Blood test 'major step forward' in Alzheimer's
A blood test to predict if someone will develop Alzheimer's within a year has been created, in a breakthrough that raises hopes that the disease could become preventable.
After a decade of research, scientists at Oxford University and King's College London in the United Kingdom are confident they have found 10 proteins which show the disease is imminent.
Clinical trials will start on people who have not yet developed Alzheimer's to find which drugs halt its onset.
The blood test, which could be available in as little as two years, was described as a "major step forward" by Britain's Health Secretary, Jeremy Hunt, and charities, which said it could revolutionise research into a cure.
"Although we are making drugs, they are all failing. But if we could treat people earlier it may be that the drugs are effective," said Simon Lovestone, professor of translational neuroscience at Oxford.
"Alzheimer's begins to affect the brain many years before patients are diagnosed with the disease. If we could treat the disease in that phase we would in effect have a preventative strategy."
Clinical trials into "wonder drugs" such as BACE inhibitors and anti-amyloid agents have shown little improvement for sufferers and scientists believe that by the time Alzheimer's is diagnosed, an irreversible "cascade" of symptoms has already occurred.
Alzheimers New Zealand, a non-profit organisation with 21 branches, said about 50,000 people had dementia in New Zealand. Alzheimer's is one of several hundred types of the disease.
The new test, which examines 10 proteins in the blood, can predict with 87 per cent accuracy whether someone suffering memory problems will develop Alzheimer's within a year.
Researchers used data from three international studies. Blood samples were taken from 1148 people, 476 of whom had Alzheimer's, 220 with memory problems, and a control group of 452 without any signs of dementia.
The scientists found that 16 proteins were associated with brain shrinkage and memory loss and 10 of those could predict whether someone would develop Alzheimer's.
"Developing tests and biomarkers will be important steps forward in the global fight against dementia as we search for a cure," Hunt said.
Previous studies have shown that PET brain scans and plasma in lumbar fluid could be used to predict the onset of dementia from mild cognitive impairment.
But PET imaging is highly expensive and lumbar punctures are invasive and carry risks.
Lovestone said it was unlikely that GPs would use the test until a treatment was available because of potential ethical questions about telling patients potentially devastating news.
The breakthrough was welcomed by dementia charities and academics in New Zealand.
"Early diagnosis and detection of all forms of dementia, including Alzheimer's disease, is critically important in the treatment and management of the condition, and is something that we advocate strongly for," Alzheimer's New Zealand executive director Catherine Hall said. with Telegraph Group
The Dominion Post