A mild concussion can raise your risk of developing Parkinson’s disease by 56 percent, according to new research.
The study, led by Raquel Gardner, assistant professor of neurology UC San Francisco, supports earlier theories that some professional athletes have developed the degenerative disease due to their sports careers.
That includes boxer Muhammad Ali.
Gardner’s team analyzed data on more than 300,000 veterans from three U.S. Veterans Health Administration databases. Half of the subjects had endured a traumatic brain injury (TBI) during their lives that ranged from mild to moderate to severe. The other half of the subjects had not experienced a TBI.
Veterans ranged in age from aged 3 to 65, and were followed for up to 12 years. At the start of the study, no subjects had Parkinson’s, which causes gradual degeneration of nerve cells in the part of the brain that controls body movement.
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Over the course of the research, 1,500 were eventually diagnosed with the disease. Of those, 949 had previously had a traumatic brain injury.
“Even in this study, the vast majority of veterans with traumatic brain injury did not develop Parkinson’s,” Gardner said, adding that the study helps connect the dots between head injury and Parkinson’s.
The researcher added that traumatic brain injuries could cause abnormal proteins to accumulate in the brain. It's also possible that a brain injury might make the brain less resilient to aging.
The average person has a just 1-2% chance of developing Parkinson’s.