Chronic traumatic encephalopathy

Chronic traumatic encephalopathy (CTE) is a type of dementia associated with repeated blows to the head and recurrent episodes of concussion.

Chronic traumatic encephalopathy is particularly associated with contact sports, such as boxing or American football. Most of the available studies are based on ex-athletes.

It was previously known as "punch drunk" syndrome and dementia pugilistica. However, these terms are no longer used as it's now known that the condition isn't confined to ex-boxers.

There's still some debate about how widespread chronic traumatic encephalopathy is and how it should be diagnosed.

Currently, there are only supportive treatments available and research is focused on finding a reliable technique to diagnose the condition.

Symptoms of CTE

The symptoms of chronic traumatic encephalopathy may be similar to those seen in other types of dementia, particularly Alzheimer's disease.

Symptoms typically begin gradually several years after receiving repetitive blows to the head or repeated concussions.

They may include:

• short-term * memory loss* – such as asking the same question several times, or having difficulty remembering names or phone numbers
• changes in mood – such as frequent mood swings, depression, and feeling increasingly anxious, frustrated or agitated
• increasing confusion and disorientation – for example, getting lost, wandering, or not knowing what time of day it is
• difficulty thinking – such as finding it hard to make decisions

As the condition progresses, further symptoms may include:

• slurred speech (dysarthria)
• significant problems with memory
• parkinsonism – the typical symptoms of Parkinson's disease, including tremor, slow movement and muscle stiffness
• difficulty eating or swallowing (dysphagia) – although this is rare

Read more about the symptoms of dementia.

Causes of CTE

Any prolonged activity that involves repeated blows to the head or recurrent episodes of concussion is thought to increase the risk of chronic traumatic encephalopathy.

However, chronic traumatic encephalopathy and concussion are separate conditions.

Many people who are concussed don't go on to develop the condition, but evidence suggests a pattern of recurrent minor head injuries increases the risk.

Although the exact causes aren't fully understood, certain groups of people are believed to be most at risk, including:

• athletes with a history of repetitive mild traumatic brain injury – particularly in contact sports, such as boxing or martial arts, American football, football (perhaps related to repeatedly heading the ball) and rugby
• military veterans with a history of repeated head trauma – such as blast injuries
• people with a history of repeated head injuries – including self-injury, victims of recurrent assault, or poorly controlled epilepsy that results in recurrent head trauma

When to seek medical advice

If you're worried about your memory or think you may have dementia, it's a good idea to see your GP.

If you're worried about someone else, you should encourage them to make an appointment and perhaps suggest that you go along with them.

Memory problems aren't just caused by dementia – they can also be caused by:

• depression
• stress
• medications
• other health problems

Your GP can carry out some simple checks to try to find out what the cause may be, and they can refer you to a specialist memory clinic for more tests, if necessary.

Read about when to seek medical advice for:

• symptoms of concussion
• symptoms of a minor head injury

Diagnosing CTE

As chronic traumatic encephalopathy shares many features with other neurodegenerative conditions, there's currently no test available to diagnose the condition.

A diagnosis is usually based on a history of participating in contact sports, symptoms and clinical features.

Your GP will talk to you about the problems you're experiencing and may ask you to perform some simple mental or physical tasks, such as moving or walking around, to help with the diagnosis.

Your GP may refer you to a specialist memory assessment service, staffed by experts in diagnosing, caring for and advising people with dementia, and their families.

Memory clinic staff can listen to your concerns, assess your skills and, if necessary, arrange further tests to rule out other conditions.

Currently, the most reliable way of confirming a diagnosis of chronic traumatic encephalopathy is to examine a person's brain during an autopsy (an examination of the body after death) for certain changes.

These changes may not show up on routine brain scans or may occur in other conditions, which is why it can be difficult to confirm a diagnosis in life.

Research has found that the changes in the brain associated with chronic traumatic encephalopathy are different from those seen in Alzheimer's disease.

However, both conditions are associated with shrinking of the brain (atrophy) and the presence of neurofibrillary tangles that contain a protein called tau.

The most widely used test used for investigating neurodegenerative disorders is a magnetic resonance image (MRI) scan or computerised tomography (CT) scan.

Research is ongoing to determine whether other brain imaging techniques will be able to help diagnose chronic traumatic encephalopathy in the future.

Read more about:

• diagnosing concussion
• tests for diagnosing dementia
• what to do if you've just been diagnosed with dementia

Treating CTE

As with many other types of dementia, treatment for chronic traumatic encephalopathy is based around supportive treatments.

If you've been diagnosed with the condition, healthcare professionals, such as your GP or specialist, and social care services (normally your local council working with the NHS) will usually both be involved in helping draw up and carry out a long-term care plan.

You may also see a speech and language therapist or occupational therapist.

Read more about care plans for long-term conditions.

Dementia Choices provides detailed information for people with dementia and their families, including:

• help and support for people with dementia
• staying independent with dementia
• looking after someone with dementia
• dementia, social services and the NHS

It may also be helpful to get in touch with a local or national Alzheimer's or dementia support group, such as the Alzheimer's Society, for more information and advice.

Preventing CTE

The only known way to prevent chronic traumatic encephalopathy is to avoid repetitive head injuries. Although many head injuries are difficult to predict or avoid, there are ways to reduce your risk.

For example:

• wearing the recommended protective equipment during a contact sport
• following your doctor's recommendations about returning to play after concussion
• making sure any contact sport you or your child are taking part in is supervised by a properly qualified and trained person
• seeking medical advice if any symptoms of a previous head injury return

Read about:

• preventing minor head injuries 
• preventing concussion