Scientists are seeking to develop a blood test that could early diagnose Alzheimer’s disease, without the need for expensive brain imaging or a painful puncture in the back to withdraw a sample of cerebrospinal fluid, according to the newspaper.Guardian” British.
The research team hopes that the new method, after its adoption, will allow a faster diagnosis of the disease, and thus start treatment at an early date.
Alzheimer’s is the most common form of dementia, but its diagnosis remains difficult, especially during the early stages of the disease.
The current guidelines recommend detecting three diagnostic markers of the disease, which are abnormal accumulations of amyloid and tau proteins, as well as monitoring for neurodegeneration, which means the slow and gradual loss of neurons in specific regions of the brain.
These signs can be detected through a combination of brain imaging and cerebrospinal fluid analysis.
However, a lumbar puncture (inserting a needle into the space between two lumbar vertebrae to take a sample of cerebrospinal fluid) can be painful, and people may experience headaches or back pain after the procedure, while brain scans are very expensive and take a long time to make an appointment until in many developed countries.
“Many patients, even in the United States, do not have access to MRI machines and PET scans,” explained Professor Thomas Karikare, from the University of Pittsburgh in Pennsylvania, US, who participated in the study published in the journal Brain. .
He noted that developing a reliable blood test is an important step forward, adding: “Such a test would be cheaper and safer, and could improve clinical confidence in diagnosing Alzheimer’s disease.”
Although current blood tests can accurately detect abnormalities in the amyloid and tau proteins, detecting signs of damage to neurons specific to the brain has been much more difficult.
Worldwide, Karikari and his colleagues focused on developing an antibody-based blood test that would detect a specific form of the protein called “brain-derived tau,” which is specific to Alzheimer’s disease.
The scientists carried out the test on 600 patients in different stages of Alzheimer’s disease, and found that the levels of tau protein in the blood were significantly correlated with the levels of tau in the cerebrospinal fluid analysis, thus Alzheimer’s disease could be reliably distinguished from other neurodegenerative diseases.
The protein levels also correlate closely with the severity of amyloid plaques and tau tangles in the brain tissue of people who died of Alzheimer’s disease.
The next step will be to validate the test in a wider range of patients, including those from diverse racial or ethnic backgrounds, and those with different stages of memory loss or other potential dementia symptoms.
Karikari also hopes that monitoring levels of brain-derived tau in the blood could improve the development of clinical trials for Alzheimer’s therapies.