Chronic Traumatic Encephalopathy (CTE) is a cause for concern for many athletes and veterans, as it is a degenerative brain disease that causes serious cognitive, mood, and behavior problems. Researchers of a new study found that even without concussions, repeated head injuries triggers CTE.

Head Hitting, Not Concussion Causes CTE

CTE has caused serious problems among athletes, veterans, and others who have experienced head trauma. In the past, concussions were seen to be the major cause of CTE, but a new study suggests that hits to the head triggers CTE, not concussions. This is perhaps why a significant 20 percent of athletes who exhibited signs of CTE did not have a history of having a concussion.

Results of the new study show that when head injuries or "hits" happen, the blood vessels leak proteins to the brain and its adjacent tissues, causing them to be inflamed. As it happens, CTE is characterized by the accumulation of tau proteins around the blood vessels.

Abnormal Protein Accumulation

Researchers collected data by studying the brains of four deceased teenage athletes who suffered head injuries days before their deaths and the brains of four other young athletes who did not suffer head trauma shortly before their deaths.

The brains of the athletes who had head injury shortly before death revealed that one of them had early signs of CTE, while two had abnormal tau protein accumulation, which was marked by brown stains in parts of the brain. On the other hand, the brains of those who did not have a head injury shortly before death did not have the same pathologies.

Mice Study

To test their hypothesis, researchers conducted an experiment wherein mice were exposed to either blast exposure or repeated head impacts. Upon scanning the mice's brains, researchers found leakage in the blood vessels of the mice consistent with that of the teenagers with head injuries. What's more, they found strong evidence linking head injuries to early CTE that is unrelated or independent of concussion.

"We were surprised that the brain pathology was unrelated to signs of concussion," said Lee Goldstein, coauthor of the study. He also adds that the disruption of capillaries in the brain result in the protein leakage into the brain.

CTE Prevention

CTE is quite like a silent killer, as symptoms often appear years after a head injury. It causes cognitive, mood, and behavioral symptoms and happens when tau proteins spread throughout the brain and eventually kills the brain cells. According to researchers, in order to fully address and reduce the risk of CTE among athletes and veterans, a reduction of head impacts is needed, as focusing on concussions does not particularly address the root of the problem.

The study is published in the journal Brain.