Serious head injuries may lead to premature brain aging, a new British study suggests.

"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," study leader Dr. James Cole, from Imperial College London, said in a college news release.

Researchers looked at brain scans from 99 people who suffered traumatic brain injuries from traffic crashes, falls or assaults.

After their injuries, they had persistent neurological problems. Their brain scans were taken between one month and 46 years after their injuries, according to the researchers. These scans were compared to brain scans of healthy people.

The researchers also created a computer model using measures of the brain's white matter and gray matter to estimate a person's brain age.

They said it's known that head injuries increase the risk of age-related brain conditions, such as dementia. The computer model would serve as a screening tool to identify brain injury patients at risk of developing problems.

The study found that the brains of the people with head injuries showed changes in structure that resembled those in older people.

On average, their brains appeared to be about five years older than their actual age, estimated using the computer model.

The study appears in the April issue of the Annals of Neurology.

The brain age prediction model might also be used to screen seemingly healthy people.

"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," Cole said.