CTE Medical Diagnosis: Understanding Chronic Traumatic Encephalopathy

Chronic Traumatic Encephalopathy (CTE) is a progressive brain condition believed to be caused by repeated head injuries. This degenerative disease leads to the death of nerve cells in the brain, and unfortunately, it can only be definitively diagnosed post-mortem through a brain autopsy.

While CTE remains a relatively rare and not fully understood disorder, it’s crucial to recognize that it is linked to repeated, not singular, head trauma. Often associated with contact sports and military combat situations, CTE development has also been connected to second impact syndrome, where a subsequent head injury occurs before the symptoms of a prior injury have completely subsided.

Experts are actively researching the complexities of how repeated head injuries and other contributing factors trigger the brain changes characteristic of CTE. Current research is focused on determining how the frequency and severity of head injuries impact the risk of developing CTE.

Studies have identified CTE in the brains of individuals who participated in high-impact sports such as American football and boxing, as well as in military personnel exposed to explosive blasts. The symptoms of CTE are thought to be wide-ranging, encompassing difficulties with cognition, emotional regulation, physical coordination, and behavior. These symptoms typically manifest years, even decades, after the initial head trauma.

Currently, a definitive Cte Medical Diagnosis cannot be made during a person’s life, except in cases with a clear history of high-risk exposures. Researchers are diligently working on developing diagnostic biomarkers for CTE, but none have yet been clinically validated. In the meantime, when individuals present with symptoms suggestive of CTE, healthcare providers may diagnose Traumatic Encephalopathy Syndrome as a clinical approximation.

The precise prevalence of CTE in the general population is still unknown, though it appears to be uncommon. Similarly, the exact causes are still under investigation, and there is currently no known cure for CTE.

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Symptoms of CTE and the Diagnostic Challenge

No single symptom is uniquely indicative of CTE, and many potential symptoms overlap with other medical conditions. In confirmed CTE cases diagnosed via autopsy, a range of cognitive, behavioral, mood, and motor changes have been observed.

Cognitive Impairment and CTE Diagnosis

• Trouble Thinking: Difficulties in processing information and making decisions.
• Memory Loss: Challenges in recalling recent events or previously learned information.
• Problems with Planning and Organization: Struggling to strategize, organize tasks, and execute plans effectively.

Behavioral Changes in CTE

• Impulsive Behavior: Acting without thinking through consequences.
• Aggression: Increased irritability, anger outbursts, or physical aggression.

Mood Disorders and CTE

• Depression or Apathy: Persistent sadness, loss of interest in activities, and emotional numbness.
• Emotional Instability: Rapid and unpredictable shifts in mood.
• Substance Misuse: Development of problems with alcohol or drug use, potentially as a coping mechanism.
• Suicidal Thoughts or Behavior: Thoughts of self-harm or attempts to end one’s own life.

Motor Symptoms Associated with CTE

• Problems with Walking and Balance: Difficulty maintaining balance and coordinating movements.
• Parkinsonism: Symptoms similar to Parkinson’s disease, including tremors, slow movements, and speech difficulties.
• Motor Neuron Disease: Damage to nerve cells controlling voluntary muscle movement, impacting walking, speaking, swallowing, and breathing.

It’s crucial to understand that CTE symptoms do not appear immediately following a head injury. Medical experts believe that the symptoms develop gradually over many years or even decades after repeated head trauma has occurred.

Furthermore, experts have observed what may be two distinct presentations of CTE symptoms. The first form may manifest earlier in life, typically between a person’s late 20s and early 30s, primarily involving mental health and behavioral issues such as depression, anxiety, impulsivity, and aggression. The second form tends to emerge later in life, around age 60, characterized by memory and thinking impairments that are likely to progress into dementia.

It’s important to acknowledge that the complete spectrum of signs associated with CTE, even in post-mortem examinations, is still being defined. Additionally, our understanding of the progression of CTE remains limited, which further complicates the process of developing reliable diagnostic tools for living individuals.

When to Seek Medical Advice Regarding Potential CTE Symptoms

Given the potential for overlapping symptoms with other conditions and the current limitations in CTE medical diagnosis during life, it is essential to consult a healthcare provider in certain situations:

• Suicidal Thoughts: Research indicates a heightened risk of suicide in individuals with CTE. If you are experiencing thoughts of harming yourself, seek immediate help by calling 911 or your local emergency number. You can also contact a suicide hotline; in the U.S., dial or text 988 to reach the 988 Suicide & Crisis Lifeline or use the Lifeline Chat.
• Head Injury: If you have sustained a head injury, even if it did not require emergency room treatment, it’s advisable to see your healthcare provider for evaluation and guidance. If you are concerned about a head injury your child has experienced, contact your child’s healthcare provider promptly. Depending on the symptoms, immediate medical attention may be recommended.
• Memory Problems: If you have concerns about your memory or are experiencing other difficulties with thinking or behavior, consult your healthcare provider for assessment.
• Personality or Mood Changes: If you notice persistent depression, anxiety, aggression, or impulsive behavior, seeking medical advice is important to determine the underlying cause and appropriate management.

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Causes of CTE: Repeated Head Trauma

Concussion: A Key Factor in CTE

Image alt text: Illustration depicting a concussion, highlighting the brain’s movement within the skull due to a blow to the head.

Repeated head trauma is strongly believed to be the primary cause of CTE. Much of the research on CTE has focused on American football players, ice hockey players, and military personnel serving in combat zones, due to their higher risk of repeated head impacts. However, it’s important to recognize that other sports and situations, such as physical abuse, can also lead to repeated head injuries and potentially contribute to CTE.

A head injury can result in a concussion, which can manifest with symptoms like headaches, memory problems, and other neurological issues. However, it is crucial to note that not everyone who experiences repeated concussions will develop CTE. Some studies have even indicated no increased incidence of CTE in populations exposed to repeated head injuries, suggesting that other factors may also be involved.

In brains affected by CTE, researchers have consistently found an abnormal buildup of a protein called tau around blood vessels. This tau accumulation in CTE is distinct from the tau patterns observed in Alzheimer’s disease and other forms of dementia, highlighting CTE as a unique neuropathological entity. CTE is thought to cause brain atrophy, where areas of the brain waste away due to damage to nerve cells and disruption of communication between cells.

It’s also possible for individuals with CTE to exhibit signs of other neurodegenerative diseases, including Alzheimer’s disease, amyotrophic lateral sclerosis (ALS), Parkinson’s disease, or frontotemporal lobar degeneration (frontotemporal dementia), further complicating clinical diagnosis and highlighting the need for specific CTE biomarkers.

Risk Factors for CTE

Repeated exposure to traumatic brain injury is considered the major risk factor for developing CTE. However, research is ongoing to further clarify the specific risk factors and their relative contributions. Understanding these risk factors is essential for developing effective prevention strategies and potentially improving early CTE medical diagnosis in the future.

Prevention of CTE

Currently, there is no treatment to cure CTE. However, because CTE is linked to recurrent concussions, prevention strategies are paramount. Individuals who have experienced one concussion are at a higher risk of subsequent head injuries. Therefore, the prevailing recommendation for CTE prevention is to minimize mild traumatic brain injuries and to prevent further injury after a concussion has occurred. This includes promoting safety measures in sports, military training, and other activities that carry a risk of head injury.

By Mayo Clinic Staff

Chronic traumatic encephalopathy care at Mayo Clinic

Diagnosis & treatment

Nov. 18, 2023

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