Scientists in London have developed the first test that can predict dementia up to nine years before diagnosis with 80 per cent accuracy.
The test developed by researchers at Queen Mary University is more accurate than memory tests or measurements of brain shrinkage, two commonly used methods for diagnosing dementia.
There are currently an estimated 982,000 people living with dementia in the UK and the figure is projected to rise to 1.4 million in 2040, according to the Alzheimer’s Society. Early diagnosis can help the patient and caregiver learn about the disease and make plans for the future.
The team at Queen Mary, led by Professor Charles Marshall, looked at brain scans from more than 1,100 people from UK Biobank, a database containing genetic and health information from half a million people in the UK.
They analysed changes in a part of the brain called the default mode network, which connects different regions of the brain to perform specific cognitive functions. It is the first network in the brain to be affected by Alzheimer’s.
Among the 103 people who had dementia, 81 had brain scans between five months and 8.5 years before being officially diagnosed.
These scans showed decreased connectivity in the default mode network compared with those who did not develop dementia, the study showed.
The model created by the team was 80 per cent accurate at predicting which patients would go on to develop dementia.
In the cases where the volunteers had gone on to develop dementia, it was also found that the model could predict within a two-year margin of error exactly how long it would take that diagnosis to be made.
Social isolation was also found to increase the risk of dementia as it impacted connectivity in the default mode network, the study found.
Prof Marshall, who led the research team within the Centre for Preventive Neurology at Queen Mary’s Wolfson Institute of Population Health, said: “Predicting who is going to get dementia in the future will be vital for developing treatments that can prevent the irreversible loss of brain cells that causes the symptoms of dementia.
“Although we are getting better at detecting the proteins in the brain that can cause Alzheimer’s disease, many people live for decades with these proteins in their brain without developing symptoms of dementia.
“We hope that the measure of brain function that we have developed will allow us to be much more precise about whether someone is actually going to develop dementia, and how soon, so that we can identify whether they might benefit from future treatments.”
The findings are published on Thursday in the journal Nature Mental Health.
