Is a reliable blood test for Alzheimer’s disease finally here?

A study published in JAMA in July 2024 found that a blood test was accurate in diagnosing Alzheimer’s disease, which causes steep declines in cognition and other aspects of health. The blood test is able to detect elevated blood levels of brain proteins that characterize the condition. While that’s progress, doctors say it’s not the test needed most. It would be more beneficial, they say, to have a test that accurately spots the developing disease long before it affects thinking. No such tests are here yet, but scientists are working to develop them.