Serious brain injuries cause changes in the brain similar to those observed in older individuals, according to new findings from researchers at Imperial College London.
According to the report published in Annals of Neurology, the researchers evaluated brain scans from over 1,500 healthy people to develop a computer program capable of predicting a person’s age from the brain scan. The, the team used the program to estimate the “brain age” of 113 more healthy participants and 99 patients with traumatic brain injury.
On average, the brain injury participants were estimated to be approximately 5 years older than their real age.
“Your chronological age is not necessarily the best indicator of your health or how much longer you will live,” said Dr James Cole, who led the study, from the Department of Medicine at Imperial College London. “There is a lot of interest in finding biomarkers of ageing that can be used to measure a certain aspect of your health and predict future problems.”
The program developed for the study used magnetic resonance imaging scans to assess differences in the volume of white and grey matter in different parts of the brain. The 99 participants with brain injury included people who had experienced road accidents, falls, or assaults, and had persistent neurological problems.
Scans were taken between one month and 46 years after injuries.
The program was shown to be highly accurate among healthy participants, showing a difference between predicted age and actual age of zero. The TBI patients however showed significant differences between “brain age” and their actual age, with larger discrepancies in more severely injured individuals. The largest differences between predicted and actual age were linked with cognitive impairments such as poor memory and slow reaction time.
The researchers also found a correlation between the amount of time that had passed since the injury and difference in predicted age, which suggests these changes occur over time as the result from ongoing biological processes.
“Traumatic brain injury is not a static event,” said Dr Cole. “It can set off secondary processes, possibly related to inflammation, that can cause more damage in the brain for years afterwards, and may contribute to the development of Alzheimer’s or other forms of dementia.”
“We want to do a study where we use the program to estimate brain age in healthy people, then see if the ones with ‘old brains’ are more likely to get neurodegenerative diseases. If it works, we could use it to identify people at high risk, enroll them in trials and potentially prescribe treatments that might stave off disease,” said Dr Cole.