The latest CTE study needs to be put in context
By Ben Volin, Boston Globe
The latest CTE study made big headlines when it was released this past week.
And for many of those in the medical and football communities, the headlines are a problem.
The study, conducted by Dr. Ann McKee of Boston University and published on Tuesday in the Journal of the American Medical Association, proclaimed that 110 of the 111 brains of deceased NFL players that it studied were found to have the degenerative brain disease chronic traumatic encephalopathy.
The findings were trumpeted in the Globe and several national media outlets, replete with startling pictures of brain fragments of the deceased players.
The implication of the study was obvious — football causes brain injuries, and brain injuries lead to CTE, which leads to a host of mental problems. Ravens offensive lineman John Urschel, a PhD candidate at MIT, retired from football last week following the report’s release.
While few debate the dangers of football as it relates to head injuries, some in the medical community take issue with the report’s alarmist tone. McKee’s study certainly shows that CTE is an issue that demands more research, but it did little to advance the overall knowledge surrounding CTE.
“Concussion research is still in its infancy,” wrote former Chargers team doctor David Chao last week, in a piece entitled, “Plea for timely truth about football’s link to brain disease.” “One day we hope to have precise classifications for the types of head injury. For example, the outcome of a ‘Grade 2B occipital lobe concussion’ or a ‘Grade 3C temporal lobe concussion’ might have different treatment and prognosis. It is hard to find a cure when you don’t know the exact disease. The truth is our knowledge of head injury today is like that of knee injuries in the pre-MRI and arthroscopy era. Everything was a knee sprain and we didn’t differentiate between ACL, PCL, MCL, LCL, or medial versus lateral meniscus tears.”
The BU study was a “convenience sample” of 202 brains donated by families of former football players who demonstrated cognitive issues in life. Since there is still no way of diagnosing CTE in living people, no meaningful testing has occurred to determine the true causes of CTE and the role of football and other sports.
We don’t know whether CTE is hereditary or caused by outside factors such as alcoholism or chemical dependence. And we don’t know why some people afflicted with CTE die young and others make it to old age.
“That first step is not solved yet — whether there’s a definitive link to concussions,” Dr. Lili-Naz Hazrati, a Toronto neuropathologist, told the Toronto Sun last week. “So how can you even think about who’s the most susceptible? Who’s not? What age is the worst? Just looking at these brains [posthumously], you cannot say any of that. It’s just impossible at this point.”
McKee, the chief of neuropathology at the VA Boston Healthcare System and director of the CTE Center at Boston University, acknowledged the limitations of her study.
“There’s a tremendous selection bias,” she told the New York Times, noting that many brains were donated specifically because the former player showed troubling symptoms.
But that point was seemingly glossed over last week. The “99 percent” and “110 out of 111” are what got people’s attention.
The same JAMA medical journal published a study on July 3 stating that men who played high school football in Wisconsin in 1957 were at no increased risk of later-life cognitive impairment or depression.
That study barely registered with the media, as attacking football seems to be far more fashionable than defending it.
The NFL has gotten a lot of criticism about denying the link between concussions and CTE, and much of it is deserved. Late last week, ESPN reported that the NFL is walking away from a partnership with the National Institutes of Health to study concussions, after giving less than half of a $30 million gift that it announced back in 2012. NIH officials criticized the NFL for being too heavy-handed in directing where the money went and refusing to allow BU researcher Dr. Robert Stern to lead one of the studies.
But the motivations of some of the top concussion researchers are also questionable, as they fight each other for funding, access to brains, and publicity.
“Competing scientists should not be fighting to sign up brains for when someone passes,” Chao wrote. “We should be studying these people while they are alive and trying to offer help and support.”
The NFL needs to continue to do more to support concussion and CTE research and remain vigilant in protecting its players. But researchers also need to be a little more honest with the public about the context of their findings and how little we still know about brain injuries.
Patriots special teams captain Matthew Slater may have summed it up the best last week as he began his 10th training camp.
“As a player, you’re definitely thankful that they’re starting to look into that, do the necessary research, and hopefully get us to a better place when it comes to that,” he said of the CTE study. “Being married to a pathologist, I know that there is a lot I don’t know and there is a lot that we still have yet to learn.”