Chronic traumatic encephalopathy (CTE) is a degenerative brain disorder that happens due to repeated head impacts. This condition usually affects athletes who play contact sports, but can affect military personnel and people who participate in other sports and activities. Preventing head injuries is the best way to address this permanent condition.
Chronic traumatic encephalopathy (CTE) is a brain condition that can develop due to repeated head impacts and concussions. This condition affects how areas of your brain function, communicate and work with each other. Depending on the extent of the damage and the affected brain areas, this condition can have severe effects.
CTE is best known for affecting professional athletes in contact sports, especially boxing, American football and ice hockey. However, this condition can develop in people with repeated head impacts regardless of their sport (or if they don’t play sports at all). Healthcare providers also identify it in military veterans who experienced multiple explosion- or blast-related incidents.
The name of CTE breaks down like so:
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Chronic traumatic encephalopathy can affect anyone with a history of repeated blows to the head. However, CTE also doesn’t appear immediately. For most people with this condition, it can take years or decades before symptoms are severe enough to draw attention. People who develop CTE typically have a history of many head impacts over several years, especially people who play sports professionally. The vast majority of people who play high school sports don’t develop CTE. In fact, the average age of people with confirmed CTE is around 42 to 43 years old.
People who have the greatest risks include:
Experts aren’t sure just how common CTE is. That’s partly because there’s no way to diagnose this condition while a person is alive. Healthcare providers can suspect a person has it, but there’s no way to confirm it without an autopsy. CTE also has strong similarities and shares symptoms with several other degenerative brain diseases, such as Alzheimer’s disease and frontotemporal dementia.
The symptoms of CTE tend to develop slowly and get worse over time.
Common symptoms of CTE can include:
Other symptoms that can occur include:
CTE happens because of a combination of factors. These factors include:
There’s no conclusive way to diagnose CTE while a person is alive. The only way to do that is to examine samples of a person’s brain under a microscope, which is only possible during an autopsy after death.
While experts may not be able to confirm CTE before death, they can still make a presumptive diagnosis based on your symptoms and a physical and neurological exam. They’ll also review your history of head injuries and recommend certain lab and imaging tests. The most common tests don’t diagnose CTE. Instead, they rule out other conditions. They include:
There’s no cure for CTE. Treatments for some of the symptoms are possible, and these vary depending on your symptoms, medical history and more. In addition, there are a number of habits you can incorporate in your lifestyle that helps brain health in general. Your healthcare provider is the best person to tell you about the treatments they recommend and why.
Reducing the number of head impacts you experience is ultimately the best way to reduce the risk of CTE. In addition, there are simple measures that can reduce the chance of having a concussion, where blows to the head can cause notable symptoms:
As noted earlier, CTE is a degenerative brain disease. That means it’s progressive, and the symptoms will get worse over time. This can take years or even decades. Experts currently don’t have a way to predict how long it may take to see the decline in brain function.
CTE is a permanent, lifelong condition.
Currently, the available research and understanding of CTE indicate this condition isn’t deadly on its own. Instead, it causes other health concerns that negatively affect your health and well-being. This includes a gradual loss of the ability to feed, bathe or dress yourself. People with these issues often need to live in a long-term care or skilled nursing facility staffed 24/7 with medical personnel.
In the earlier stages of this condition, it’s possible to care for yourself with the guidance of a healthcare provider. They can advise you on treating and managing your symptoms and what you can do with your lifestyle to adapt. As this condition worsens, taking care of yourself may become more difficult. Unfortunately, that means you may not be able to live independently after symptoms reach a certain point.
If you have an early diagnosis of CTE (or any other kind of degenerative brain disease), you should talk to your healthcare provider, your family or loved ones, and anyone you trust to make important decisions for you. These discussions are important because they can guide caregivers and loved ones on what you want for yourself if the time comes when you can’t choose for yourself.
These conversations may feel difficult, uncomfortable or unpleasant. Despite that, you should have them and do so sooner rather than later. That helps your loved ones know ahead of time what you want for yourself when you can no longer make those choices. It also means your loved ones don’t have to guess what you want.
In addition to those conversations, you should put your wishes and decisions in writing. That includes preparing documents connected to legal issues and what happens if you can’t care for yourself or make decisions for your care or well-being. Many people consult an attorney to prepare these documents, but you may be able to prepare some on your own (you may need a notary or other official to endorse them, depending on the laws in your area).
You should see a healthcare provider if you notice any symptoms of problems with your ability to think, remember or concentrate or if there are changes in your mood or behavior.
You should get immediate help if you have thoughts about harming yourself, including thoughts of suicide, or about harming others. You should also seek immediate help if you suspect someone you know is in imminent danger of harming themselves.
To get help in these situations, you can call any of the following:
People sometimes use the terms “post-concussion syndrome (PCS)” and “chronic traumatic encephalopathy” interchangeably, but these aren’t the same condition.
A note from Cleveland Clinic
Chronic traumatic encephalopathy (CTE) is a condition that can affect people who have a history of repeated head impacts or concussions. It typically takes years or even decades to develop. This condition falls under degenerative brain diseases, which means it progressively damages your brain over time. Unfortunately, it’s incurable and permanent.
While there’s no cure, there are many things you can do to prevent it. Avoiding significant, repeated blows to the head is key, especially by using safety gear and safe practices while participating in contact sports or activities with a greater risk of head injury. Research is also ongoing for this condition, and experts are continuing to unravel how this condition happens and possible treatments that could offer hope to people in years to come.
Last reviewed by a Cleveland Clinic medical professional on 12/09/2022.
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