A p-tau217 blood test predicted a 78% chance of cognitive decline within 10 years for symptom-free adults with very high levels of the biomarker.
https://www.foxnews.com/health/new-alzheimers-blood-test-predicts-develop-dementia-5-10-years
https://www.foxnews.com/health/new-alzheimers-blood-test-predicts-develop-dementia-5-10-years