Patients say they want Alzheimer’s blood tests. Doctors aren’t sure they help.

Health newsPatients say they want Alzheimer’s blood tests. Doctors aren’t sure they help.A survey of nearly 600 adults found that 85% would get an Alzheimer's blood test if their doctor recommended it.Listen to this article with a free account00:0000:00Even if blood tests can accurately predict Alzheimer's risk, they raise a bigger question: what patients should do with the information.Getty ImagesShareAdd NBC News to GoogleApril 27, 2026, 5:00 AM EDTBy Berkeley Lovelace Jr.The idea is straightforward: Take a blood test now, even without symptoms, and learn if you could some day develop Alzheimer’s disease.Subscribe to read this story ad-free Get unlimited access to ad-free articles and exclusive content.Whether you should get this test is a more complicated matter. Most Alzheimer’s blood tests work by measuring levels of amyloid or tau, proteins that build up in the brain and are thought to play key roles in the disease. Both can begin gathering in the brain decades before any symptoms appear.But it’s still an ongoing debate how well the tests can predict who will go on to develop Alzheimer’s disease, doctors say. Some people who test positive never do, fueling suspicion about how reliable the results are in the first place. Even if the tests can accurately predict risk, they raise a bigger question: what should patients do with the information? There is no cure for Alzheimer’s disease, which affects about 7 million people in the U.S., according to the Mayo Clinic. The two drugs approved by the Food and Drug Administration — Leqembi and Kisunla — aim to slow, not cure, the disease. There’s mixed evidence for how well they work, and they come with potentially serious side effects, including brain swelling and bleeding. Diet and exercise may help reduce the risk of Alzheimer’s, but their effects are limited.“The whole idea of doing a test to provide an early diagnosis of any disease is that if we act early, we get better results,” said Dr. Alberto Espay, a...