A simple blood test to detect Alzheimer’s disease soon?

Soon, a simple blood test may be enough. Scientists at the University of Gothenburg in Sweden have experimented with a blood test aimed at detecting Alzheimer’s disease. The results of their study were published this week in the American Journal JAMA NeurologyAnd they are promising.

Less painful and invasive, but also less expensive than reference tests, this test may soon “revolutionize” the diagnosis of the disease, experts are already happy. How does this test work? And what therapeutic advances could this lead to? 20 minutes explains you.

Protein discovery

As part of this study, conducted on 786 people with or without cognitive disorders, the researchers used the “ALZpath p-tau217” test to determine three groups among the participants: probable, moderate probable and unlikely to suffer from cognitive disorders. Alzheimer’s disease. For this, the test “phosphorylated tau protein (p-tau217), which is a specific blood biomarker of Alzheimer’s disease,” explain the authors of the study.

Previous work on the same protein showed that it could be used to differentiate Alzheimer’s disease from other neurodegenerative disorders and help detect the disease even in cases of mild cognitive impairment. Problem: Availability of these tests for research and clinical use is limited. The researchers therefore aimed to “determine the utility of the new commercially available ALZpath blood test for detecting Alzheimer’s disease”.

A promising option

If this study arouses much excitement, it is because researchers have discovered that this blood test offers a very high level of precision, opening up a promising alternative to the reference tests used to diagnose the disease. “These results show that a blood test can accurately detect the presence of proteins that accumulate in the brain and cause Alzheimer’s disease,” commented Charles Marshall, professor of clinical neurology at Queen Mary University. from London, Science Media Center. In current practice, the only way to prove that a person has an accumulation of this protein in the brain is with a lumbar puncture or a PET scan (amyloid brain scan), which is only available at a clinic. Memory in the United Kingdom in the twenties.

In the first instance, very painful examinations for patients, including “examination of cerebrospinal fluid taken by lumbar puncture, in search of biological markers of disease,” recalls the health insurer. And very expensive, therefore less easily accessible, for another, which makes it possible to “highlight the decrease in the functioning of the affected brain areas”.

But in the future, “80% of individuals could be diagnosed on the basis of a blood test without further investigation,” Dr Ashton assured. The co-author of the study continued that “to get (the latest treatment that slows cognitive decline), you have to prove that you have amyloid in your brain” is even more interesting since then. However, it is impossible to perform lumbar punctures and brain scans on everyone in the world who needs them. This is where the blood test () has huge potential.”

Previous treatment of the disease

Another benefit of this blood test: It can allow early detection and treatment of disease. “This study is a very welcome step forward, as it shows that blood tests can be just as accurate as more invasive and expensive tests to predict whether a person has symptoms of Alzheimer’s disease in the brain,” research director Dr. Richard Oakley expressed his delight. and innovation at the Alzheimer Society Science Media Center.

British Association Alzheimer Research Director of Research Dr. An enthusiasm shared by Shiona Scales, who reminds the same media that “people with dementia often face unacceptable delays in getting a diagnosis, and with new treatments on the horizon, that’s never been the case. How are people with possible symptoms of Alzheimer’s disease diagnosed?” It is more important to make a change.” However, notes Dr. Oakley, “we need to do more research in different communities to understand the effectiveness of these blood tests in all people living with Alzheimer’s disease.” But “if these results are reproduced in real clinical contexts, phosphorylated tau protein (p-tau217) has the potential to revolutionize the diagnosis of Alzheimer’s disease,” predicts Jonathan M. Scott, professor of neurology at the Center for Dementia Research UK.

In France, “almost one million people will be affected by Alzheimer’s”, or “8% of French people over 65 will be affected in 2020”, according to the Vancry Alzheimer Foundation, which “estimates that 225,000 new cases are diagnosed each year.” In France .

Anissa Boumedienne