The long-term effects of concussions and other brain trauma has been a big focus in recent years thanks in large part to the NFL and many of its former players. The league has been forced to address concerns that it doesn’t do enough to prevent concussions and sideline players who are suspected of sustaining them, but there’s still a long way to go. Now, new research suggests that just one concussion can be enough to increase the risk of developing Parkinson’s disease later in life.
The research, which was published in the journal Neurology, used data from the Veterans Health Administration to compare reports of traumatic brain injury (TBI) with the emergence of Parkinson’s symptoms later in life. What they found was a dramatic increase in the number of Parkinson’s patients who had reported some form of TBI, including very mild TBI (mTBI) from concussions, earlier in their lives.
“Among military veterans, mTBI is associated with 56% increased risk of [Parkinson’s Disease], even after adjusting for demographics and medical/psychiatric comorbidities,” the researchers write. “This study highlights the importance of TBI prevention, long-term follow-up of TBI-exposed veterans, and the need to determine mechanisms and modifiable risk factors for post-TBI PD.”
While the study focused on military veterans, it has implications that stretch much wider than the armed forces. Tens of millions of people are diagnosed with concussions every year, and we’ll never know how many go undiagnosed.
Overall, the risk of developing Parkinsons is still rather low, even with a past that includes a traumatic brain injury. Less than one percent of veterans in the study developed Parkinson’s. Those who did experience a concussion or other TBI demonstrated a significantly higher chance of being diagnosed with it, when compared with the baseline, but the total number of Parkinson’s suffers is only slightly higher in those with TBI.
Nevertheless, it’s worth considering how repeated concussions over the course of a lifetime in team sports such as football could affect an individual later in life. Retired NFL players have admitted to playing through more concussions than they’d like to admit, and repeated mTBI is already linked to CTE. It should be pretty obvious that knocking your brain around is bad news, but we might only be seeing the start of the true cost of concussions.