Submitted by: Marcos A. Abreu*(1), Fred J. Cromartie (1), Brandon D. Spradley (1)
(1) United States Sports Academy
United States Sports Academy
One Academy Drive
Daphne, Alabama 36526
Marcos Abreu is a doctoral student at the United States Sports Academy studying sports management.
Purpose: Our understanding of Chronic Traumatic Encephalopathy (CTE) has rapidly advanced, since 2002, when Dr. Bennet I. Omalu first discovered CTE in the brain of deceased former National Football League (NFL) player Mike Webster. Although it is clear that there is a link between the neurological diseases and exposure to repeated mild traumatic brain injuries, the explicit link between the long-term consequences that are associated with CTE and the suicide death of several former NFL players is much less clear. The purpose of this paper is to examine if the psychological and cognitive consequences that are associated with CTE are factors in the suicide death of several former NFL players.
Method: The literature used in this paper was acquired using the words NFL concussions, NFL player CTE research, CTE symptoms in NFL players, and NFL player suicide death in the EBSCOhost and Internet Explorer search engines.
Results: Although similar studies on the relationship between CTE and suicide in former NFL players determined that further research was needed to prove a connection (47, 22), the case study research and testimonial evidence discussed in this study reinforces Omula et al. (2010) findings that identified these psychological and cognitive consequences as key variables associated in suicide death of an alarming amount of NFL players, such as former Eagles and Arizona Cardinals Defensive Back Andre Waters, who resorted to suicide as a result of diminished neurological capabilities and accumulation of symptoms.
Although there is adequate case study research and testimonial evidence to conclude that there is a strong causal relationship between the presence of CTE and suicide in former NFL players as a result of their diminished psychological and cognitive capabilities, to establish a clearer connection, additional research should determine the extent to which the psychological and cognitive consequences are possible variables associated with former NFL player suicide. The challenge is no longer the acceptance of CTE as a diagnosis associated with former NFL players who committed suicide, but rather an account of the symptoms reported with exposure to identical repetitive head traumas before death, for former and current NFL players and other athletes in collision sports.
Application to Sport: Besides providing readers with the current research evidence on CTE, this study sheds light on testimonial evidence that has not been recorded or used for CTE research purposes. Since the research on suicides in former NFL players is still in its infancy, the sports community should place extreme importance on sharing and discussing all of the current literature available. Sharing information will not only help expand discussion that helps others in the sports industry realize the seriousness of the subject at hand, it will also help to emphasize the importance of expanding research efforts.
Keywords: Former NFL Player suicides, Chronic Traumatic Encephalopathy (CTE), Traumatic Brain Injury (TBI)
The culture of the NFL holds in the highest regard a player’s toughness and ability to overcome adversity. These characteristics are respected within the football culture so much that coaches clarify the importance of these characteristics at all levels of football. As a result, in recent years, former NFL players brought several lawsuits against the league, claiming monetary damages for negligence. At issue for football players, was whether the NFL was aware that repeated concussions can add up to psychological consequences, in addition to other health difficulties. In particular, there was a concern about the neurodegenerative disease Chronic Traumatic Encephalopathy (CTE).
Published research in the American Family Physician identified concussions as “a disturbance in brain function caused by direct or indirect force to the head. It is a functional rather than structural injury that results from shear stress to brain tissue caused by rotational or angular forces—direct impact to the head is not required (37).” Usually, a concussion may involve physical (e.g., headaches, nausea), cognitive (e.g., difficulty with concentration or memory), emotional (e.g., irritability, sadness), and ‘maintenance’ (e.g., sleep disturbances, changes in appetite or energy levels) symptoms (39).
Based solely on surveys, in 2000, director of the Brain Injury Program at Burke Rehabilitation Hospital, Barry Jordan and Dr. Julian Bailes suggested that the concussions suffered by NFL players may lead to neurological problems, later on in life (1). Later, Dr. Kevin Guskiewicz and his contemporaries suggested that retired NFL players who sustained 3 or more concussions had a higher rate of mild cognitive impairment diagnosis (18) and an increased threat of clinical depression (19). The research further emphasized the importance of understanding the potential neurological consequences associated with repeated concussion.
Currently, the data from FRONTLINE’s Concussion Watch project, which has been tracking the head injuries from the NFL injury report, reported 171 concussions in 2012, 152 concussions in 2013, 123 concussions in 2014, and 67 concussions thus far in 2015 (16). Although the NFL injury report has shown a decrease in concussions since 2012, in 2014, FRONTLINE reported that one-third of all concussions are left off the injury report and half the time injured players come back without missing a game, and some positions (receivers and cornerbacks) acquire more concussions than others (6).
