Fact vs. Fiction: Examining the Reality of CTE (Chronic Traumatic Encephalopathy)

AUTHOR via CCMI – Erin Shapcott

Introduction.

In 2015, the movie Concussion brought the issue of brain injuries in sports into the spotlight, telling the story of Dr. Bennet Omalu, a forensic pathologist who identified chronic traumatic encephalopathy (CTE) in NFL players. The film focuses on his groundbreaking discovery of CTE and the intense resistance he faced from the NFL while trying to raise awareness about the dangers of repetitive head trauma.

While the movie Concussion sparked critical awareness about athlete safety and brain health, it may have oversimplified certain aspects of CTE. Movies and news articles often prioritize fear and drama to attract media attention, which can lead to one-sided views and misleading information. In the case of CTE, much of the research that the movie was based on was a series of preliminary case studies that offer relatively weak evidence.

Unfortunately, media portrayals often fail to report the caveats and limitations of these studies, leaving the public with an incomplete or exaggerated understanding of the issue. This article aims to provide more evidence-based and balanced insights into what we currently know about CTE, offering a clearer understanding of the progress and challenges in addressing this complex neurodegenerative disease.

What Is Chronic Traumatic Encephalopathy (CTE)?

CTE is a neurodegenerative disease characterised by the presence of tau protein deposits, particularly in areas of the brain involved in cognition, mood regulation, and motor function, such as the frontal cortex, hippocampus, and temporal lobes. These deposits are often located around blood vessels, a hallmark feature that differentiates CTE from other neurodegenerative conditions like Alzheimer’s disease. As CTE progresses, it can cause widespread brain atrophy, particularly in regions associated with higher-level cognitive functions (Bieniek, 2021). 

One key challenge in understanding CTE is that it can only be definitively diagnosed postmortem through an autopsy. During the autopsy, neuropathologists examine the brain for characteristic tau deposits and other signs of damage. Despite advances in research, no reliable method currently exists for diagnosing CTE in living individuals. This has made the disease challenging to study and limited our understanding of how it progresses over time. 

As a result, much of what is known about CTE is based on postmortem studies, making it a field of research still in its early stages.

Characteristics of CTE:

Iverson et al. (2021) have highlighted that no universally agreed-upon or validated clinical criteria exist for diagnosing CTE in a living person. However, several proposed diagnostic criteria have emerged in recent years, highlighting the complexity and ongoing debates within the scientific community. These criteria aim to identify standard features associated with CTE. 

Proposed clinical features often include a range of psychiatric, cognitive, and neurological symptoms. Key characteristics from various diagnostic frameworks include:

• Psychiatric Symptoms:Depression, suicidality, anger, aggression, violence, anxiety, agitation, apathy, paranoia, and substance abuse have all been considered in the diagnostic criteria. While most frameworks agree on the inclusion of these symptoms, some, like anxiety and substance abuse, remain less consistently highlighted.
  
  
• Cognitive and Neurological Changes:In most frameworks, cognitive decline or impairment is not required for diagnosis, though some emphasize it as a key criterion. Neurological signs, such as motor symptoms, are also inconsistently included, reflecting uncertainty about the progression of the disease.
  
  
• Natural History:The natural course of the disease is described in a significantly variable way. While some criteria suggest a delayed onset and progressive worsening of symptoms, others do not require these features for a diagnosis. Symptom duration also lacks standardization, further complicating the diagnostic process.
  
  

Iverson et al. (2021) explain how the significant challenges in diagnosing CTE lie in their overlap with other psychiatric and neurodegenerative disorders, making it challenging to attribute symptoms solely to CTE. More specifically, Iverson et al. (2021) research examined the prevalence of CTE symptom criteria in the general population, revealing that 6.6–11.9% of the general population met the symptom criteria for CTE. Broken down, we see that:

• 8–30.5% of people with chronic pain met CTE criteria
• 2–72.2% of people who experienced suicidality in the past year met CTE criteria
• The majority of women with both a mood disorder and chronic pain met the CTE criteria, with rates ranging from 62.7% to 89.8%.
  
  

This study highlights the high potential for misdiagnosis in individuals with chronic pain and other mental health issues. In addition, to complicate the matter further, some individuals with no reported symptoms exhibit CTE pathology in their brains. In contrast, others with significant cognitive or psychiatric symptoms show no evidence of CTE. As such, while proposed frameworks have expanded our understanding, evidence-based studies are needed to establish clear clinical guidelines for CTE.

Causes of CTE.

