Early life concussions linked to later cognitive decline

Twin study links brain injury to cognitive decline in older veterans.


This study looks at what can happen in the future to people who had bumps on their heads when they were kids. These bumps, called concussions, can hurt the brain and cause problems even in old age.

Twins study finds that getting a concussion at a young age can lead to lower scores on memory and thinking tests later in life. It also shows that those with concussions experience a faster decline in these scores than those without head injuries. The study was published in the September 6, 2023, online edition of Neurology, the American Academy of Neurology medical journal.

Study author Marianne Chanti-Ketterl, Ph.D., MSPH, of Duke University in Durham, North Carolina, said, “These findings indicate that even people with traumatic brain injuries in earlier life who appear to have fully recovered from them may still be at increased risk of cognitive problems and dementia later in life. Among identical twins, who share the same genes and many of the same exposures early in life, we found that the twin with a concussion had lower test scores and faster decline than their twin who had never had a concussion.”

This study looked at 8,662 men who were veterans of World War II. They took a thinking test when they were around 67 years old and retook it thrice over the next 12 years. The average score on the test was 32.5 out of 50. Approximately 25% of these men had a concussion at some point.

The study found that twins who had concussions tended to have lower scores on the thinking test when they were 70, especially if they had a concussion where they passed out or if they were older than 24 when it happened. Twins who had more than one concussion or had concussions after age 24 also had a faster decline in their thinking skills.

For example, a twin with a concussion after age 24 scored 0.59 points lower on the test at age 70 than his twin who didn’t. His thinking skills also declined faster, dropping by 0.05 points every year.

These findings considered other things affecting thinking skills, like high blood pressure, alcohol use, smoking, and education.

Even though the impact of traumatic brain injury on thinking skills is small, it’s still important to pay attention to it. The study suggests that when someone has a concussion, mainly due to sports or military service, it might be a good idea to check their thinking skills as they age. This way, we can provide early help to slow down memory problems or prevent dementia.

One thing to note is that the study relied on participants’ reports of their brain injuries, so not all damages may have been remembered or reported correctly. The study received support from the National Institute on Aging and the U.S. Department of Defense.

In conclusion, this study shows that when kids or teenagers get concussions, they might have a higher chance of having memory and thinking problems when they get older. It emphasizes the need for continued research to understand the long-term effects of head injuries better and develop strategies for mitigating cognitive decline among affected individuals.

Journal Reference:

  1. Marianne Chanti-Ketterl, Carl F Pieper et al., Associations Between Traumatic Brain Injury and Cognitive Decline Among Older Veteran Men – A Twin Study. Neurology. DOI: 10.1212/WNL.0000000000207819.


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