As a parent, it wouldn't have taken much evidence for me to decide to keep my two (now grown) children out of high-impact sports like football and soccer. But as a scientist and a physician, I have a different perspective. I can see how much we still don't know much about the impact of childhood sports participation and concussions on later-life brain health.
When it comes to adult brain injury and dementia risks, the evidence is more established. Last year, the NFL stated in federal court documents that it expects nearly a third of its retired players to develop long-term cognitive problems and predicted that the conditions are likely to emerge at "notably younger ages" than in the general population.
Recently, 49ers inside linebacker Chris Borland announced his early retirement from the NFL after just one season. Borland had the benefit of stronger research on the link between adult concussions and dementia risk. "The decision was simple after I had done a lot of research and it was personal," Borland said. "I was concerned about neurological diseases down the road if I continued to play football."
My life's work is ending Alzheimer's disease and related dementias, the very things that Borland feared developing in his later life. I am deeply committed to strengthening our scientific understanding of the causes of dementia, including untangling the impact of sports-related childhood concussions on later-life cognitive function.
This month, I co-authored a consensus statement published in Nature Reviews Neurology (PDF) about the need to advance research into the short- and long-term neuropsychological outcomes of youth sports-related concussions. The statement was the result of a meeting convened by Safe Kids Worldwide, the Alzheimer's Drug Discovery Foundation, and the Andrews Institute for Orthopaedics and Sports Medicine. The meeting brought together more than 25 experts in a variety of fields including neurology, sports injury reporting, ethics, genetics, biomarkers, dementia, and neuroimaging. The group concluded that there is not enough evidence to establish a clear link between early-life repetitive head impacts and adult cognitive decline and dementia.
In the statement, we asserted the need to improve our understanding of the fundamental biology of concussions and how factors like age, sex, and genetics influence concussion susceptibility and recovery. We also called for continued research and development of brain imaging techniques that shed light on the pathology of pediatric brain injury and may accelerate the development of novel therapies. We also noted the importance of improving local and nationwide injury monitoring, eventually tracking the health of young athletes from the beginning of their athletic careers. According to the CDC, there were 250,000 nonfatal traumatic brain injuries recorded among people under the age of 19 in 2009, constituting 65 percent of all sports-related concussions. Many more may have incurred undiagnosed concussions and could suffer consequences in the future. With better monitoring we could improve our understanding of the scope of the problem.
The bottom line: we need to establish and encourage clear lines of research in many different but complementary fields to improve our knowledge and translate that data into actionable guidelines. With more research, we can ensure that parents, coaches, policymakers, and physicians have the information they need to protect the long-term health of young athletes.
Howard Fillit, MD is the Founding Executive Director and Chief Science Officer at the ADDF.