Chronic Traumatic Encephalopathy (CTE)

Chronic traumatic encephalopathy (CTE) is a brain condition associated with repeated blows to the head. Potential signs of CTE are problems with thinking and memory, personality changes, and behavioral changes including aggression and depression. People may not experience potential signs of CTE until years or decades after brain injuries occur. A definitive diagnosis of CTE can only be made after death, when an autopsy can reveal whether the known brain changes of CTE are present.

• What causes CTE?
• Symptoms
• Diagnosis
• Treatment
• Research

What causes CTE?

Emerging evidence suggests that individuals who have experienced repeated traumatic brain injuries (concussions) or multiple blows to the head without loss of consciousness, such as professional athletes and combat veterans, are at higher risk of developing CTE than individuals who have not experienced repeated brain injuries.

Physical evidence connecting football and CTE was first discovered by Bennet Omalu, M.D., a forensic neuropathologist who performed an autopsy on Mike Webster, the Hall of Fame center for the Pittsburgh Steelers. His story was made into the movie "Concussion," which has heightened awareness of CTE.

Previously, CTE had been associated with boxing and was called dementia pugilistica or "punch-drunk syndrome". The risk of CTE in boxers seems most closely tied to the number of rounds boxed, not to the number of times a boxer was knocked out, suggesting that even repeated blows to the head that don't cause unconsciousness may increase CTE risk.

 

Symptomsback to top

Physicians and researchers are only beginning to understand many aspects of CTE. More time and research are needed. For that reason, consensus has not yet been reached on the symptoms of CTE. However, based on present knowledge, the signs of CTE may sometimes be similar to those of other conditions that involve substantial loss of brain cells, including Alzheimer's disease and Parkinson's disease. Possible signs include:

• Memory loss
• Confusion
• Personality changes (including depression and suicidal thoughts)
• Erratic behavior (including aggression)
• Problems paying attention and organizing thoughts
• Difficulty with balance and motor skills

Researchers believe CTE is related to the buildup of an abnormal form of a protein called tau in the brain. This buildup, which is also an Alzheimer’s hallmark, leads to brain cell death. Deposits of a protein called beta-amyloid that are another Alzheimer’s hallmark are found in some individuals with CTE, but are not common.

 

Diagnosisback to top

Currently, there is not a test to determine if someone has CTE. Because CTE is a relatively new area of exploration for researchers and physicians, formal clinical guidelines for diagnosing and managing CTE do not yet exist. A definitive diagnosis can only be made through an autopsy after death.

Scientists are working to further understand CTE and to identify ways to diagnose CTE during life.

When CTE is suspected, a thorough medical history, mental status testing, neurological exams, brain imaging and further diagnostic tests may be used to rule out other possible causes.

 

Treatment back to top

Today, there is no treatment and no cure for CTE. The only known way to prevent it is to avoid repeated head injuries.

Those with potential signs of CTE may benefit from some of the same types of care provided for people with Alzheimer’s disease and other types of dementia (for example, behavioral approaches to deal with aggression).

People who are caring for someone with signs of CTE can be helped by knowing what to expect as CTE progresses and from having a support network in place. Information and resources are available in our Caregiver Center.

 

Researchback to top

Several major research initiatives are under way to gain further insight into the patterns

of injury and brain changes that may be implicated in CTE, and to develop new strategies for prevention, diagnosis and treatment. To date, the Alzheimer's Association has invested more than $2 million in research on brain injury, including CTE.

For more information back to top

Alzheimer's Association Traumatic Brain Injury (TBI) page