New Tool Detects Dementia up to Nine Years before Onset and with High Accuracy | Inside Precision Medicine

A new method for predicting dementia has over 80% accuracy and works up to nine years before a diagnosis. Researchers at Queen Mary University of London report. They say the new method provides a more accurate way to predict dementia than memory tests or measurements of brain shrinkage, two commonly used methods for diagnosing this condition. It’s estimated that over 55 million people suffer from dementia worldwide. Early, accurate diagnosis has long been a challenge.

“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,” said Charles Marshall, Professor, and Honorary Consultant Neurologist, who led the research team within the Centre for Preventive Neurology at Queen Mary’s Wolfson Institute of Population Health. 

Their work appears in Nature

The team developed the test by analyzing functional MRI (fMRI) scans for changes in the brain’s “default mode network (DMN).” The DMN connects regions of the brain to perform specific cognitive functions and is the first neural network to be affected by Alzheimer’s disease. 

They had fMRI scans from over 1,100 volunteers from the UK Biobank, a large-scale biomedical database and research resource containing genetic and health information from half a million U.K. participants, to estimate the effective connectivity between ten regions of the brain that constitute the default mode network. 

The researchers assigned each patient a “probability of dementia value” based on the extent to which their effective connectivity pattern conforms to a pattern indicating dementia. They compared these predictions to the medical data of each patient, on record with the UK Biobank. 

They found the model accurately predicted the onset of dementia up to nine years before an official diagnosis was made, and with greater than 80% accuracy. Where participants went on to develop dementia, the model could also predict, within a two-year margin of error, how long it would take that diagnosis to be made.  

The researchers also examined whether changes to the DMN might be caused by known risk factors for dementia. They found that genetic risk for Alzheimer’s disease was strongly associated with connectivity changes in the DMN, supporting the idea that these changes are specific to Alzheimer’s disease. They also found that social isolation was likely to increase the risk of dementia through its effect on connectivity in the DMN. 

It is now more important than ever to detect signs of dementia early.  Life expectancy has increased and many people live into their late 90s.   Prevention and early diagnosis can prevent early disability and allow people to 'age in place' which allows for independent living, avoidance of expensive nursing homes, and allow for improved socialization of aged patients.

New Tool Detects Dementia up to Nine Years before Onset and with High Accuracy | Inside Precision Medicine