A NEUROSURGEON has warned of long-term effects caused when people experience mild concussion. They are at increased risk of a second injury, may suffer ongoing or later impairment of the brain, and are at increased risk of later dementia.
Prof Douglas Smith is the director of the Centre for Brain Injury and Repair and professor of neurosurgery at the University of Pennsylvania School of Medicine. He spoke at a session on brain injury at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Diego.
Concussion is generally ignored as a health issue, but it can cause significant long-term effects. The issue “needs more attention”, he suggests. “Experiencing one traumatic brain injury is a risk factor for having a second injury.” It also increases a person’s risk of developing Alzheimer’s disease.
The issue of concussion and brain injury has made headlines in recent years, with researchers discovering that many American football players suffered long-term cognitive impairment, akin to that seen in a boxer, without ever experiencing a head injury.
The issue has relevance for anyone involved in sports that involve heavy collisions, such as rugby and to a lesser extent GAA.
The injuries caused by concussion were “not inconsequential”, he states. The fact that damage can be detected after concussion meant there should be “much more extensive efforts to prevent, diagnose and treat” the injury.
Dr Smith does not hesitate when asked about the implications after experiencing a concussion. “They should not put their head at risk again, ever,” he says. “We do believe you have a lowered threshold for injury after concussion. We don’t know the long-term effects.”
Some patients do not seem to be affected by concussion. Others suffer from persisting neurological and cognitive problems that can go on for months and longer. “We are trying to discover what makes the difference between these two groups,” he says.
His research team has funding from the US National Institutes of Health to try and identify those patients at greater risk of cognitive impairment.
He is also trying to develop a way to confirm whether a person has experienced a concussion, and is not suffering from more significant brain injury. “I want to find a therapeutic target for concussion,” he says.
He is involved in research to understand what happens in the brain to cause the disorientation and confusion, among other symptoms, often seen after concussion. Human and animal studies are looking at the brain two to four days after injury, using advanced neuroimaging techniques.
These have already identified distinct changes throughout the white matter in the brain. Concussion usually involves a violent movement of the head, causing the brain momentarily to compress. This causes stretching and sometimes breakage of axons, the long nerve fibres that electrically connect nerve cells.
The researchers have yet to learn what happens in the weeks and months after a concussion – whether the axons repair themselves or remain damaged. “I suspect there is a repair mechanism,” Prof Smith said. Learning how it worked would provide a wealth of information about what happens during concussion.