Venu Menon
Wellington, February 1,2024
A simple blood test can detect the onset of Alzheimer’s disease 10 to 15 years in advance, according to a study cited by the Times of London.
Scientists in Sweden have devised a test kit capable of spotting abnormal proteins in the blood that cause Alzheimer’s and offers “a comparatively painless, less costly alternative to spinal taps for insights into a person’s risk of the disease.”
The World Health Organisation (WHO) estimates that Alzheimer’s disease and dementia, combined, affect 55 million people worldwide.
In New Zealand, about 70,000 people suffer from dementia conditions, which is projected to increase to almost 170,000 by 2050.
Cognitive decline is among the earliest symptoms associated with Alzheimer’s disease and dementia ( an umbrella term for a group of conditions that affect the brain, causing memory loss and other changes to brain function).
Clinical studies, conducted by neurological scientists from Sweden’s University of Gothenburg, on 768 participants, with an average age of 66, showed that the blood test delivered “high diagnostic accuracy” in identifying proteins within the brain that caused Alzheimer’s.
“What was impressive with these results is that the blood test was just as accurate as advanced testing like cerebrospinal fluid tests and brain scans at showing Alzheimer’s disease pathology in the brain,” said lead author of the study Nicholas Ashton, adding, “Now we are close to these tests being prime-time and this study shows that.”
The test can detect the presence of abnormal proteins [known as tau proteins] with an accuracy rate of up to 97%.
Experts lauded the blood test as a breakthrough with practical implications to the daily practice of treating Alzheimer’s patients.
The test allowed researchers to determine if people were predisposed at an early age to fall victim to Alzheimer’s disease when they are 50, 60 or 70-years-old.
Another advantage was that the study used a testing kit that was already in the market for medical professionals.
UK-based researcher Sheona Scales noted the study was comparable in terms of results to existing, more invasive practices.
“This study suggests that measuring levels of a protein called p-tau 217 in the blood could be as accurate as currently used lumbar punctures for detecting the biological hallmarks of Alzheimer’s disease, and superior to a range of other tests currently under development.
“This adds to a growing body of evidence that this particular test has huge potential to revolutionise diagnosis for people with suspected Alzheimer’s,” Scales was quoted as saying.
Researchers suggested GPs could perform the blood test in the future as a standard first measure on patients keen on assessing their mental health status.
“Everybody over 50 could be routinely screened every few years, in much the same way as they are now screened for high cholesterol,” said Prof David Curtis of UCL Genetics Institute in London.
As part of the new study, participants were grouped into those who were very likely to have Alzheimer’s, those who were very unlikely to have the disease, and an intermediate group who would need further tests using conventional methods such as lumbar punctures or Positron Emission Tomography (PET) scans.
Researchers predicted using a blood test could reduce the demand for follow-up tests by around 80%.
The new testing procedure, created by the US-based company ALZpath, “can help healthcare providers determine the presence of amyloid plaques in the brain – a hallmark of Alzheimer’s disease,” noted Dr Andreas Jeromin, the company’s chief scientific officer.
ALZpath hoped to make the blood test kit available for clinical use by the end of April 2024.
Venu Menon is an Indian Newslink reporter based in Wellington