Although it is clear that concussions are dangerous and should be taken seriously, the growing number of suicide deaths and CTE diagnosis of several former NFL football players has stirred a debate over whether or not repetitive traumatic brain injury (TBI) in contact sports such as football can produce the psychological consequences (behavioral/mood changes) that could lead to suicide later on in life. The purpose of this paper is to examine if the psychological and cognitive consequences that are associated with CTE are factors in the suicide death of several former NFL players.
REVIEW OF LITERATURE
The American Medical Society for Sports Medicine described CTE as “a neurodegenerative disease associated with repetitive brain trauma and characterized pathologically by the accumulation of protein in specific areas of the brain (21).” The protein that collects in specific areas of the brain is called “tau”. According to the National Institutes of Health (2013), “tau is a normal brain protein that folds into tangled masses in the brain cells of patients with Alzheimer’s disease and a number of other progressive neurological disorders (26).”
NFL players & Chronic Traumatic Encephalopathy (CTE)
After Hall of Fame Pittsburgh Steeler center Mike Webster passed away in 2002, forensic pathologist and neuropathologist at the University of Pittsburgh’s School of Medicine, Dr. Bennet I. Omalu and his contemporaries published an article in Neurosurgery in 2005 that detailed the findings of Mike Webster’s brain examination. The results of Webster’s brain examination provided the first evidence of a link between the long-term neurodegenerative consequences that are associated with CTE and the exposure to repeated mild traumatic brain injury associated with football (29).
Since 2005, there has been an increase of former NFL players donating their brain to science. The VA and Boston University Center for the Study of CTE brain bank research data showed evidence of CTE in several deceased former football players. Public Broadcasting Service (PBS) highlighted FRONTLINE’s investigation into the NFL’s concussion crisis that documented the brain bank research evidence of CTE in 76 of the 79 former players examined (7). In 2015, the number diagnosed with CTE increased as 87 of the 91 former NFL players examined have tested positive for the brain disease (8).
Director of the VA and Boston University brain bank, Dr. Ann McKee told FRONTLINE that the identification of CTE after death suggested a clear link between football and traumatic brain injury (7). Since forty percent of those who tested positive were the offensive and defensive linemen, the results of the ongoing FRONTLINE investigation supported past research that suggested repeat, more minor head trauma that occurs frequently in football may pose the greatest risk to players, as opposed to just the less frequent vicious impacts that cause concussions (8).
Before 2013, to diagnose an athlete with CTE, researchers would collect a large sample of the player’s brain during autopsy. Examining the brain after death not only made early diagnosis impossible, it also made it difficult to prevent and treat the neurodegenerative disease associated with repetitive brain trauma. In 2012, in an effort to identify CTE before death, researchers injected a chemical that sticks to the tau protein into several former NFL players and used a PET brain-imaging method developed for Alzheimer’s to study the brains of living former NFL players.
In 2013, ESPN reported that the brain scan results of Fred McNeill (59), Wayne Clark (64), and three other unidentified players showed an abnormal protein buildup of tau concentrated in the area of the brain that controls memory, emotions, and other functions (15). Dr. Gary W. Small, the study’s lead author and a professor of psychiatry and bio behavioral sciences at UCLA, stated that although the findings are preliminary, “if they hold up in future studies, this may be an opportunity to identify CTE before players have symptoms so we can develop preventative treatment (15).”
NFL players & CTE symptoms
Even if an athlete who participates in football play has not suffered obvious concussions, the damage that is done during head to head collisions could have serious psychological consequences. Director of the Mount Sinai Center for Cognitive Health and NFL Neurological Center, Dr. Sam Gandy noted that “the frontal lobe of the brain often jostles around during head contact in football games, and the frontal lobe has an inhibiting effect that helps control behavior. Damage to the frontal lobe can compromise the inhibiting effect, and cause mood swings, even violence (17).”
Corsellis (1989) noted that “the onset of CTE is insidious, and affected individuals first notice deficits in attention, memory, and concentration leading eventually to confusion and disorientation. Over time, the condition progresses to dementia, poor judgment, irrational behavior, depression, and lack of insight. In advanced cases, Parkinsonism may develop (34).” In 2009, Professor of neurology and pathology at Boston University, Dr. Ann McKee published a study that linked athletes diagnosed with CTE with symptoms of irritability, impulsivity, aggression, depression, short-term memory loss and heightened suicidality 8–10 years after experiencing repetitive mild traumatic brain injury (24).
