Mild traumatic brain injuries can significantly raise the risk of developing Parkinson’s disease later in life. According to a new study published in April, people who suffer a mild head injury are 56 percent more likely to develop Parkinson’s disease than those who have not experienced an altered state of consciousness, have never been knocked out, or have not had amnesia for up to 24 hours. The chances of developing Parkinson’s disease rise with the severity of the head injury. Individuals who suffered moderate to severe brain injury face an 83% increased risk.
The research looked at data collected from 325,870 U.S military veterans ranging from 31 to 65 years. Half of the participants had suffered mild, moderate or severe brain injury, and half hadn’t. While all the participants had served in the military, most of those diagnosed with Parkinson’s actually got their head injuries during civilian activities.
The Link Between Head Injuries and Parkinson’s
It’s not clear exactly how the increased risk of Parkinson’s is linked to head injuries. But studies have found abnormal deposits of a protein called alpha-synuclein in people with brain injuries. Also, head injuries, including mild ones, can cause inflammation in the brain, which may result in changes in brain structures and cells that contribute to Parkinson’s. Previous studies have linked head trauma as being a risk factor for neurodegenerative disorders and this new study reinforces that evidence.
None of the vets had a diagnosis of Parkinson’s when the study commenced but during follow-up time, from October 2002 to September 2014, 1,462 participants were diagnosed with the disease. One in 212 had suffered a mild traumatic brain injury, and one in 134 reported suffering head trauma that was moderate to severe. While the study looked at veterans, the results may have important inferences for those in sports and the general public as well. Concussions are commonly suffered by people serving in the military, on the sports field, or those involved in motor vehicle crashes.
Parkinson’s is the second-most common neurodegenerative disease in America. It leads to problems with balance and movement. Individuals often develop very slow, stiff movements, tremors, bradykinesia, rigidity, and loss of postural reflexes, which develop gradually and eventually result in difficulty completing simple tasks.