dataset

Alzheimer disease (AD) remains a significant global public health challenge, requiring robust multimodal datasets to elucidate its prolonged preclinical phase, improve early detection, advance understanding of disease trajectories, and guide intervention strategies. Here we present the Knight Alzheimer Research Imaging (KARI) dataset, established by the Washington University Knight ADRC to address this critical need. We detail comprehensive multimodal neuroimaging from 1,645 participants (aged 42-97) across 6,217 acquisitions. Spanning the AD spectrum from healthy aging to symptomatic disease, the cohort undergoes extensive longitudinal imaging using structural and functional magnetic resonance imaging (MRI) alongside positron emission tomography (PET) tracers for amyloid and tau pathology. This is complemented by rich clinical, cognitive, genetic, and biomarker data. In addition to raw imaging, the dataset provides quality-controlled processed outputs, including anatomical segmentations and biomarker quantification. By making this data accessible to researchers, the Knight ADRC aims to accelerate discoveries in pathophysiology, biomarker identification, and therapeutic development. The KARI dataset maps healthy aging through preclinical Alzheimer disease across >6,000 scans from 1,645 adults. Demonstrating its utility, imaging biomarkers scale with clinical severity, providing a resource to accelerate future Alzheimer research.