Later that year an NFL funded questionnaire based research revealed that younger NFL retirees suffered depressive symptoms. NFL retirees are much less likely to report episodes of anger (Intermittent Explosive Disorder), and older retired players suffered from memory-related illnesses at higher rates than the general population (46). In 2013, Dr. McKee and her pathology team conducted an autopsy analysis of the brain tissue, while another group led by Robert Stern, a neurologist and neurosurgeon at Boston University School of Medicine, carried out detailed interviews with deceased former NFL players’ families about the players’ lives, behaviors and symptoms.
McKee (et al., 2013) documented that 34 of 35 former professional football players had neuropathological confirmed CTE and suggested that the phases of CTE correlated with increased duration of play, continued existence after football and age at passing (25). “Symptoms in stage I chronic traumatic encephalopathy included headache and loss of attention and concentration. Additional symptoms in stage II included depression, explosivity, and short-term memory loss. In stage III, executive dysfunction and cognitive impairment were found, and in stage IV, dementia, word-finding difficulty and aggression were characteristic (25).”
Stern et al. (2013) suggested that the group whose initial presentation developed at a younger age involved behavioral and/or mood disturbances while the other group whose initial presentation advanced at an older age involved cognitive impairment (41). Later that year, UCLA’s research with the FDDNP-PET brain-imaging method documented that the former NFL players examined had greater symptoms of depression in addition to greater cognitive loss than healthy men (38). In 2014, UCLA researchers revealed to ESPN’s Outside the Lines that in case study interviews Tony Dorsett, Joe DeLamielleure, and Leonard Marshall mentioned experiencing cognitive and psychological effects (44).
After being diagnosed with signs of CTE, Mark Duper (45) also testified that he experienced memory loss, erratic behavior (emotional swings and panic attacks), depression, and suicidal thoughts (45). Dr. Gary Small, Professor of psychiatry and bio-behavioral sciences at UCLA, noted that “the findings suggested that FDDNP-PET could facilitate early recognition and intervention of trauma related neurodegeneration through premorbid detection. Providing a non-invasive means of early detection is a critical first step to developing interventions to prevent symptom onset and progression (38).”
Hyperbaric Oxygen Therapy Treatment
While researchers do not have a treatment for CTE yet, they’re clearly moving closer with every bit of testing and research that is done. After being diagnosed with signs of CTE, several NFL players decided to undergo two-hour hyperbaric chamber therapy sessions in hope of reversing the damage done to their brains. Although researchers are still exploring the hyperbaric chamber therapy as a treatment for TBI, the professional football players who underwent the two-hour therapy have benefitted from the hyperbaric oxygen treatment as documented by neurocognitive examinations and functional brain imaging.
The Mayo Clinic Staff (2014) noted that the air pressure in the hyperbaric chamber is amplified three times higher than normal allowing the lungs to increase oxygen intake and distribution helping to fight bacteria and stimulate the release of growth factors and stem cells, which promote healing (23). In 2011, Dr. Kenneth P. Stoller supervised the hyperbaric oxygen treatments of two football players that suffered from TBI/CTE. Although treatment commenced decades after injury in one case, the neurocognitive examinations and functional brain imaging of the two football players demonstrated improvement after being treated with hyperbaric oxygen (42).
In 2012, Joe Namath underwent hyperbaric oxygen therapy to reduce the brain damage suffered from years of TBI (22). After the completion of Namath’s therapy, Dr. Fox and Dr. Barry Miskin, chief of surgery at Jupiter Medical Center, reported seeing improvements in Namath’s neurological imaging examination and cognition test results (20). In 2014, after undergoing several 90-minute sessions in a hyperbaric chamber at Gracie’s Hope Hyperbarics, Hall of Famer Joe DeLamielleure told Charlotte Magazine that he also has witnessed apparent psychological and cognitive improvements (10).
The cited risk factors for suicide include mental disorders, depression, having firearms in the home, incarceration, family history, prior suicide attempt, violent behavior, and exposure to other people’s suicidal behavior, according to the National Institutes of Health (27). The American Foundation of Suicide Prevention suggested that people who commit suicide display warning signs through what they say or do. An individual’s suicide risk increases if a behavior is new or has increased due to change, while ultimately, people who are suicidal often display mood changes (2).
