Blood Test Predicts Alzheimer’s Risk Years in Advance

Recent research indicates that a particular blood test could forecast the risk and timing of Alzheimer’s symptoms, even a decade or two ahead of their onset.

According to a study published in the medical journal JAMA Network Open, a straightforward blood test appears capable of accurately identifying whether someone is likely to develop Alzheimer’s symptoms 10 to 20 years before those symptoms actually appear.

Alzheimer’s disease, a progressive disorder that gradually diminishes memory and cognitive abilities, currently impacts about 7.4 million Americans, as noted by the Alzheimer’s Association. This new blood test examines levels of a biomarker called p-tau217.

The report details how researchers gathered data from over 2,600 cognitively healthy older adults. These individuals underwent blood tests, brain scans, and cognitive evaluations at Mass General Brigham Neuroscience Institute in Boston.

Results showed that those with significantly elevated levels of this biomarker have about a 38% chance of developing cognitive impairment within five years, and that risk grows to 78% within a decade.

While the blood test has received federal approval, the study mentions it’s too early to recommend it for asymptomatic individuals.

Dr. Reisa Sperling, the study’s senior author, emphasized, “Wait and get tested when you can potentially do something about it. At this point, it wouldn’t change what I would tell someone to do. I’d still advise them to eat well, get enough sleep, exercise regularly, and stay engaged.”

However, Sperling noted that the test could soon be accessible due to advancements in clinical trials for new therapies.

She explained, “This is a gradual process where amyloid and tau accumulate in the brain, and this biomarker indicates how far along someone is in that process.”

Lead author Dr. Rachel Buckley, a cognitive neuroscientist at Mass General, added, “This research is a crucial step in understanding what p-tau217 can reveal about an individual’s risk for cognitive impairment. What makes this study unique is its ability to assess a person’s risk level.”

To further validate and enhance these findings, future studies will be necessary to monitor a more diverse range of populations over extended periods.

The research findings were published in JAMA and shared at the Alzheimer’s Association International Conference in London.