Alzheimer's Blood Test Could Have 'Huge Implications'

A blood test already available to researchers can detect potential Alzheimer's disease patients with very high accuracy, scientists say. According to a study published in the journal Jama Neurology, the simple blood test can detect p-tau217, a key biomarker for the disease, with up to 97% accuracy. The protein starts to build up in the brain up to 15 years before people with Alzheimer's start showing symptoms, CNN reports. Since the test is far cheaper and less invasive than a spinal tap, experts say it could open the door to widespread screening for the disease—and when blood tests are negative for tau, it could speed up the investigation for other causes of symptoms like memory loss.

"Everybody over 50 could be routinely screened every few years, in much the same way as they are now screened for high cholesterol" says David Curtis, an honorary professor at the University College London Genetics Institute who was not involved with the study. "It is possible that currently available treatments for Alzheimer's disease would work better in those diagnosed early in this way." Curtis says that when better treatments for halting the progression of the disease become available, it will be vital to identify those most at risk, meaning this study could "potentially have huge implications."

Researchers looked at data on 786 people who averaged 86 years old. Some, but not all, of the participants showed signs of cognitive decline. Sheona Scales, director of research at Alzheimer's Research UK, says this particular test has huge potential to revolutionize diagnosis for people with suspected Alzheimer's. The test developed by the company ALZpath is currently only available to researchers, but the company aims to make it available for clinical use soon, with an estimated cost of $200 to $500, reports CNN. (More Alzheimer's disease stories.)