Most older adults say they would agree to a blood test that gauges their Alzheimer's risk, even though almost none have heard of one. That is the central finding of a Northwestern Medicine survey of nearly 600 primary care patients, average age 62, published April 15 in Alzheimer's & Dementia: The Journal of the Alzheimer's Association. Eighty-four percent of respondents were unfamiliar with Alzheimer's blood biomarker tests and fewer than 2% had ever taken one. After a brief explanation of what the tests do, 85% said they would take one if their doctor recommended it.
The study grew out of what Northwestern University psychologist Andrea Russell observed in her work with older adults living with early cognitive impairment. She describes patients consumed by anxiety over ordinary lapses - a forgotten word, a missed appointment - and afraid of slipping up in front of others. Some are too frightened to raise the subject with their own physician at all. That combination of uncertainty and dementia-related stigma prompted her to ask whether people actually want the information a blood test could give them.
The answer matters because blood-based biomarker testing is moving quickly from research settings toward everyday clinical practice, and health systems have to decide how to introduce it. The gap between near-total unfamiliarity and near-universal willingness points squarely at the doctor's office: patients are not asking for these tests because they do not know they exist, but they are receptive once someone explains them.
The survey captured stated willingness in a hypothetical scenario rather than what patients do when a test is actually offered, and the sample was drawn from primary care practices. Still, the results suggest that fear of knowing may be less of an obstacle than clinicians have assumed, and that the harder work lies in explaining what a positive or negative result would and would not mean.