FRIDAY, Nov. 6, 2026 (HealthDay News) -- Patients with early-onset Alzheimer disease (EOAD) have more extensive deposits of tau compared with those with late-onset Alzheimer disease (LOAD), according to a study published online Nov. 4 in Science Translational Medicine.Konstantinos Chiotis, M.D., Ph.D., from the Weill Institute for Neurosciences at the University of California, San Francisco, and colleagues compared baseline and longitudinal tau positron emission tomography (PET) burden measured with 18F-flortaucipir and its relationship with clinical variables in amyloid PET-positive, cognitively impaired participants from the Longitudinal Early-Onset Alzheimer's Disease Study (390 participants with EOAD) and Alzheimer's Disease Neuroimaging Initiative (211 participants with LOAD).The researchers found higher baseline tau PET burden, broader neuroanatomical involvement, stronger association of tau PET with amyloid PET, and cognitive burden in EOAD. In participants with EOAD from the Alzheimer's Disease Neuroimaging Initiative, the higher baseline tau PET burden in EOAD was independently validated. Independent of amyloid PET and clinical stage, longitudinally, tau PET increased more rapidly in EOAD than LOAD."We found that tau accumulation and spread was particularly aggressive in patients with early-onset disease and was more strongly related to progression in memory loss," senior author Gil D. Rabinovici, M.D., also from the Weill Institute for Neurosciences, said in a statement.Several authors disclosed ties to the biopharmaceutical and medical technology industries.Abstract/Full Text (subscription or payment may be required).Sign up for our weekly HealthDay newsletter