Dear Angel,
There’s been so much talk about the new Alzheimer’s drug that was just approved by the FDA. I’m wondering– what progress has been made when it comes to early detection of Alzheimer’s, before symptoms arise?
Thanks!
Earl E. Detexion
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Dear Earl,
June is Alzheimer’s and Brain Awareness Month, a time when we help raise awareness about Alzheimer’s disease, as well as show support for the millions of people worldwide living with it or another form of dementia.
It’s been more than a century since Dr. Alois Alzheimer identified the hallmarks of Alzheimer’s — amyloid plaques and tau tangles. The Alzheimer’s community is understandably frustrated with the progress of research, but there is reason for optimism, including a new drug that was recently released and approved by the FDA that is causing mixed emotions. Please read Mr. Farr’s article from today about the newly approved Alzheimer’s drug, aducanumab.
Advances in Alzheimer’s Research and Diagnostics
Dr. Jason Karlawish, co-director of the Penn Memory Center and author of “The Problem of Alzheimer’s,” recently addressed the subject of early detection of Alzheimer’s and where we are when it comes to diagnosis before symptoms arise.
Dr. Karlawish noted that scientists have made tremendous improvements in diagnosing Alzheimer’s. There are now PET scans that measure amyloid and tau in living patients, and blood tests for these biomarkers are under rapid development. According to Dr. Karlawish, right now, we’re still at the point where we can diagnose Alzheimer’s because a patient has some cognitive problems, and tests can show if you have the biological markers. If you have mild cognitive impairment, that can be diagnosed, as well. However, if you don’t have cognitive problems, doctors don’t run tests to see if you do or don’t have Alzheimer’s disease, so if someone is “asymptomatic” or not showing signs yet, they wouldn’t know if they had it or not.
A Promising Blood Test is On the Horizon for Alzheimer’s Diagnosis
This past year, researchers moved closer than ever before to developing a blood test that doctors can use to detect Alzheimer’s disease.
In October 2020, C2N Diagnostics, a company based on the work of Randall Bateman, MD, and David Holtzman, MD, of Washington University in St. Louis, announced the launch of PrecivityAD, the first widely available blood test to help clinicians diagnose Alzheimer’s before symptoms appear.
The test looks at the ratio of two amyloid-beta isoforms and the presence of APOE. The results form a score that indicates the probability of being amyloid-positive on PET imaging. The score correctly identified amyloid status (determined by PET scans) in 86% of 686 older adults with cognitive impairment or dementia, the company said.
PrecivityAD is not a stand-alone diagnostic tool. It was introduced as a laboratory developed test regulated under the CMS Clinical Laboratory Improvement Amendments (CLIA) program and received FDA breakthrough designation, but is not FDA-approved, though that’s in the works.
Will At-Home Alzheimer’s Blood Tests Become Available?
The potential for at-home Alzheimer’s testing is also there. In an article for JAMA Neurology, Dr. Karlawish and his colleagues wrote that “there would likely be at-home blood tests that detect Alzheimer’s pathology in the future, but there are many implications to consider.” He believes that it’s only a matter of time before a blood test for Alzheimer’s pathology becomes a direct-to-consumer test. He doesn’t like the idea of at-home tests that test for biomarkers, because he’s worried about the implications of them. Dr. Karlawish cautions, “(w)e don’t live in a society that is designed to support people who are disabled or at risk of disability. You can be fired. You can lose insurance. You can be stigmatized. This is not a nurturing society that fosters solidarity. The deep irony of these direct-to-consumer tests is, ‘I’m going to give you knowledge that empowers you in a culture in a society that doesn’t support you.’”
Early Detection is Very Important!
Despite Dr. Karlawish’s concerns, early detection is very important. Whether or not the blood test described will be approved, or if there will be home blood tests, or other accurate ways to detect Alzheimer’s before symptoms arise, there is still real value to early detection, including being able to plan in advance for yourself and your loved ones. For now, go to your annual checkups and let your doctor know if you are experiencing any symptoms. For more details on early detection of Alzheimer’s and symptoms to look out for, please read Mr. Farr’s article on the subject.
Hope this helps!
Angel
About Renee Eder
