Healthy brains age in a similar way to our bodies, with elements such as the amount of grey matter changing as people get older. In the past 10 years researchers have developed algorithms which can learn to recognise this typical pattern of ageing in the human brain. Once an algorithm has learned what healthy brain ageing looks like, researchers can present the algorithm with a brain scan and ask it to predict how old that brain is. This is known as a “brain age”, and it can be different from the individual’s actual chronological age.
Older brain age has been associated with poorer cognitive functioning and higher risk of neurological conditions, such as dementia. And knowing an individual’s brain age could help clinicians predict an individual’s risk of developing these conditions. Previous research has found that cardiometabolic risk factors, such as high blood pressure and diabetes, are associated with higher brain ages (i.e., older-looking brains). Understanding more about how modifiable cardiometabolic risk factors influence brain age could help clinicians create interventions which support brain health.
Dani Beck and his colleagues sought to investigate this question using health information and brain scans from 790 participants. They found that a number of cardiometabolic risk factors were related to older brain age. These risk factors included higher systolic blood pressure, higher pulse rate and higher levels of C-reactive protein, a molecule that has been linked to inflammation in the body. In addition, they found that people with higher systolic blood pressure and higher waist-to-hip ratios showed faster brain ageing over time.
This research suggests that taking steps to improve cardiometabolic health may also help to slow down brain aging, which in turn could reduce vulnerability to dementia and other neurological conditions. Similarly, focusing on keeping cardiometabolic risk as low as possible across the lifespan could help to keep the brain healthy later in life.
