“This blood test clearly identifies Alzheimer’s tau tangles, which is our best biomarker measure of Alzheimer’s symptoms and dementia,” co-senior author Dr. Randall Bateman, a professor of neurology at the Washington University School of Medicine in St. Louis, said in a news release.

W ith two new treatments for Alzheimer’s disease approved in recent years, there’s growing hope for people at risk of the memory-robbing condition. But tests to detect the condition still lag behind. Earlier diagnosis would mean that people could take advantage of the drugs sooner, when the medicines are most effective.