Turn on cookies to sign in
Signing in saves your progress to your Curie account. We can only do that with cookies on — turn them on to continue.
A simple blood test could flag Alzheimer's risk years before memory problems begin. A large international study found that people with the highest levels of a brain protein called p-tau217 had a 38% chance of cognitive decline within five years — rising to 78% by 10 years. Researchers say this could eventually reshape early Alzheimer's prevention, much like cholesterol tests guide heart disease care.
A major international study has found that a blood test measuring a protein called phosphorylated tau 217 (p-tau217) can predict Alzheimer's-related cognitive decline up to a decade before any symptoms appear. Led by scientists at the Mass General Brigham Neuroscience Institute and published in JAMA, the study pooled data from 2,684 cognitively healthy older adults across six studies in North America, Japan, and Australia — making it one of the most comprehensive analyses of its kind.
The results were striking: among those with the highest p-tau217 levels, the estimated risk of developing cognitive impairment hit 38% within five years and 78% within 10 years. Crucially, the biomarker predicted decline even beyond what brain scans and genetic risk factors (like APOE4) could explain on their own.
Key Takeaways:
Why it matters: If prevention trials succeed, p-tau217 testing could identify who benefits most from early treatment — transforming Alzheimer's care from reactive to preventive.
