Most Older Adults Would Take an Alzheimer’s Blood Test, Study Finds

Would you take an Alzheimer’s blood test if your doctor recommended it? 

These tests measure beta-amyloid and tau proteins in the blood as part of a diagnostic workup in those with memory and thinking problems. While the FDA has cleared two blood tests, many others with varying levels of accuracy are also available for doctors to order. 

Since the tests are still new, Andrea Russell, a psychologist at Northwestern University, wondered whether knowledge of them had trickled down to the average person in primary care. 

Her new study, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, surveyed over 600 healthy older adults, average age of 62. Among them, over four in five said they would take a blood test if recommended by a doctor. 

“We needed to know a lot more about patients’ attitudes and their perceptions towards these tests,” Russell told Being Patient. If the tests become more widespread, then this knowledge could help doctors understand people’s concerns and spot any access barriers.

What do people think about Alzheimer’s blood tests?

Russell surveyed a diverse group of participants, of whom 28 percent were Black and 11 percent were Latino Americans. Almost 84 percent said they were not familiar with Alzheimer’s blood tests.

The survey briefly explained that blood tests are a new way to tell if someone is at risk for Alzheimer’s, but cautioned that the tests don’t provide a definitive diagnosis.

After the explanation, 94.5 percent of participants thought it was “very important” or “somewhat important” to offer these tests to those with memory or thinking problems in primary care. Almost 85.5 percent said they’d take it if their doctor recommended one, similar to another recent survey.

Russell’s study also found that people would be more willing to take the blood test if it informed medical care, if it was covered by insurance, and if doctors provided information about it beforehand. People with three or more chronic health conditions were more likely to say yes to the test. 

Another 35 percent were concerned about test reliability, 24 percent were concerned about being treated differently after testing positive, while about 22 percent worried about a false positive test.

If they received a positive test, 87 percent said they would be “very likely” to take steps to improve brain health, while more than a quarter said they’d be “very likely” to experience emotional distress. Other studies suggest the distress is short-lived, but also that people who test positive for Alzheimer’s biomarkers won’t engage in healthy behaviors as much as they initially think they would. 

Understanding the limitations of blood tests

A quarter of participants believed it was “very likely,” and over 50 percent “somewhat likely,” that they would develop Alzheimer’s upon receiving a positive test. However,many with these biomarkers never develop cognitive symptoms.

“Up to a third of people with positive amyloid PET scan die cognitively normal,” Dr. Andrea Bozoki, neurologist, and chief of the University of North Carolina at Chapel Hill’s division of Memory and Cognitive Disorders, who wasn’t involved in the study, told Being Patient.

Among the participants, over 60 percent said it was “very important” to offer the test to anyone over 65 while about 27 percent said it was “somewhat important.” Neurologists typically caution against such tests in cognitively healthy individuals since it isn’t yet clear what a positive test means for those individuals.

A 2025 study tested more than 2,000 healthy older adults and found that only 43 percent of those who tested positive developed Alzheimer’s within the next 10 years. 

Bozoki said that many physicians have trouble with the idea that the ability of these tests to predict who will develop Alzheimer’s depends largely on who is being tested rather than the numbers describing the accuracy of a test. 

A small percentage of her referrals over the last few months have been cognitively healthy adults whose primary care doctor inappropriately ordered a blood test that came back positive, she said. She tells these patients that she doesn’t know if or when they’ll develop cognitive decline but encourages them to join clinical trials.

Bring blood tests into primary care

Right now, blood tests aren’t routinely used in primary care. Guidelines from experts convened by the Alzheimer’s Association recommend their use only by neurologists, while other guidelines recommend tests that reach a certain level of accuracy for primary care. 

Roche’s pTau-217 test is currently cleared for use in primary care as a tool to rule out people who don’t have Alzheimer’s. 

If they are rolled out in primary care, doctors will need to be up for the challenge. With limited time to speak with each patient, Dr. Nathaniel Chin, a neurologist and co-director of the Wisconsin Alzheimer’s Disease Research Center, said it would be challenging to counsel patients about the potential benefits and drawbacks of these tests.

He recalls one patient whose doctor ordered a blood test and referred them to his neurology clinic. After the patient and family learned the results, they had to wait three months to see Chin without any guidance by the doctor.

Russell’s survey showed that people clearly want information about their cognitive health, but the question is can doctors provide enough support. “The health system demands too much of primary care providers,” she said. “They need more time with their patients.”