Forensic neuropathologist Bennet Omalu had no idea that the autopsy he was about to perform would turn the all-powerful National Football League on its head. Mike Webster, legendary NFL Hall of Famer, had died at 50 years of age due to a heart attack after several financial difficulties and intense pain that led him to lose his mind. After dissecting his brain, Omalu observed that Webster had brain damage similar to that of people with Alzheimer’s or dementia. The repeated blows he had received to the head throughout his sporting career were probably the reason why Webster was suffering from symptoms of dementia similar to those suffered by many boxers. The neurodegenerative findings were compatible with the concept that Omalu himself called chronic traumatic encephalopathy or CTE, a neurodegenerative disorder that particularly affected American football players as a consequence of the accumulation of brain trauma caused by their sporting activity. The results published in Neurosurgery magazine in 2005,1 shook the foundations of the National Football League to the point that it set in motion its powerful legal and scientific teams to discredit Omalu as a ‘nobody’ and make him the public enemy number 1 of the American game.
However, cases of former American football players dying under strange circumstances continued to be drawn to Omalu’s attention. Shortly after, his laboratory received the brain of Terry Long, who committed suicide at the age of 45 by swallowing antifreeze. The worst fears were met, for he also had CTE. In Omalu’s words, Long’s brain looked “more like a 90-year-old brain with advanced Alzheimer’s” than that of a 45-year-old man. Once again the results were published in Neurosurgery,2 one of the most prestigious scientific journals in its field, with the NFL unable to do anything to stop it. And so on up to 17 cases.
These events became so big that, despite the many obstacles put up by the NFL, the movie “Concussion” was recently released, starring none other than Will Smith in the role of Dr. Omalu. The term used in the title refers to a temporary loss of brain function caused by a trauma getting into the brain, repeated exposure to which is related to the development of long-term neurodegenerative disorders.3
Heading the ball in soccer is also a problem
Although there is much evidence supporting the idea that elite athletes are at a lower risk of death associated with cardiovascular diseases and cancer than the general population,4 the long-term neurocognitive consequences of playing contact sports are uncertain. And this problem is not exclusive to American football. For example, recent research by Dr. Michael Lipton of the Albert Einstein College of Medicine, New York has determined that the average amateur football player heads the ball more than 1,000 times a year,5 having established a threshold of 885 balls to the head per year after which deterioration in cognitive performance begins to occur.6
A new study by researchers at the University of Glasgow (Scotland) on former professional football players was recently published in The New England Journal of Medicine and gained considerable media coverage.7 The results showed that ex-footballers had a 3 times greater risk than the general population of death from neurodegenerative disorders. These account for 1.7% of deaths among former football players as opposed to 0.5% among non-athletes. Moreover, the risk of death from Alzheimer’s is 5 times higher, is 4 times as high for ALS (amyotrophic lateral sclerosis) and twice as high for Parkinson’s. Meanwhile, when analysing the medications that are prescribed to retired football players, it was found that they were 5 times more likely to take drugs for dementia than non-athletes. Despite these results, it is not all bad news for football players, for it was also found that they have a lower risk of death from non-neurological diseases (lower general mortality from cardiovascular disease and cancer) compared to the general population.7
Looking into the positive news in greater depth, a recent study published by the same group of researchers at the University of Glasgow found that these same former professional footballers had a lower risk of suicide (another of the problems associated with American football and repeated blows to the head) than the general population.8 Similarly, former football players were at a lower risk of hospitalisation for mental health disorders such as those related to anxiety, stress, depression, drug or alcohol use and bipolar disorders compared to non-athletes.8
Despite some of the results presented herein, we do not intend to be alarmist or to question participation in sports like football and American football, but simply to emphasise the importance of actively monitoring the neurocognitive health of people who play these sports in particular, and all contact sports in general. Furthermore, as we have seen, elite sport provides many health benefits, as reflected for example by the lower risk of death from cancer and cardiovascular disease compared to the non-athlete population.
Javier S. Morales
- Omalu BI, DeKosky ST, Minster RL, Kamboh MI, Hamilton RL, Wecht CH. Chronic traumatic encephalopathy in a National Football League player. Neurosurgery. 2005;57(1):128-34.
- Omalu BI, DeKosky ST, Hamilton RL, Minster RL, Kamboh MI, Shakir AM, Wecht CH. Chronic traumatic encephalopathy in a national football league player: part II. Neurosurgery. 2006;59(5):1086-92.
- Hay J, Johnson VE, Smith DH, Stewart W. Chronic Traumatic Encephalopathy: The Neuropathological Legacy of Traumatic Brain Injury. Annu Rev Pathol. 2016;11:21-45.
- Garatachea N, Santos-Lozano A, Sanchis-Gomar F, Fiuza-Luces C, Pareja-Galeano H, Emanuele E, Lucia A. Elite athletes live longer than the general population: a meta-analysis. Mayo Clin Proc. 2014;89(9):1195-200.
- Levitch CF, Zimmerman ME, Lubin N, Kim N, Lipton RB, Stewart WF, Kim M, Lipton ML. Recent and Long-Term Soccer Heading Exposure Is Differentially Associated With Neuropsychological Function in Amateur Players. J Int Neuropsychol Soc. 2018;24(2):147-155.
- Lipton ML, Kim N, Zimmerman ME, Kim M, Stewart WF, Branch CA, Lipton RB. Soccer heading is associated with white matter microstructural and cognitive abnormalities. Radiology. 2013;268(3):850-7.
- Mackay DF, Russell ER, Stewart K, MacLean JA, Pell JP, Stewart W. Neurodegenerative Disease Mortality among Former Professional Soccer Players. N Engl J Med. 2019;381(19):1801-1808
- Russell ER, McCabe T, Mackay DF, Stewart K, MacLean JA, Pell JP, Stewart W. Mental health and suicide in former professional soccer players. J Neurol Neurosurg Psychiatry. 2020:jnnp-2020-323315.