A new study of nearly 2,000 former NFL players shows that about one-third believe they have chronic traumatic encephalopathy (CTE), a neuropathological condition linked to repeated head trauma that can only be diagnosed through a post-mortem exam of the brain.
- LIANA WAIT | Mass General Brigham Communications
The study, which was conducted by a team including researchers from Harvard Medical School and the Harvard T.H. Chan School of Public Health at Massachusetts General Hospital, Brigham and Women's Hospital, and Spaulding Rehabilitation Hospital who are part of the Football Players Health Study at Harvard University, was published Sept. 23 in JAMA Neurology.
According to the study authors, players who believed they had CTE reported significantly more cognitive problems and a higher proportion of low testosterone, depression, headaches, and chronic pain, compared with those who did not have concerns about CTE. These conditions and others have been shown to cause cognitive problems even in those without head injury, indicating such symptoms could be independent of CTE.
Because neurocognitive symptoms may arise from a variety of causes not related to CTE, the researchers warn that all neurocognitive symptoms need to be taken seriously by clinicians. These include neurodegenerative changes in the brain, considered and ruled out through neurocognitive assessments, including physical exams, MRI, and CT scans.
The researchers also caution that players with neurological symptoms and suicidality may indeed be eventually diagnosed with CTE, but that can only be learned through a post-mortem exam.
"As complex human beings, our beliefs can exert a strong impact on our health," said coauthor Ross Zafonte, the Earle P. and Ida S. Charlton Professor of Physical Medicine and Rehabilitation at HMS and president of Spaulding Rehabilitation Network. Zafonte is also the principal investigator of the Football Players Health Study at Harvard University.
"The symptoms that raise CTE concerns are real and CTE concerns are valid, but it's critical to understand that having persistent fears about this condition can take a toll on mental health. When these concerns discourage former NFL players from receiving effective treatments for other or interrelated conditions related to physical and emotional health, it's our responsibility to intervene," Zafonte said.
Receiving a diagnosis of incurable neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's disease are associated with elevated suicide risk. To investigate whether the perception of CTE shows similar associations with suicidality, the researchers surveyed 1,980 former professional football players. They wanted to find out what proportion believe they have CTE, which player characteristics were commonly associated with this belief, and whether CTE concerns were associated with frequent thoughts of suicide or self-harm.
The analysis showed that 34 percent of players believe that they have CTE. Participants who expressed concerns about CTE were more likely to report low testosterone, depression, mood instability, pain, cognitive symptoms, and head injury.
Approximately 25 percent of participants who believed they had CTE also reported suicidality compared with 5 percent of participants who did not believe they had CTE. In analyses that accounted for the influence of depressive symptoms on suicidality, those who believed they had CTE were still twice as likely to report frequent thoughts of suicide or self-harm, even if they reported similar levels of depression. This finding suggests that some suicidality may stem from the assumption that a former player has an untreatable neurodegenerative disease rather than from depression.
While concerns about CTE are legitimate, treating comorbid conditions may alleviate symptoms and improve overall mood, the researchers said.
"A key takeaway from this study is that many conditions common to former NFL players such as sleep apnea, low testosterone, high blood pressure, and chronic pain can cause problems with thinking, memory, and concentration," said first author Rachel Grashow of the Harvard Chan School.
"While we wait for advances in CTE research to better address living players' experiences, it is imperative that we identify conditions that are treatable. These efforts may reduce the chances that players will prematurely attribute symptoms to CTE, which may lead to hopelessness and thoughts of self-harm," Grashow said.
Since CTE can currently only be diagnosed by autopsy, the researchers cannot rule out the possibility that some of the players who reported concerns do, in fact, have CTE-related brain changes, but they say that it's important for former players and their clinicians to focus on the things that can be treated.
"Until clinical guidelines and treatments for CTE become available, former players and their physicians should explore treatment interventions and positive health behavior changes that have been shown to improve cognitive function, overall health, and quality of life," said senior author Aaron Baggish, a professor of Medicine at the University of Lausanne in Switzerland and a senior faculty member of the Football Players Health Study.
"Interventions including weight loss, exercise, improving sleep and implementing a low-salt diet may improve cognitive function," Baggish noted.
