Scientists have found that a simple test of blood platelet activity in middle age may one day become a tool for assessing the risk of Alzheimer’s disease at an early stage—even before the first symptoms appear.

A study conducted by researchers from the Glenn Biggs Institute for Alzheimer's & Neurodegenerative Diseases at the University of Texas San Antonio's Health Science Center, in collaboration with New York University, has revealed a link between the ability of platelets to form clots and early signs of Alzheimer’s disease, detected through positron emission tomography and magnetic resonance imaging (MRI) in middle-aged adults, approximately 56 years old.

The findings were published in the medical journal Neurology.

The researchers analyzed data from 382 participants in the long-term Framingham Heart Study who did not have dementia. Using a test that measures platelet clot formation, the researchers found that individuals with higher levels of platelet aggregation in the blood were more likely to have elevated levels of beta-amyloid and tau proteins in the brain, which are key markers of Alzheimer’s disease.

The study authors note that the strongest link was observed in participants with relatively low baseline platelet activity, while the effect was less pronounced in those with higher activity.

According to the researchers, platelets may serve as a “bridge” between vascular disorders—deterioration of blood vessels in the brain—and the neurodegenerative processes that lead to the development of Alzheimer’s disease.

Scientists emphasize that this test is not yet widely applicable in practice, and further clinical studies are needed to determine whether the observed pattern persists over time.

However, the findings already offer hope that in the future, a simple blood test may emerge that can determine the risk of the disease long before its clinical manifestation.