The more verbal, behavioral, and mood warning signs an individual demonstrates the greater the risk for suicide (2). In addition to an accumulation of warning signs, research suggested “that people who attempt suicide differ from others in many aspects of how they think, react to events, and make decisions. There are differences in aspects of memory, attention, planning, and emotion, for example. These differences often occur along with disorders like depression, substance use, anxiety, and psychosis (27).”
CTE and former NFL player suicides
After former Pittsburgh Steeler Justin Strzelczyk died in a blazing automobile crash in 2004, Dr. Omalu examined and found signs of CTE in Strzelczyk’s brain as well (36). Before his suicide, the American Psychiatric Association mentioned that Justin Strzelczyk was diagnosed with severe major depressive disorder and Omalu et al. (2006) mentioned that he had numerous previous suicide attempts (34). After former NFL defensive back Andre Waters committed suicide in 2006, Dr. Omalu and his contemporaries performed an autopsy analysis of Andre’s brain and discovered common features of CTE (9).
After the study on Andre’s brain, the New York Times reported that in a telephone interview, Dr. Omalu would later claim that “Andre sustained brain damage from playing football that led to his depression and ultimate death (35).” Former Atlanta Falcon lineman Shane Dronett showed signs of behavioral/mood changes before he committed suicide in 2009 and scientists at the Boston University School of Medicine’s Center for the Study of Traumatic Encephalopathy confirmed signs of Chronic Traumatic Encephalopathy (neurofibrillary tangles, neuropil threads, and cell dropout) in Shane’s brain (40).
In 2010, Dr. Bennet I. Omalu and his contemporaries examined CTE, suicides and para suicides in professional athletes. Omalu et al. (2010) documented that the brains of the four professional football players, who committed suicide, showed signs of the buildup of abnormal protein (tau) and displayed major depression, neuropsychiatric and cognitive impairments in addition to para suicides and suicides (31). Since a high percentage of people who commit suicide demonstrated or have been diagnosed with depression and other mental disorders, the researchers concluded that “CTE in our 5 cases may represent a common risk factor in our 5 cases (31).”
After Dr. Omalu’s 2010 findings, several former NFL players suffered cognitive and psychological changes that later lead to their suicide deaths and CTE diagnosis. Subsequently, during published case studies and investigational reporting interviews, family members and friends noted cognitive impairments like memory loss and psychological consequence like increased depression, irritability, aggression, and suicidal thoughts before the former NFL players committed suicide. February 2011, former Chicago Bears player Dave Duerson committed suicide by shooting himself in the chest and at his request donated his brain to the VA BU brain bank for CTE research purposes (33).
After the study was performed on Duerson’s brain, Dr. Ann McKee diagnosed him with CTE. Duerson’s son Tregg reported that the family witnessed the devastating effects of repetitive brain trauma when Duerson’s cognitive and psychological health started to decline (33). April 2012, ESPN reported that former Atlanta Falcons safety Ray Easterling committed suicide by shooting himself at the age of 62 (13). After Easterling’s death, the New York Times reported that the medical examiner documented signs of CTE and determined that it was the underlying condition that accounted for Easterling’s complications (43).
After Ray Easterling’s suicides death, his wife Mary Ann Easterling told FOXSports.com that once Ray’s career ended, Easterling suffered from dementia, depression and insomnia symptoms (3). May 2012, Hall of Fame Linebacker, Junior Seau, who was 43, committed suicide by shooting himself in the chest with a Smith & Wesson .357 magnum revolver (11). After Seau’s suicidal death, to determine a connection between Junior’s exposure to repetitive head injuries and his suicide death, Junior Seau’s family agreed to have his brain studied by the National Institutes of Health (12).
Eight month after Junior Seau’s suicidal death, the National Institutes of Health announced that, similar to autopsies of people with exposure to repetitive head injuries, researchers found evidence of the protein tau associated with CTE within multiple regions of Seau’s brain and scarring in the left frontal lobe of the brain (26). After Seau’s diagnosis, Seau’s son Tyler and ex-wife Gina told reporters that during the final years of Junior Seau’s life he suffered from frequent mood swings, depression, forgetfulness, and insomnia (14).
