Skip to main content

September 24, 2024

Study of Former NFL Players Finds 1 in 3 Believe They Have CTE

Those with concerns also report higher rates of suicidality, treatable conditions that mimic CTE cognitive symptoms.

At a glance:

  • New study of nearly 2,000 former NFL players found that 34 percent think they have CTE, a condition it is not yet possible to confirm in a living person.
  • Former players who believed they had CTE reported significantly more cognitive problems, depression, suicidality, chronic pain, and other problems than those who did not have concerns.
  • To reduce chances of players prematurely attributing symptoms to CTE, which may lead to hopelessness and thoughts of self-harm, authors recommend identifying and treating any conditions that cause similar neurocognitive symptoms.

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 postmortem exam of the brain.

The study — conducted by a team including researchers from Harvard Medical School, Harvard T.H. Chan School of Public Health, Massachusetts General Hospital, Brigham and Women’s Hospital, and Spaulding Rehabilitation Hospital who are part of the Football Players Health Study at Harvard University — is published Sept. 23 in JAMA Neurology.

According to the study, players who believed they had CTE reported significantly more cognitive problems and a higher proportion of low testosterone, depression, mood instability, headaches, chronic pain, and head injury 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 that such symptoms could be independent of CTE, the authors said.

Neurocognitive symptoms may arise from a variety of causes not related to CTE, and the researchers warned that all such symptoms need to be taken seriously by clinicians. These include neurodegenerative changes in the brain that should be considered and ruled out through neurocognitive assessments, including physical exams, MRI, and CT scans, they said.

The researchers also cautioned that players with neurological symptoms and suicidality may indeed be eventually diagnosed with CTE, but that can only be learned through a postmortem 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 principal investigator of the Football Players Health Study.

“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,” Zafonte said. “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.”

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 believed they have CTE.

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, the authors said.

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 are common to former NFL players such as sleep apnea, low testosterone, high blood pressure and chronic pain, which can be associated with problems in thinking, memory and concentration,” said first author Rachel Grashow of Harvard Chan School and the Football Players Health Study.

“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. However, 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, HMS associate professor of medicine at Mass General, professor of medicine at the University of Lausanne in Switzerland and 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.

 

Adapted from a Mass General Brigham news release.


Authorship, funding, disclosures

Additional authors include Grant L. Iverson, Douglas P. Terry, Heather DiGregorio, Inana Dairi, Cheyenne Brown, Paula S. Atkeson, Alicia J. Whittington, LeRoy Reese, Jonathan H. Kim, Niki Konstantinides, Herman A. Taylor, Frank E. Speizer, Daniel H. Daneshvar, and Marc G. Weisskopf.

The Football Players Health Study is supported by the National Football League Players Association (NFLPA). The NFLPA did not contribute to the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

This work received support from Harvard Catalyst | The Harvard Clinical and Translational Science Center (National Center for Advancing Translational Sciences, NIH, Award UM1TR004408) and financial contributions from Harvard University and its affiliated academic health care centers. The content is solely the responsibility of the authors and does not necessarily represent the official views of Harvard Catalyst, Harvard University and its affiliated academic health care centers, or the National Institutes of Health.

Baggish has received funding from the National Institutes of Health/National Heart, Lung, and Blood Institute, the NFLPA, and the American Heart Association and receives compensation for his role as team cardiologist from the U.S. Olympic Committee/U.S. Olympic Training Centers, U.S. Soccer, U.S. Rowing, the New England Patriots, the Boston Bruins, the New England Revolution, and Harvard University. Zafonte reported receiving royalties from Springer/Demos publishing for serving as coeditor of the text Brain Injury Medicine; serving on the scientific advisory board of Myomo Inc. and onecare.ai Inc.; evaluating patients in the Mass General Brain and Body–TRUST Program, which is funded by the NFLPA; and receiving grants from the NIH. Grashow received grant funding from the NFLPA. Additional author disclosures can be found in the paper.

TOPICS
Study News
Media Coverage