[A blood test might] be a simple way to help diagnose [Alzheimer’s, the] most common form of dementia.
Developing such a test has been a long-sought goal, and scientists warn that the new approach still needs more validation and is not yet ready for wide use.
But [the July 28] results suggest they’re on the right track. The testing was able to differentiate between people with Alzheimer’s and people with other types of dementia, or those with healthy brains, with accuracy ranging from 89% to 98%.
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Dr. Oskar Hansson of Lund University in Sweden led a study of Eli Lilly’s test on more than 1,400 people already enrolled in dementia studies in Sweden, Arizona and Colombia… The p-tau217 test outperformed a host of other measures for indicating which patients had Alzheimer’s as verified by brain scans. It also was comparable to the brain scans and some spinal tests in accuracy.
Dr. Suzanne Schindler of Washington University in St. Louis also found p-tau217 better than some other indicators for revealing which patients had plaques in the brain — the hallmark of Alzheimer’s.
“When patients come to me with changes in their memory and thinking, one of the major questions is, what’s the cause? Is it Alzheimer’s disease or is it something else?” she said. If tau testing bears out, “it would help us diagnose people earlier and more accurately.”