A team of scientists has created a new blood test that can do more than just detect Alzheimer’s disease. It can also show how far the disease has progressed in a person’s brain. This test could help doctors decide what kind of treatment might work best for each patient.
The study was done by researchers at Washington University in St. Louis and Lund University in Sweden, and the results were published in the journal Nature Medicine.
Alzheimer’s disease is a condition that slowly damages the brain. It causes memory loss, confusion, and problems with thinking and daily activities. The disease develops over many years. In the early stages, a protein called amyloid starts to build up in the brain, forming sticky plaques.
Later, another protein called tau forms twisted clumps, known as tangles. These tau tangles are strongly linked to the symptoms of Alzheimer’s, such as memory problems.
Until now, the only accurate way to measure these changes in the brain was by doing a special kind of scan called a PET scan. But PET scans are expensive, time-consuming, and not available in most hospitals. They are usually only found in large research centers.
Blood tests for Alzheimer’s already exist, including two based on technology from Washington University. These tests help doctors find out whether a person with memory problems has Alzheimer’s, but they don’t show how far the disease has gone.
That’s important because Alzheimer’s drugs work best in the early stages. If doctors could easily see how advanced the disease is, they could choose better treatments for each person.
The new test focuses on a specific form of the tau protein, called MTBR-tau243. Researchers found that the amount of MTBR-tau243 in the blood closely matches the amount of tau tangles in the brain. In other words, the higher the level in the blood, the worse the disease in the brain.
To develop the test, the researchers first studied spinal fluid samples, which are harder to collect because they require a needle in the back. Then, they found a way to measure MTBR-tau243 in regular blood samples. They tested blood from volunteers in the U.S. and Sweden. Some had no memory problems, while others had mild or severe symptoms.
The results were impressive. The blood test correctly showed how much tau was in the brain with 92% accuracy. People in the early stages of Alzheimer’s had higher levels of MTBR-tau243 than healthy people, and those in the later stages had even higher levels—sometimes up to 200 times more.
People with memory problems caused by other diseases had normal MTBR-tau243 levels, so the test also helped rule out Alzheimer’s in those cases.
This means the test could not only tell if someone has Alzheimer’s, but also how far along the disease has gone. That’s a big step forward in helping doctors give the right treatment at the right time.
The technology is being developed by a company called C2N Diagnostics, which also made earlier blood tests for Alzheimer’s. One of the existing tests looks for another form of tau called p-tau217, which is good for detecting if someone has Alzheimer’s. But MTBR-tau243 gives more information about how serious the condition is.
Researchers say using both tests together will help doctors get a clearer picture of each patient’s situation. This can help doctors choose whether to start with anti-amyloid drugs in the early stages or try new experimental treatments that work better in the later stages.
Right now, only two drugs are approved in the U.S. to slow Alzheimer’s, and they target amyloid. But more treatments are being tested, including ones that target tau and other changes in the brain.
With more drug options and these new blood tests, doctors may soon be able to create personalized treatment plans based on what stage of Alzheimer’s a person is in.
Review and Analysis of the Findings
This study marks a major step toward personalized care for Alzheimer’s disease. The new blood test makes it possible to detect the presence and severity of the disease without costly scans. It offers a less invasive and more accessible tool for doctors and could be especially helpful in areas where brain imaging isn’t available.
The key strength of this blood test is its ability to reflect how much tau is in the brain—a strong indicator of how far Alzheimer’s has progressed. The fact that it can also separate Alzheimer’s from other types of dementia makes it a powerful diagnostic tool.
If approved for clinical use, this test could help millions of patients by ensuring they get the right treatment at the right time. It could also speed up research by helping scientists identify the best candidates for clinical trials.
Overall, this is a promising advancement that brings us closer to earlier, easier, and more personalized treatment for Alzheimer’s disease.
If you care about brain health, please read studies about vitamin D deficiency linked to Alzheimer’s and vascular dementia, and blood pressure problem at night may increase Alzheimer’s risk.
For more information about brain health, please see recent studies about antioxidants that could help reduce dementia risk, and epilepsy drug may help treat Alzheimer’s disease.
The research findings can be found in Nature Medicine.
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