Early traumatic brain injuries may raise the chance of late-life cognitive impairment in some people

According to a study of twins, having a concussion as a child is associated with lower results on tests of thinking and memory decades later as well as a more accelerated decline in those scores than twins without a concussion or other traumatic brain injury (TBI). The research is published online in Neurology, the medical journal of the American Academy of Neurology, on September 6, 2023.

8,662 men who had served in World War II participated in the study. At the beginning of the study, when they were an average of 67 years old, the participants underwent a thinking skills exam. They subsequently repeated it up to three more times over a 12-year period. The test has a scoring range of 0 to 50. At the start of the trial, each participant received an average score of 32.5 points.

Twenty-five percent of the participants had ever had a concussion.

Particularly if they had a concussion when they lost consciousness or were older than 24 when they had their concussion, twins who had experienced a concussion were more likely to have poorer test scores at age 70. In comparison to twins without a history of traumatic brain injury, individuals with traumatic brain injury with loss of consciousness, multiple traumatic brain injuries, and injuries sustained beyond the age of 24 were more likely to experience a higher rate of cognitive decline.

For instance, a twin who sustained a traumatic brain damage after the age of 24 scored 0.59 points worse at age 70 than his twin who had not. His cognitive abilities also deteriorated more quickly, by 0.05 points year.

Other variables that may have an impact on thinking abilities, such as high blood pressure, alcohol usage, smoking status, and education, were taken into account in these findings.

“Although these effect sizes are modest, the contribution of TBI on late life cognition, in addition to numerous other factors with a detrimental effect on cognition, may be enough to trigger an evaluation for cognitive impairment,” Chanti-Ketterl said. “With the trend we are seeing with increased emergency room visits due to sports or recreation activity injuries, combined with the estimated half million members of the military who suffered a TBI between 2000 and 2020, the potential long-term impact of TBI cannot be overlooked. These results may help us identify people who may benefit from early interventions that may slow cognitive decline or potentially delay or prevent dementia.”

The fact that participants in the study reported their traumatic brain injuries poses a drawback to the study because not all traumas may have been remembered or accurately reported.

The National Institute on Ageing and the US Department of Defence provided funding for the study.