UNT Health Science Center is conducting the first study of a blood test to detect Alzheimer’s disease in a primary care setting.
Sid O’Bryant heads the Institute for Translational Research at UNT Health Science Center in Fort Worth. He says the current testing for Alzheimer’s involves a lot of steps:
- An exam by a physician
- Referrals to a specialist
- Blood work
- An MRI
“There is a PET scan now to detect the plaque in the brain,” O’Bryant says. “But it’s not reimbursed, so it’s incredibly expensive."
All that can take months and cost thousands of dollars without always producing an accurate diagnosis. O’Bryant is conducting trials on a test of markers in the blood that could be performed in a primary care physician’s office for what he now estimates at about $200. He says the test, so far, has a 90 percent rate of accuracy.
O’Bryant says a quicker, easier and cheaper test for early onset Alzheimer’s has two main benefits: Most people who complain of memory problems don’t have the disease. The test could confirm that. For those diagnosed with Alzheimer’s, knowing early means they can make their own decisions.
“Most people feel better when they know what is going on,” O’Bryant says. “They can plan accordingly. They can get the medications we do have and then they can get connected to all the resources in the community, so that everyone gets help.”
Current testing for Alzheimer’s: Patients need to be referred to a specialist – maybe a geriatrician, a psychiatrist, a neurologist. Medical exam by the physician. Blood work. MRI. There is a PET scan now to detect the plaques in the brain. But it’s not reimbursed, so it’s incredibly expensive and it's research only at the moment. It is FDA-approved. But normally it takes months and thousands of dollars to get a diagnosis.
Is it definitive? No. You come up with a pretty accurate diagnosis, but it could be wrong. The only way to make certain is to do that PET scan or lumbar puncture to know if there are plaques of amyloid in the brain.
How blood test for Alzheimer's works: What we’ve seen in the cancer field is scientists have found these profiles of different markers that put people at risk, and of who could respond to therapy. We took that approach and applied it to Alzheimer's, and what we’ve come up with is a profile of markers in the blood that, if altered and dysfunctional, has over 90 percent accuracy of telling whether someone has Alzheimer's disease.
Cost: It only costs me right now about $200 to run it. A full exam like I just mentioned costs about $1,500 to $3,000. The PET scan costs almost $10,000. So a few hundred bucks is what it should cost. My hope is that we can lower it and get it even cheaper.
Why focus the trial on older adults: Because after talking with CMS (Centers for Medicaid and Medicare), it looks like right now, 65 would be the age at which something like this test would probably be used. My goal is to go younger, because prevention is going to be the long term key.
Goal of the test: We’ve designed this project to look like a primary care doctor would use it. We don’t screen in or screen out whether someone has Alzheimer’s disease. The primary care doctor’s normal thing would be, patient comes in and say “Doc, my memory’s bad. Something’s going on, or something’s changing.” Then the doctor would say, “Do they believe there’s something go on that really requires a test?” And if the doctor truly believes that memory complaint needs to be followed up, they refer them to the project.
Then we do a full exam, including the PET scan, which can’t get reimbursed because it’s so expensive. So we know definitively, when we run people through the study, if they have Alzheimer’s disease.
Benefits of early diagnosis: One is that most people walking into their doctor’s office with memory complaints do not have Alzheimer’s disease. So having a blood test that can tell the doctor that they’re fine is huge. The thing I feel is so important is to be able to make our own decisions. Most people feel better when they know what is going on. They can plan accordingly.
One more possible benefit: The way the field’s going, they’re getting earlier and earlier therapies that are getting tested. So, I think we need to get the blood test now. When these other therapies hit the market in the next few years, the primary care docs have a way to deal with it.