Study: Blood Test Detects Early Alzheimer's
Experimental Test Checks for Signs of Plaque in Brain
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Blood Test for Plaque
To develop the noninvasive blood test, Burnham and colleagues used blood samples from 273 people participating in a large-scale study looking for new biomarkers for dementia.
First, they identified nine proteins that correlated with the amount of amyloid deposited in the brain.
"We set a cutoff level. Anyone above that point is thought to go on to get Alzheimer's disease in the next eight to 10 years. Anyone below that [level] is safe," she says.
When the blood test was administered to the same 273 participants, it correctly identified 83% of people with abnormally high levels of amyloid, as confirmed by PET scans. It also correctly identified 85% of people who didn't have high levels.
"That's pretty accurate when you consider that brain scans are only about 90% accurate," Burnham says.
The test was validated in 74 people participating in a U.S. study looking for Alzheimer's disease biomarkers.
Burnham doesn't know how much the new test will eventually cost, but points out that blood tests are typically inexpensive. She adds that CSIRO, which has a patent on the test, has approached several companies about commercial development.
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.