Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative disorder that seems to be connected to repetitive head injuries. The challenge in identifying and treating this disorder is that CTE can only be diagnosed after death with an autopsy of the brain.
While much is still unknown regarding its exact cause, treatment and prevention, CTE has gained attention in the sports world for its potential connection to concussion and repetitive hits to the head. Traumatic brain injuries sustained in contact sports, domestic violence or other circumstances seem to be associated with CTE.
Here’s what you need to know about the risk factors, symptoms, diagnosis, treatment options and research about this brain disorder.
Researchers are still not clear on the exact relationship between head injuries and CTE. While individuals who develop CTE have sustained multiple head impacts, the exact connection is unknown. CTE appears to be linked to repetitive trauma, rather than a single incident, but researchers don’t know the number of head injuries that increase the chance of CTE or whether it matters how close in time or over what time period they occur.
Head injuries are not limited to significant incidents such as diagnosed or self-reported concussions. Recent research has found that subconcussive hits—repetitive impacts to the head that do not result in diagnosable symptoms—may also contribute to CTE. It’s also unclear whether genetic risk factors may play a role.
Doctors may note certain neurological symptoms as potential signs of CTE. The disorder can cause cognitive, mood, and behavioral changes, including difficulty thinking, short and/or long-term memory loss, depression and anxiety, emotional instability, impaired judgment, impulsive or erratic behavior such as aggression, paranoia, headaches, suicidal thoughts or behavior, and eventually progressive dementia.
Because this brain disease can only be officially diagnosed with an autopsy of the brain, doctors are not able to diagnose living patients. The brain autopsy looks for a clumping or accumulation of a certain type of protein called tau within the brain.
Symptoms of CTE often go unnoticed for years, even decades, after head trauma occurs. Although symptoms can be managed, there isn’t a cure for the disease. And because there isn’t a scientifically known cause for CTE, many doctors hesitate to set exact guidelines for its prevention. With the apparent association with repetitive head trauma, there is a belief that avoiding that type of impact and decreasing risk of concussion would be helpful in preventing CTE.
In sports like football, proper playing technique and increased neck strength may help reduce head impact and movement, providing protection to the brain. Sideline and return-to-play protocols are also important for monitoring, managing, and rehabilitating head trauma.
With more research, we will learn more about this disease—its cause, additional risk factors, and ways to diagnose and treat it. The good news is that recent sports and news media headlines have sparked a growing awareness of the disease and propelled further research.
Current research is mainly focused on identifying a biomarker or higher levels of the tau protein to aid in diagnosis of CTE while patients are still alive. But even if doctors are able to diagnose CTE, it’s still unclear exactly how head injuries or hits to the head cause CTE.
To help increase awareness of traumatic brain injuries and fund continued research on prevention and treatment, the American Brain Foundation has established the Traumatic Brain Injury Fund and welcomes support from donors.
We need your help to continue to fund brain research projects and find cures. Stand with us in the fight against brain diseases and disorders.
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