A blood test would detect Alzheimer’s 20 years before memory loss
A blood test developed by US researchers would detect the presence of Alzheimer’s disease until 20 years before the appearance of the first memory loss.
This new test may even be even more accurate than positron emission tomography (PET scan), which is normally used to confirm the presence of amyloid deposits in the brain.
These deposits begin to engulf the brain for up to two decades before the memory loss and confusion typical of Alzheimer’s disease occur.
The test developed by researchers at Washington University, Saint-Louis, measures amyloid levels in the blood. When these levels are combined with the age of the patient and the presence of a genetic variant called APOE4, the test detects the presence of amyloid deposits in the brain with an accuracy of 94 percent.
The risk of suffering from the disease doubles every five years from the age of 65. The APOE4 genetic variant increases this risk by three to five times.
The test is so precise that it was sometimes able to detect the presence of deposits a few years before positron emission tomography was able to do so.
The clinical impact of the test could be monumental, since it could identify very early patients in whom amyloid deposits have begun to form to test treatments for them to slow down or stop the progression of the disease. . Currently, patients are treated only after the onset of symptoms, when their brains are already severely damaged.
The findings of this study are published by the medical journal Neurology.