Noninvasive Biomarkers of AD Will Soon Be Reality

Hi. I am Dr Richard Isaacson, a neurologist and director of the Alzheimer's Prevention Clinic at Weill Cornell Medicine and NewYork-Presbyterian Hospital in New York City.

You may have heard the news about a new blood test that can actually predict whether or not a person has amyloid in the brain. Wouldn't it be great if we could use something simple like a blood test to actually know whether a person is exhibiting symptoms of Alzheimer's disease (AD) rather than a different dementia or another medical condition?

Most people in clinical practice, including myself, rely on the simple things to diagnose AD—the clinical history, for example. If the patient comes in and reports a slowly progressive cognitive decline, most specifically with short-term memory and maybe changes in sleep or mood that are progressive over time, we will rule out a thyroid or B₁₂ deficiency and other typical medical causes, and we use MRI or CT to make sure nothing funny is going on in the brain. Common things happen commonly; progressive short-term memory loss in an older person, especially a person with a family history, is most likely to be AD. However, this is not always the case.

Thus, everyone is looking for that one test that can prove whether or not a person has AD, to stratify that person and help decide whether to recommend a clinical trial or an FDA-approved drug for AD.