New blood test offers hope for Alzheimer’s screening
Affordable testing for the early signs of Alzeimer’s disease has been a hope of medicine for decades.
Now a simple blood test may provide the answer, according to a new study published in JAMA Neurology.
Researchers looked at data from 786 people in the US, most of whom were aged 66 and enrolled in studies of Alzheimer’s disease (AD).
A blood test that measured a protein called phosphorylated tau (p-tau) showed it was accurate in 97% of cases.
Until recently, doctors have been relying on expensive or intrusive procedures, like positron emission tomography (PET) or a spinal tap for cerebrospinal fluid (CSF), to detect brain changes commonly seen in Alzheimer’s patients.
The latest study compared blood test data to results obtained from CSF with comparable results.
A blood biomarker would enable an earlier and more precise AD diagnosis, potentially leading to patients being able to access treatments more quickly.
Researchers concluded that p-tau is now the leading blood biomarker, showing superior diagnostic ability compared to other biomarkers.
Alzheimer’s is the most common form of dementia, affecting nearly one million people in the UK.
Scientists have been studying for decades two potential biological culprits in the progression of the condition. One would-be culprit is the protein tau, found in tangles in the brains of affected people. The other contender, and a target of intense study, is amyloid plaques.
Dr Richard Oakley, Associate Director of Research & Innovation at Alzheimer’s Society described the test as critical to earlier diagnosis, in a statement distributed by the Science Media Center.
Dr Oakley also said: “This study is a hugely welcome step in the right direction, as it shows that blood tests can be just as accurate as more invasive and expensive tests at predicting if someone has features of Alzheimer’s disease in their brain.”
“Coming down the line are potentially ground-breaking new drugs which can slow the progression of early-stage Alzheimer’s disease. But for people to be eligible for them if they’re approved in the UK, they will need an early, accurate diagnosis.”
The UK is launching the Blood Biomarker Challenge, thanks to £5m in funding from the People’s Postcode Lottery to gather the information needed to introduce a blood test for dementia into UK healthcare systems.
Dr Sheona Scales, Director of Research at Alzheimer’s Research UK, added:
“People with dementia frequently face unacceptably long delays getting a diagnosis and, with new treatments finally on the horizon, it’s never been more important to transform the way people with potential symptoms of Alzheimer’s are diagnosed.
“In the past year, we have seen incredible progress in the development of blood-based Alzheimer’s tests. And as we see more and more different types of tests becoming available, studies like this are key to understanding which are most accurate.”
In the meantime, there are simple tips to maintain brain health, including healthy brain snacks.