In December 2012, before shooting himself in the head in the team parking lot, Kansas City Chiefs linebacker Jovan Belcher shot and killed his girlfriend (17). After Javon Belcher’s suicide death, TIME magazine reported that dean of research and professor of pathology at the Touro College of Osteopathic Medicine, Dr. Piotr Kozlowski revealed that Jovan Belcher’s brain had “a buildup of abnormal tau protein levels in 7 out of 7 sections of the right and the left of the hippocampi that can cause nerve cell damage (17).” In 2013, former NFL safety, Paul Oliver grabbed his .40 caliber Glock and shot himself in the head (4).
The night Paul committed suicide, CNN reported Paul’s wife, Chelsea told police that Paul was depressed about the end of his career, unhappy with their relationship, and had made statements in the past about wanting to end his life (32). After Paul was diagnosed with CTE, Chelsea told HBO’s Real Sports that Paul’s aggression and lack of impulse control lead to domestic violence (28). In 2015, the New York Times reported that after displaying behavioral/mood changes, former National Football League linebacker Adrian Robinson Jr. committed suicide by hanging himself at the age of 25 and was later diagnosed with CTE (5).
The number of deceased former NFL players diagnosed with CTE by the VA and Boston University Center for the Study of Chronic Traumatic Encephalopathy brain bank research on TBI continues to increase as 76 of 79 former NFL players examined tested positive for CTE in 2014 and 87 of 91 tested positive in 2015. The number of living former NFL players examined and diagnosed with CTE also continues to increase as UCLA research use the FDDNP-PET brain-imaging method, developed for Alzheimer’s, to study the brains of living former NFL players.
The increase of autopsy case studies of deceased former NFL players and the FDDNP-PET brain-imaging case studies of living former NFL players has provided significant research evidence that there is a link between the buildup of the abnormal protein tau, associated with the neurodegenerative disease CTE, and the possibility of long-term neurological problems that typically don’t manifest until years after head trauma occurs. The case studies also suggested that the abnormal protein gathers around the blood vessels in the frontal cortex region, to cause brain cell damage that results in cognitive and psychological consequences.
After the suicide death of several former Nation Football League players, in published case study and investigational news reporting interviews, family members and close friends reported psychological changes like mood swings, depression, and suicidal thoughts. Furthermore, after diagnosing several living former Nation Football League players with CTE, during case study interviews, the UCLA FDDNP-PET brain-imaging method researchers documented player complaints of psychological changes (depression and suicidal thoughts) and cognitive impairments (confusion and memory loss).
Although similar studies on the relationship between CTE and suicide in former NFL players determined that further research was need to prove a connection (47, 22), the case study research and testimonial evidence discussed in this study reinforces Omula et al. (2010) findings that identified these psychological and cognitive consequences as key variables associated in suicide death of an alarming amount of NFL players, such as former Eagles and Arizona Cardinals Defensive Back Andre Waters, who resorted to suicide as a result of diminished neurological capabilities and accumulation of symptoms.
Although there is adequate case study research and testimonial evidence to conclude that there is a strong causal relationship between the presence of CTE and suicide in former NFL players as a result of their diminished psychological and cognitive capabilities, to establish a clearer connection, additional research should determine the extent to which the psychological and cognitive consequences are possible variables associated with former NFL player suicide. The challenge is no longer the acceptance of CTE as a diagnosis associated with former NFL players who committed suicide, but rather an account of the symptoms reported with exposure to identical repetitive head traumas before death.
Besides assisting in finding a suitable treatment that could reverse the effects of brain injuries like CTE, continued studies that use the FDDNP-PET brain-imaging method to measure the accumulation of tau protein in the brain should add accuracy to the determination of the effect and determine how dominant is the symptoms associated with the neurological disease. Ultimately, the detection of CTE in living, former NFL players not only further demonstrates the harmful impact of high-contact sports like football on the long-term safety and health, it could also help produce more answers to how the psychological and cognitive symptoms associated with CTE could take a football player’s will to live.
APPLICATION OF SPORT
Besides providing readers with the current research evidence on CTE, this study sheds light on testimonial evidence that has not been recorded or used for CTE research purposes. Since the research on suicides in former NFL players is still in its infancy, the sports community should place extreme importance on sharing and discussing all of the current literature available. Sharing information will not only help expand discussion that helps others in the sports industry realize the seriousness of the subject at hand, it will also help to emphasize the importance of expanding research efforts.
Acknowledgement: Marcos Abreu would like to acknowledge Yesenia Rivera and Ajani Abreu for all their love and support.
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