A new study found that older adults, aged 55 and above, are at higher risk of developing dementia after enduring a traumatic brain injury (TBI). 

Researchers from the University of California, San Francisco looked at the data of 164,661 people who were brought to the hospital due to TBI and non-TBI body trauma or fractures excluding the head and neck. About 32 percent (or 51,799 patients) were identified to have a TBI.

The focus of the study was directed towards the 32 percent who had suffered traumatic brain injuries. The findings showed that 8.4 percent of those with a TBI developed dementia compared to a lesser 6 percent of the non-TBI patients. Though not significantly different, those who suffered from brain injuries were diagnosed with the memory disorder in an average of 3.1 years after the injury, compared to 3.3 years for those who had non-brain trauma.

"This was surprising and suggests that the older brain may be especially vulnerable to traumatic brain injury, regardless of the traumatic brain injury severity," study lead author Dr. Raquel Gardner, a clinical research fellow with San Francisco Veterans Affairs Medical Center, said to Healthday News.

The team concluded that one incident of brain injury increases one's risk of developing dementia by 26 percent; more than one doubles the risk. However, some experts were not convinced of the findings because of the data used in the study.

"There was not a non trauma control group included, which may have answered the question of whether NTT (i.e. body trauma itself) raised the risk of dementia significantly above age-equivalent controls without non brain trauma (perhaps from inflammation or other complications)," Dr. Steven T. DeKosky of the University of Pittsburgh School of Medicine, said in an editorial.

The study authors clarified that there could be other factors that may have contributed to the increased risk, such as genetics, other illnesses, environment and other injuries. Gardner also added that further research is needed to establish a link between the two.

"I hope that these results will highlight the critical importance of preventing falls in older adults," Gardner said.

Further details of the study were published in the Oct. 27 issue of JAMA Neurology.