The primary cause of CTE is believed to be repetitive head impacts, which may cause micro-trauma to the brain. This trauma can lead to inflammation, neuronal damage, and the buildup of tau protein. However, not everyone exposed to repetitive head trauma develops CTE, suggesting that the relationship between head trauma and clinical symptoms is far more complex than previously understood.

Asken et al. (2016) highlight several biopsychosocial factors that may influence or modify the risk of developing CTE. These include developmental and demographic characteristics, neurodevelopmental disorders, normal aging, the transition to retirement, substance abuse, surgeries, anesthesia, and sleep disturbances. Additional factors such as chronic inflammation, alcohol use, obesity, and high blood pressure—commonly associated with neurodegenerative diseases—may also play a role in the onset or progression of CTE pathology. 

For example, Ramage et al. (2005) observed increased tau protein accumulation in opioid drug abusers. This is particularly significant given that Cottler et al. (2011) found 52% of retired NFL players reported opioid use—three times higher than the general population. These findings suggest that factors like substance abuse in retired athletes may contribute to CTE development, either in conjunction with or independently of past head injuries.

As such, CTE is likely influenced by a multifaceted interplay of head trauma, biopsychosocial factors, and broader health conditions. The variability in symptom presentation and pathology highlights the need for further research into the underlying mechanisms. While repetitive head impacts remain a significant contributor, other factors may play critical roles.

Who is at Risk for CTE?

CTE is traditionally associated with individuals exposed to repetitive head trauma, such as athletes in contact sports, military personnel, and those with a history of frequent concussions (McKee et al., 2023). However, emerging research indicates that CTE may not be exclusive to these groups. Recent studies have found CTE pathology in people with no known history of repetitive head trauma (Iverson et al., 2019). 

Ongoing research is needed since most studies have lacked control brains, and all the brains examined came from a similar demographic background—athletes with a history of concussions. This lack of comparison with a more diverse sample, including individuals without head trauma, makes it difficult to generalize the findings to the broader population. Furthermore, people who donate their brains for research often do so because they have experienced neurological or psychiatric issues, which introduces another bias to the study’s conclusions. This highlights the need for more representative and balanced samples in CTE research to avoid skewed results.

The Science of CTE Then and Now.

When Concussion was released in 2015, much of what we knew about CTE stemmed from postmortem studies of athletes’ brains. Over the years, an important area of progress is the growing recognition that CTE is not exclusive to professional athletes or solely linked to head trauma. Emerging research examining control brains—those from individuals without known exposure to repetitive neurotrauma—has revealed that CTE pathology can occur in a broader range of individuals. These findings have broadened the understanding of how and why CTE develops (Pierre et al., 2021).

Furthermore, in 2019, the term Traumatic Encephalopathy Syndrome (TES) was introduced to describe the clinical symptoms observed in living individuals who may have CTE. The key distinction is that CTE is a post-mortem diagnosis based on brain tissue examination, whereas TES is a clinical diagnosis that may indicate potential CTE development (Katz et al., 2021).

However, the criteria for TES has significant limitations and has not proven to be a reliable diagnostic tool, often leading to over-diagnosis and misdiagnosis. Terry et al. (2024) found that approximately one in four older adults met the symptom criteria for TES, even without a history of repetitive neurotrauma, with mental health and sleep issues playing a larger role than contact sports history. These findings highlight the need to refine TES criteria to improve diagnostic accuracy.

In response to these challenges, researchers have been working to improve imaging techniques and identify biomarkers specific to CTE. However, significant limitations remain. In 2015, the inability to diagnose CTE in living individuals forced researchers and clinicians to rely solely on postmortem studies—a challenge that persists today. While advancements in imaging and biomarker research offer promise, they are not yet reliable enough for widespread clinical use. Additionally, much about the disease’s progression remains unclear, including why some individuals with extensive head trauma never develop CTE, while others with less exposure do. These unanswered questions underscore the complexity of CTE and the ongoing need for further research.

Despite these advancements, critical questions remain unanswered. How can we reliably diagnose CTE in living individuals? What are the long-term effects of concussions? And how can we better tailor prevention and treatment strategies to individual risk factors? As researchers continue to unravel these complexities, collaboration between scientists, sports organizations, and healthcare providers will be essential to improving outcomes for those affected by CTE.

What’s Next for Athlete Safety and Awareness.

For now, the best approach to CTE requires a multifaceted approach centred on education, prevention, research, and advocacy. 

Proper Concussion Prevention and Management.

Since the release of the movie Concussion, the NFL and other sports organizations have implemented significant measures to address CTE risks due to head injury. These include enhanced concussion protocols, limiting full-contact practices, modifying rules to reduce high-impact collisions, and investing millions in brain health research. 

