Alzheimer's disease: a blood test for early detection

Japanese and Australian scientists have developed a blood test that can detect early accumulation of toxic proteins related to Alzheimer's disease.

A blood test to detect Alzheimer 's disease has been developed and would be 90% effective, according to the results of a study published in the medical journal Nature . Today, there is no treatment to change the course of Alzheimer's disease, but screening tests may be useful today for clinical trials.

Alzheimer's disease develops years before patients experience symptoms of memory loss. The key to treating dementia would be to intervene earlier before the permanent degradation of brain cells. For this, a lot of research on tests for Alzheimer's disease is underway.

One method is to look for a toxic protein, a bio-marker of the disease, called beta-amyloid, that builds up in the brain during the pathology.

It can be detected by MRI in patients with Alzheimer's symptoms. But this method is expensive and is only possible once the disease is diagnosed and declared.

90% EFFECTIVE BLOOD TEST

To measure fragments of amyloid circulating in the bloodstream, Katsuhiko Yanagisawa, director general of the National Center for Geriatrics and Gerontology in Japan, used a technique called immunoprecipitation with mass spectrometry, which deploys antibodies to bind and identify proteins. . The study included 121 people from Japan and 252 from Australia. Both groups included healthy individuals, people with mild cognitive impairment, and Alzheimer's disease. The researchers observed that the amount of amyloid present in the blood was correlated with the degree of cognitive problems and was also identical to the results of the scans and cerebrospinal fluid measurements of the same patients. It was 90% accurate.

This blood test would provide a less expensive and less invasive way to determine the amyloid status of a patient. This could encourage more patients to participate in clinical trials. It could also help researchers distinguish between people who develop Alzheimer's disease and those who have other forms of dementia.

"We believe that amyloid blood tests could replace expensive invasive amyloid tests, particularly when it comes to detecting preclinical Alzheimer's disease ," the researcher said. "We hope our biomarker will facilitate clinical trials for [Alzheimer's] by improving participant enrollment."