Drop of blood that can detect dementia
Test could diagnose disease ‘years before symptoms’
A SIMPLE test could diagnose Alzheimer’s using just one drop of blood – and up to five years before symptoms develop.
Experts hope the breakthrough, costing pennies, could be rolled out like rapid Covid tests.
It comes after scientists identified chemicals in the blood that act as warning signs for dementia.
Diagnosis of the disease at present relies heavily on memory and thinking tests, but the new technique could mean a single drop of blood could predict who will suffer from it. Early detection is important because it hugely increases the chances of treat- ment being effective.
Researchers measured levels of microRNAs – molecules which influence the production of proteins in the body – in healthy individuals and elderly people with mild cognitive impairment.
They found that the levels of three specific microRNAs were linked with mental fitness in healthy people.
The lower the levels of these molecules in the blood, the better they performed in cognition tests. of those in the study with high levels of the chemicals, 90 per cent went on to develop Alzheimer’s within two years.
The research team said their findings indicate the presence of these microRNAs is not just a warning signal – they could actively influence the development of the disease.
The molecules influence inflammatory processes in the brain and ‘neuroplasticity’ – the brain’s ability to change and adapt over time. This means they could also become potential targets for therapy. Study leader Andre Fischer, of University Medical Centre Gottingen in Germany, said: ‘We see an increased blood level of these three microRNAs as a harbinger of dementia.
‘We estimate that in humans this biomarker indicates a development that is about two to five years in the future.
‘We intend to develop a simple test procedure for point-of-care screening. Our goal is to have a low-cost test, similar to the rapid test for Covid, with the difference being that for our purposes you would need a drop of blood.
‘Such a test could be used during routine check-ups in doctors’ practices to detect an elevated risk of dementia early on.’
He added that when symptoms of dementia become noticeable the brain has already been ‘masAnd sively damaged’, stressing: ‘Presently diagnosis happens far too late to even have a chance for effective treatment. If dementia is detected early, the odds of positively influencing the course of the disease increase.’
Alzheimer’s and other forms of dementia affect 920,000 Britons – a figure set to rise to two million by 2050. At present there is no cure for the disease, but medicines reduce symptoms. The findings were published in the journal EMBO Molecular Medicine.