A set of 10 blood proteins which reliably predict the onset of Alzheimer’s has been identified by a new study.
It could lead to a relatively cheap and non-invasive test for the disease within a few years.
At the moment the early stages of Alzheimer’s can be difficult to tell apart from the normal ageing process, until it is too late.
Only around 10% of older people with mild cognitive impairment go on to develop dementia within a year.
One of the study’s authors, Professor Simon Lovestone, explained:
“Alzheimer’s begins to affect the brain many years before patients are diagnosed with the disease.
Many of our drug trials fail because by the time patients are given the drugs, the brain has already been too severely affected.
A simple blood test could help us identify patients at a much earlier stage to take part in new trials and hopefully develop treatments which could prevent the progression of the disease.”
The new test, which could be available within two years, can predict the onset of Alzheimer’s in the next year with 87% accuracy.
This would enable drugs to be prescribed earlier and likely improve outcomes.
Finding the right proteins
The study used blood samples from 1,148 people (Hye et al., 2014).
Some had Alzheimer’s, others a mild cognitive impairment and some were elderly controls without dementia.
By analysing the blood samples, they found 10 proteins that could predict the progression from mild cognitive impairment to Alzheimer’s.
The study’s lead author, Dr Abdul Hye, said:
“Memory problems are very common, but the challenge is identifying who is likely to develop dementia.
There are thousands of proteins in the blood, and this study is the culmination of many years’ work identifying which ones are clinically relevant.
We now have a set of 10 proteins that can predict whether someone with early symptoms of memory loss, or mild cognitive impairment, will develop Alzheimer’s disease within a year, with a high level of accuracy.”
Previous studies have found that PET scans and lumbar punctures can predict the onset of dementia, but the former is very expensive and the latter invasive.
A blood test would provide a more cost-effective and less invasive test for a disease which is thought to affect 115 million people around the world.
Image credit: Bev Sykes