According to a recent study published in the journal Nature Medicine, scientists have developed a blood test that, in addition to determining the risk of disease development, functions as a molecular “clock.” It can predict exactly when a patient will begin to experience memory loss and other clinical symptoms.
Researchers analyzed data from 600 elderly individuals, focusing on a specific form of the tau protein — p-tau217. It was discovered that the ratio between this protein and its normal form in the blood begins to rise long before cognitive symptoms appear.
The most significant finding is the consistency of this process: the rate of p-tau217 increase proved to be so similar across different individuals that scientists were able to create a mathematical model. By factoring in age and blood data, the test can determine with 3-4 years of accuracy when a critical threshold will be crossed and the visible phase of the disease will begin.
Previously, predicting the disease at an early stage was only possible through expensive and complex imaging methods, such as PET scans; however, this new blood test significantly simplifies the process. The technology allows doctors to intervene before irreversible damage to nerve cells begins.
Despite these promising results, specialists urge caution. At this stage, they do not recommend that healthy individuals undergo the test independently. Given the current lack of effective and safe treatments, the practical application of this molecular “clock” will only become fully relevant once medicine possesses the corresponding therapeutic tools.
