NEW BLOOD TEST FOR ALZHEIMER’S
I try to keep you and me caught up on the latest Alzheimer’s disease news. Here’s information on a new blood test for Alzheimer’s that is both accurate and affordable:
Earlier this year a blood test developed by neurologist Randall J. Bateman, MD, at Washington University School of Medicine, St Louis was shown to be highly accurate—up to 93%—at identifying people at risk of Alzheimer’s. In May 2022 it was approved by the FDA.
Here are excerpts from the Washington University School of Medicine article by Gerry Everding; Blood test for Alzheimer’s highly accurate in large, international study:
“Our study shows that the blood test provides a robust measure for detecting amyloid plaques associated with Alzheimer’s disease, even among patients not yet experiencing cognitive declines,” said Bateman.
“A blood test for Alzheimer’s provides a huge boost for Alzheimer’s research and diagnosis, drastically cutting the time and cost of identifying patients for clinical trials and spurring the development of new treatment options,” Bateman said. “As new drugs become available, a blood test could determine who might benefit from treatment, including those at very early stages of the disease.”
The blood test assesses whether amyloid plaques have begun accumulating in the brain based on the ratio of the levels of the amyloid beta proteins Aβ42 and Aβ40 in the blood.
Low-Cost, Easily Accessible Blood Test
Researchers have long pursued a low-cost, easily accessible blood test for Alzheimer’s as an alternative to the expensive brain scans and invasive spinal taps now used to assess the presence and progression of the disease within the brain.
Evaluating the disease using PET brain scans – still the gold standard – requires a radioactive brain scan, at an average cost of $5,000 to $8,000 per scan. Another common test, which analyzes levels of amyloid-beta and tau protein in cerebrospinal fluid, costs about $1,000 but requires a spinal tap process that some patients may be unwilling to endure.
This study estimates that prescreening with a $500 blood test could reduce by half both the cost and the time it takes to enroll patients in clinical trials that use PET scans. Screening with blood tests alone could be completed in less than six months and cut costs by tenfold or more, the study finds.
Known as Precivity AD, the commercial version of the test is marketed by C2N Diagnostics, a Washington University startup founded by Bateman and his colleague David Holtzman, MD.
The current study shows that the blood test remains highly accurate, even when performed in different labs following different protocols, and in different cohorts across three continents.
“These results suggest the test can be useful in identifying nonimpaired patients who may be at risk for future dementia, offering them the opportunity to get enrolled in clinical trials when early intervention has the potential to do the most good,” Bateman said. “A negative test result also could help doctors rule out Alzheimer’s in patients whose impairments may be related to some other health issue, disease or medication.”