Is the likelihood of a football player developing chronic traumatic encephalopathy (CTE) influenced by the number of concussions they receive? The largest CTE study to date, a new study of 631 deceased football players, found that the number of concussion diagnoses alone was not associated with CTE risk. Instead, football players’ chances of developing CTE were linked to the number and severity of their head impacts.
The study was published in Nature Communications by Mass General Brigham, Harvard Medical School, and Boston University (BU) researchers. It estimated the number and severity of head impacts suffered by football players throughout their careers by utilizing an innovative new tool known as a positional exposure matrix (PEM), which combined data from 34 distinct studies.
Senior author Jesse Mez, MD, MS, Associate Professor at the BU Chobanian and Avedisian School of Medicine and Co-Director of Clinical Research at the BU CTE Center, stated, “These results provide added evidence that repeated non-concussive head injuries are a major driver of CTE pathology rather than symptomatic concussions, as the medical and lay literature often suggests.”
“These findings add to the evidence that repeated non-concussive head injuries, rather than symptomatic concussions, are a major cause of CTE pathology,”
Senior author Jesse Mez, MD, MS, Associate Professor at the BU Chobanian .
Researchers say that the new data could help football develop a strategy for preventing CTE in current and future players.
Lead author Dan Daneshvar, MD, Ph.D., Assistant Professor at Harvard Medical School and Physician at Mass General Brigham and Women’s Hospital affiliate Spaulding Rehabilitation, stated, “This study suggests that we could reduce CTE risk through changes to how football players practice and play.” Assuming we cut both the quantity of head influences and the power of those hits by and by and games, we could bring down the chances that competitors foster CTE.”
Based on the levels and positions that athletes played during their football careers, the researchers estimated the cumulative number of head impacts as well as the cumulative linear and rotational accelerations associated with those impacts using the brand-new PEM tool. The football players’ CTE status, CTE severity, and pathologic burden were all correlated with cumulative repetitive head impact (RHI) exposure, according to the study. In addition, the study found that models based solely on the duration of play or the number of hits to the head were less accurate at predicting CTE status and severity than models based solely on the intensity of impacts.
The PEM is a useful tool that can be utilized by researchers to enhance studies on football’s risks. By utilizing the PEM in subsequent studies, researchers can gain a deeper understanding of the specific kinds of RHI that are most likely to result in these issues by investigating additional potential effects of RHI exposure other than CTE.
Daneshvar stated, “Although this study was limited to football players, it also provides insight into the impact characteristics most responsible for CTE pathology outside of football.” “Your brain doesn’t care what hits it.” The association between football players’ estimated lifetime force and CTE probably holds true for other contact sports, military service, or domestic violence.”
The study’s use of a convenience sample of football-playing brain donors, who tended to be more exposed to RHI than the general football player population, is a limitation. However, the findings can still be applied to the majority of football players because a significant number of donors had lower exposures.
More information: Daniel H. Daneshvar et al, Leveraging football accelerometer data to quantify associations between repetitive head impacts and chronic traumatic encephalopathy in males, Nature Communications (2023). DOI: 10.1038/s41467-023-39183-0
