Serious head injuries may lead to faster ageing of the brain, a new study suggests.

UK researchers analysed the brain scans of over 1,700 people, including 99 who had suffered a traumatic brain injury at some point. These injuries were caused by road traffic accidents, falls or assaults.

They found that those with serious head injuries displayed changes in the structure of their brains and these brains were estimated to be around five years older than the person's actual age.

"Your chronological age is not necessarily the best indicator of your health or how much longer you will live. 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," commented lead researcher, Dr James Cole, of Imperial College London.

The study noted that in the brains of the healthy participants, there was no difference between predicted age and real age. However among those with head injuries, there was a major difference, and this difference grew the more severe the injuries.

The researchers also noted that the changes in brain structure among the injured did not necessarily occur during the injury itself, but later on.

"Traumatic brain injury is not a static event. 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," Dr Cole pointed out.

Details of these findings are published in the journal, Annals of Neurology.