A short 5-minute scan of blood vessels in the neck could predict cognitive decline 10 years before symptoms appear, according to research co-funded by the British Heart Foundation.
If the findings are confirmed in larger studies, the scan could be used to help doctors spot patients who might be at high risk of developing dementia earlier than was previously possible.
As the heart beats, it generates a physical ‘pulse’ that travels around the body in a ripple like fashion. Healthy, elastic vessels near the heart usually diminish the energy carried by this pulse by cushioning each heartbeat, preventing the pulse from reaching delicate blood vessels elsewhere in the body.
Factors like ageing and high blood pressure cause stiffening of these blood vessels, and this may diminish their protective effect. As a result, a progressively stronger pulse can travel deep into the fragile vessels which supply the brain.
Over time, this can cause damage the small vessels of the brain, structural changes in the brain's blood vessel network and minor bleeds known as mini strokes, which all may contribute to the development of dementia.
An international team of researchers, led by UCL Professor John Deanfield studied a group of 3,191 middle-aged volunteers who were given an ultrasound in 2002 which measured the intensity of the pulse travelling towards their brain. Over the next 15 years, researchers monitored the participants memory and problem-solving ability.
Study volunteers with the highest intensity pulse (top 25%) travelling towards the brain at the beginning of the study were around 50% more likely to exhibit accelerated cognitive decline over the following decade compared to the rest of the volunteers. The researchers controlled to factors which might also contribute to cognitive decline, like age, BMI, blood pressure and diabetes.
One of the researchers, Dr Scott Chiesa from UCL, said: “These findings demonstrate the first direct link between the intensity of the pulse transmitted towards the brain with every heartbeat and future impairments in cognitive function.
“It’s therefore an easily measurable and potentially treatable cause of cognitive decline in middle aged adults which can be spotted well in advance.”
The researchers now plan to use MRI scans to check if these individuals also display structural and functional changes within the brain, which may explain the changes in cognitive abilities. They also plan to test whether the scan improves predictive ‘risk scores’ for dementia which already exist.
The research was funded by the British Heart Foundation, Medical Research Council (MRC), National Institutes of Health (USA), European Commission (EU), Helsinki Institute of Life Sciences (Finland) and Brain Protection Company Ltd (Australia).