Highly Accurate Blood Test Detects Alzheimer's 15 Years Before Memory Loss

We’ve reported on so many early-detection tests for Alzheimer’s disease over the years that it sometimes feels like we’re a broken record. But we can’t forget that one or more of these tests will one day be in regular use in doctors’ offices and clinics around the world to help us detect Alzheimer’s disease in its earliest stages.

Blood tests are among the most effective of these Alzheimer’s early-detection tests, so it’s no surprise that researchers have been trying to home in on the very best blood test for diagnosing the disease.

Recently, a group of researchers claim they found it…

Researchers from the University of Gothenburg in Sweden believe they’ve identified a protein in the blood that’s a more accurate predictor of Alzheimer’s disease than any other.

The team looked at health data on 786 people with an average age of 66, with and without cognitive impairment. Each took a blood test that’s specific for Alzheimer’s disease. The test measures levels of plasma phosphorylated tau 217 or p-tau217.

The Precursor to Amyloid Beta Proteins

Plasma p-tau217 is considered a precursor of amyloid beta proteins and is found in early Alzheimer's disease. When researchers compared plasma p-tau217 to the current gold standard Alzheimer’s detection methods of analyzing spinal fluid obtained via a lumbar puncture (spinal tap), and a PET brain scan, they found p-tau217 was significantly more accurate.

In fact, after eight years the Swedish researchers found that plasma p-tau217 was up to 96 percent and 97 percent accurate respectively, in identifying elevated levels of amyloid and tau. These are considered two hallmarks of Alzheimer’s disease. Researchers believe that the presence of p-tau217 could detect the condition up to 15 years before symptoms start.

But it’s only the beginning….

Predicts Risk Level

The p-tau217 test also categorized people as likely, intermediate, or unlikely to develop Alzheimer’s. This allowed the researchers to predict that only the intermediate group would need follow-up lumbar punctures or brain scans thereby reducing the demand for these expensive and uncomfortable tests by as much as 80 percent.

Nicholas Ashton, first author of the study published in JAMA Neurology in January, explained, saying, “Now we are close to these tests being prime-time and this study shows that.”

Alzheimer's experts in the U.K. were asked to comment on the test developed by the company ALZpath. They were all impressed.

Potential to Revolutionize Diagnosis

Dr. Richard Oakley, Associate Director of Research and Innovation at the Alzheimer’s Society, said: “This blood test would be a crucial step in speeding up how quickly and how early we are able to diagnose [Alzheimer’s] dementia.”

Meanwhile, Dr. Sheona Scales, Director of Research at Alzheimer’s Research U.K., said “…this particular test has huge potential to revolutionize diagnosis for people with suspected Alzheimer’s.”

And Professor Jonathan M. Schott, Professor of Neurology at University College London, also believes “p-tau 271 has the potential to revolutionize the diagnosis of Alzheimer’s disease.”

While Professor David Curtis, also from University College London, said this test “could potentially have huge implications. Everybody over 50 could be routinely screened every few years, in much the same way as they are now screened for high cholesterol.”

The only expert to add a word of caution was Professor Tara Spires-Jones, President of the British Neuroscience Association. Although she said it was “a strong study” it was important to note that “not everyone with (amyloid and tau) pathologies will go on to develop Alzheimer’s dementia.” It’s a good point because this is a proven medical fact that we’ve reported many times before.

Our Takeaway

Any effective early detection test is big news. Some Alzheimer’s researchers were hoping there would be an effective drug protocol. While there aren’t drug interventions that can stop the development of Alzheimer’s, lifestyle interventions are effective. The research shows that 40 percent of dementia cases can be prevented or delayed by modifying 12 risk factors.

We’ve also reported on the remarkable success in restoring brain health in patients following the protocols of Dr. Dale Bredesen, Dr. Richard Isaacson and Dr. Daniel G. Amen

Even with no reason to suspect future dementia we should all be using strategies to prevent it, but sometimes we need to be shocked into taking action. The new blood test, if approved, might do just that.