Alzheimer's Blood Test in the Works
Test May Predict Which Patients With Mild Warning Signs Will Develop Alzheimer's Disease
Oct. 15, 2007 -- Researchers report promising results from a blood test they're developing to predict Alzheimer's disease by up to six years before clinical diagnosis.
The blood test isn't ready for use yet. But it may one day help doctors identify which people with mild memory problems will eventually develop Alzheimer's disease.
So say the researchers, who included Tony Wyss-Coray, PhD, of Stanford University's medical school.
They created a blood test for Alzheimer's disease based on 18 proteins in blood plasma.
Cells use those proteins to communicate with each other, and their communications change as Alzheimer's disease unfolds.
Wyss-Coray and colleagues developed the blood test to detect changes in those 18 proteins that foretell Alzheimer's disease.
"Just as a psychiatrist can conclude a lot of things by listening to the words of a patient, so by 'listening' to different proteins we are measuring whether something is going wrong in the cells," Wyss-Coray says in a Stanford news release.
"It's not that the cells are using new words when something goes wrong," he explains. "It's just that some words are much stronger and some are much weaker; the chatter has a different tone."
The researchers tested 259 plasma samples from people without any memory problems, people with mild cognitive impairment, and Alzheimer's patients.
The blood test was "close to 90% accurate" in identifying the Alzheimer's patients.
Among 47 people with mild cognitive impairment at the time of the blood test, the test was 91% accurate in predicting who developed Alzheimer's disease within two to five years of the blood test.
The findings appear online in Nature Medicine and will be in the journal's November print edition.
The study was partly funded by Satoris Inc., a company that is developing the Alzheimer's blood test.
Wyss-Coray and two of his colleagues founded Satoris Inc. Wyss-Coray is a Satoris Inc. consultant. One of his colleagues worked for Satoris Inc. at the time of the study.