Youth and other professional sports leagues have followed suit, adopting mandatory concussion education, stricter return-to-play policies, and improved equipment standards. Prompt removal from play after suspected concussions, combined with proper medical management and return-to-play guidelines, is essential for long-term brain health.

While the total number of concussions an individual sustains is often a focal point in discussions about brain health, emerging research suggests that the timing and management of these injuries may be even more critical. 

Meehan et al. (2012) highlighted that closely spaced concussions are more likely to lead to severe long-term damage, underscoring the importance of ensuring proper recovery time between injuries. Inadequate recovery periods may leave the brain more vulnerable to subsequent trauma, compounding the risk of long-term neurocognitive issues. This finding emphasises the need for diligent medical management, including strict adherence to return-to-play protocols and individualised recovery plans prioritising the brain’s healing process.

The Importance of Education.

Education also remains a cornerstone of prevention. Staying informed about concussions and brain health is vital, but it’s equally important to approach information critically. Media portrayals of head injuries, such as those in Concussion, can lead to public misconceptions and unnecessary panic, often exacerbating fears about CTE.

Research suggests that the fear of CTE itself may contribute to worsening mental health outcomes. For example, a recent study by Grashow et al. (2024) surveyed 4,180 former professional football players, revealing that 34.4% of participants (681 individuals) believed they had CTE. This perception, whether accurate or not, was strongly associated with increased symptoms of depression, anxiety, and reduced quality of life.

This highlights the importance of balanced messaging…

While it is essential to educate the public about the risks of head trauma and encourage preventative measures, overemphasizing the dangers without sufficient context can have unintended consequences. Athletes and their families must be reminded that a single concussion or even multiple concussions do not guarantee a progressive neurodegenerative condition like CTE. 

Instead, the focus should be on comprehensive prevention strategies, appropriate medical management, and maintaining a healthy, balanced lifestyle.

Prioritising Mental Health.

Mental health plays a significant role in overall well-being and can often overlap with symptoms of brain injuries, such as mood swings, depression, and anxiety. Neuropsychological assessments can help differentiate between issues caused by trauma and those stemming from other sources, guiding more targeted interventions. By prioritizing mental health, individuals can address coexisting conditions that may exacerbate symptoms, contributing to better overall outcomes.

Staying Cognitively and Socially Active.

 Engaging in cognitive and social activities is another critical component of brain health. Activities that challenge the brain—such as puzzles, reading, learning new skills, or playing strategy-based games—help maintain cognitive function and neuroplasticity. Social interactions also protect against brain health issues such as isolation and stress. Maintaining an active and connected lifestyle can support recovery and promote long-term cognitive resilience.

Reducing Inflammation and Promoting Brain Health.

Inflammation is increasingly recognised as a key factor in brain health, particularly after head trauma. Lifestyle modifications to reduce inflammation can significantly support recovery and overall brain function.

These include:

1. Avoiding Alcohol and Opioids:Alcohol and opioid use can increase inflammation, impair brain function, and slow recovery. Steering clear of these substances can help protect the brain and improve outcomes.
   
   
2. Maintaining a “Clean” Diet:A nutrient-dense diet rich in fruits, vegetables, whole grains, lean proteins, and healthy fats (such as omega-3s) can combat inflammation. Berries, leafy greens, nuts, and fatty fish are particularly beneficial for brain health.
   
   
3. Regular Exercise:Moderate aerobic exercise improves blood flow to the brain, reduces inflammation, and supports mood regulation. Walking, swimming, or cycling are excellent options.
   
   
4. Sleep Hygiene:Quality sleep is critical for brain recovery and overall health. Establishing a consistent sleep schedule, creating a restful environment, and avoiding screens before bedtime can enhance sleep quality.
   
   
5. Improving Mood:Mental well-being and mood regulation are closely tied to inflammation and brain health. Practices like mindfulness, meditation, or therapy can help manage stress and reduce inflammatory markers in the body.

Conclusion.

While the movie Concussion succeeded in bringing the dangers of CTE into the public eye, it also demonstrated the power of the media in shaping public knowledge. It is crucial to balance awareness and accurate reporting regarding CTE. Misleading information can create misconceptions and fear, thereby hindering informed decision-making. 

As the science surrounding CTE evolves, we must continue to educate the public, improve safety protocols, and advocate for policies that protect athletes’ well-being. Only through ongoing research, education, and advocacy can we ensure the safety and health of athletes at all levels, from youth sports to professional leagues. 

A commitment to evidence-based approaches will be vital in safeguarding the future of athlete health and brain safety.

If you are interested in our concussion services? Get in touch today and a member of the team would be delighted to help 

ABOUT THE AUTHOR

Erin Shapcott

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