Scientists have announced that they are now one step closer to creating an early-warning blood test for Alzheimer’s disease, but how exactly would it work and who would get the most benefit out of it?
An international team of scientists led by researchers at King’s College London, together with British biomarker research firm Proteome Sciences, have announced that for the first time anywhere in the world they have been able to identify 10 proteins in our blood whose presence seems to predict a patient later developing Alzheimer’s disease, a condition that creates plaques and tangles in the structure of the brain that lead to cognitive impairment and decline.
To devise this test, the scientists analyzed the blood of 452 healthy people, 220 who were classed as having “mild cognitive impairment,” and 476 who had been diagnosed with Alzheimer’s disease.
By focusing on the presence of the aforementioned 10 proteins, classed as biomarkers, the scientists were able to predict with 87 percent accuracy how likely it was that a patient who had cognitive impairment would then go on to develop Alzheimer’s within a year. That might not sound like much of a predictive power, but it could be crucial.
Currently, scientists who are trying to develop drugs to help treat Alzheimer’s face the problem that, with no way to predict who might one day develop the brain disease, they can only test drugs on patients who are already suffering from Alzheimer’s, and the results from those trials have been, well, quite frankly terrible. Over 99 percent of all recent Alzheimer’s trials that aimed at preventing or reversing the disease have failed.
This means that scientists haven’t been able to come up with a way of permanently halting the progress of the disease or reversing some of that decline before it gets too serious.
With this blood test, then, there is finally a possibility of solid early intervention and developing drugs that could tackle the disease before it takes hold, rather than trying to slow its impact once it has already gripped the patient. Researchers are hoping that this test, in particular, will allow them to put those showing mild cognitive impairment with the biomarkers for Alzheimer’s into clinical trials and, hopefully, find a drug that can stop mild impairment developing into Alzheimer’s.
“We want to be able to identify people to enter clinical trials earlier than they currently do and that’s really what we’ve been aiming at,” lead researcher Professor Simon Lovestone from the University of Oxford told the BBC.
Other researchers not involved in this study called it a “big step forward” for Alzheimer’s research. So how close are we to having access to this test? It’s probably about ten years away at the moment and will require a lot more tests on bigger groups of patients before researchers can be sure that the biomarkers’ predictive power work in larger groups–but researchers believe that this test will stand up and that the work can begin relatively swiftly.
The next wave of research will aim at improving what is already a promising level of accuracy for the biomarker detection method, as well as exploring the medical care pathways that should be put in place after someone is told that they have the biomarkers that make them highly likely to develop Alzheimer’s.
Could this test one day find its way into doctors’ surgeries as part of a routine diagnostic tool, then? Lovestone believes that, though it might be a grim thing to know of impending Alzheimer’s in advance, that is a possibility. While the prospect of being told that you have an as yet incurable brain disease, or at least the biomarkers that say you will develop the disease within the next year, is indeed an awful thing, it is known that early intervention with the drugs we already have can at least slow the progress of the disease and so help patients hold on to their quality of life for longer.
In the long term, the researchers believe that there’s a chance that this blood test, or one developed from the work that is being done today, could actually enable routine medical screening for Alzheimer’s, perhaps even years in advance, and could be the stepping stone to making Alzheimer’s a preventable disease.
Given the current state of medical knowledge surrounding Alzheimer’s, that goal still seems far away but the prospect of it, and what it could mean to thousands of people worldwide who suffer from this condition, is tantalizing.
Photo credit: Thinkstock.