A world-first test for Alzheimer's disease has been developed by scientists in Australia and Japan using mass spectrometry technology to detect the disease decades before symptoms appear.
 
The high tech blood test measures an abnormal peptide in the brain called beta-amyloid that begins to build-up about 30 years before the outward signs of dementia, such as memory loss or cognitive decline, have begun.
 
Current tests for Alzheimer's – brain scans with radioactive tracers or spinal fluid taken via lumbar puncture – are invasive and expensive. The new test will not only make diagnosis cheaper, earlier and more available, it will also fast track research discoveries into the disease.
 
“This new test has the potential to eventually disrupt the expensive and invasive scanning and spinal fluid technologies. In the first instance, however, it will be an invaluable tool in increasing the speed of screening potential patients for new drug trials,” Laureate Professor Colin Masters from Melbourne’s Florey Institute of Neuroscience and Mental Health said.
 
“Progress in developing new therapeutic strategies for Alzheimer’s disease has been disappointingly slow. None of the three drugs currently on the market treat the underlying disease. New drugs are urgently required, and the only way to do that is to speed up the whole process.”
 
The testing breakthrough came about as a result of an international collaboration between industry and academia, with results validated on 252 Australian and 121 Japanese patients.
 
Using high-tech mass spectrometry technology, known as IP-MS, scientists identified patients with the rogue peptide in their blood plasma, indicating a build-up of beta-amyloid in the brain, with 90 per cent accuracy.
 
Dr Koichi Tanaka from Japanese medical technology company Shimadzu Corporation was awarded the Nobel Prize in Chemistry in 2002 for developing the blood testing procedure.
 
“From a tiny blood sample, our method can measure several amyloid-related proteins, even though their concentration is extremely low. We found that the ratio of these proteins was an accurate surrogate for brain amyloid burden,” Tanaka said.
 
The implications for this test and the future treatment of the disease are significant given its devastating impact:

  • Between 20-40 per cent of those over 70 years old have beta-amyloid build-up in their brain and are considered at risk of developing Alzheimer’s disease
  • Dementia is the second largest cause of death in Australia
  • In 2016, dementia became the leading cause of death among Australian females, surpassing heart disease. Women account for 64.4 per cent of dementia-related deaths
  • Without a medical breakthrough, the number of people with dementia is expected to increase to more than 530,000 by 2025
  • In 2018, dementia is estimated to cost Australia more than $15 billion.

 
The new test may also go on to help determine the pace at which a patient with Alzheimer's will deteriorate, and how effective treatments developed in future are at clearing beta-amyloid build-ups.
 
In Australia, the study was conducted by a partnership of the Florey Institute, The University of Melbourne, CSIRO, Edith Cowan University and Austin Health.
 
The research was published today in the journal Nature.