Blood test measuring p-tau217 predicts Alzheimer's risk up to ten years in advance

A blood test that detects the protein p-tau217 may allow clinicians to estimate the risk of Alzheimer's disease a decade before symptoms appear, researchers said. The study, presented at the Alzheimer's Association International Conference in London and published in the Journal of the American Medical Association, followed nearly 2,700 cognitively healthy participants with an average age of 70 for up to ten years. Participants with the highest p-tau217 concentrations had an estimated 78% chance of developing cognitive impairment within ten years and about a one-in-three chance within five years, while those with moderately elevated levels faced a 45% ten-year risk. > "Once verified, these blood tests could be used to recruit patients for clinical trials of treatments to prevent cognitive decline and dementia," said Rachel Buckley, lead author and associate professor of neurology at Harvard Medical School. > "In the future, when treatments are approved for use early in the disease process, these tests could help guide monitoring, treatment decisions and counseling for patients and families," she added. The researchers noted that p-tau217 alone does not determine an individual's outcome; factors such as age, genetics, kidney function and racial background also affect risk. They called for longer studies in more diverse populations to refine risk estimates. > Maria Carrillo, chief science officer of the Alzheimer’s Association, said early identification of at-risk individuals could change how the disease is diagnosed, treated and potentially prevented.