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Predicting dementia up to 9 years before diagnosis

Predicting dementia up to 9 years before diagnosis

This is reported by researchers from Queen Mary University in London Nature mental health developing a method for predicting dementia with an accuracy of more than 80%, up to nine years before a diagnosis, and it is suggested that this is a more accurate way of predicting dementia than memory tests or measuring brain shrinkage.

“Predicting who will develop dementia in the future will be critical to developing treatments that can prevent the irreversible loss of brain cells that cause 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 with these proteins in their brains for decades without developing symptoms of dementia. We hope that the measure of brain function we have developed will allow us to determine much more accurately whether someone will actually develop dementia, and how. soon, so we can determine whether they may benefit from future treatments,” said Charles Marshall, professor and honorary consultant neurologist, who led the research team within the Center for Preventive Neurology at Queen Mary’s Wolfson Institute of Population Health.

The study

For this study, fMRI scans from more than 1,100 participants enrolled in the UK Biobank were used to estimate effective connectivity between ten brain regions that form the default mode network (DMN), and changes in the DMN. The DMN connects brain regions to perform specific cognitive functions and is the first neural network affected by Alzheimer’s disease. Participants were assigned a probability value for dementia based on the extent to which their effective connectivity pattern corresponded to a pattern indicative of dementia or a control-like pattern. The predictions were then compared with medical data from the UK Biobank.

What they found

The analysis found that the predictive model accurately predicted the onset of dementia up to nine years before an official diagnosis was made, and with an accuracy of more than 80%. Among those who developed dementia, the predictive tests were found to accurately identify, within a two-year margin of error, how long it would take for the individual to receive a diagnosis.

Risk factors

It was also investigated whether or not changes in the DMN could be caused by known risk factors for dementia. This analysis showed that genetic risk for Alzheimer’s disease (AD) was strongly associated with connectivity changes in the DMN. This finding supports the belief that these changes may be specific to AD. Social isolation was found to be a risk factor likely to increase the risk of dementia through its effect on connectivity in the DMN.

“By using these analysis techniques with large data sets, we can identify those at high risk for dementia, and also learn which environmental risk factors have pushed these people into a risk zone. There is enormous potential to apply these methods to different brain networks and populations , to help us better understand the interplay between environment, neurobiology and disease, both in dementia and possibly other neurodegenerative diseases. fMRI is a non-invasive medical imaging tool and takes about six minutes to acquire the necessary data on an MRI. scanner, so that could be integrated into existing diagnostic pathways, especially where MRI is already used,” says Samuel Ereira, lead author and Academic Foundation Program Doctor at the Center for Preventive Neurology, Wolfson Institute of Population Health.