Merck Manual

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Chronic Traumatic Encephalopathy (CTE)

(Dementia Pugilistica)


Juebin Huang

, MD, PhD, Department of Neurology, University of Mississippi Medical Center

Reviewed/Revised Feb 2023

Chronic traumatic encephalopathy (CTE) is a progressive degenerative brain disorder that may occur after repetitive head trauma or blast injuries.

Dementia pugilistica, identified in boxers in the 1920s, and chronic traumatic encephalopathy, a more recent term, are thought to be the same disorder. Chronic traumatic encephalopathy (CTE) has been widely studied. It is recognized in some retired professional or college athletes who played American football and other athletes who have had repetitive head trauma and in some soldiers with brain damage secondary to closed head injuries due to blast trauma.

Pathologically, CTE is characterized by the deposition of hyperphosphorylated tau protein as neurofibrillary tangles, most prominently in the perivascular spaces, cortical sulcal depths, and subpial and periventricular areas.

Symptoms and Signs of CTE

Initial symptoms of chronic traumatic encephalopathy typically include ≥ 1 of the following:

There are two distinct clinical courses:

  • Mood disturbances and behavioral abnormalities develop during young adulthood (eg, during the patient's 30s), and cognitive impairment develops later.

  • Cognitive impairment develops later in life (eg, during the patient's 60s), and mood disturbances and behavioral abnormalities may develop after cognitive impairment.

Diagnosis of CTE

  • Clinical criteria

Criteria for clinical diagnosis of chronic traumatic encephalopathy (CTE) include the following:

  • A history of head trauma

  • Symptoms and signs consistent with CTE

  • Absence of a more likely explanation of clinical findings

These criteria are also used in research.

Results of routine neuroimaging such as CT or MRI are usually normal. Currently, there are no objective, validated in vivo biomarkers of CTE.

A definitive diagnosis of CTE is based on neuropathologic examination during autopsy.

Treatment of CTE

  • Supportive measures

There is no specific treatment for chronic traumatic encephalopathy.

If dementia develops, supportive measures Environmental measures Dementia is chronic, global, usually irreversible deterioration of cognition. Diagnosis is clinical; laboratory and imaging tests are usually used to identify treatable causes. Treatment is... read more , as for other dementias, may help. For example, the environment should be bright, cheerful, and familiar, and it should be designed to reinforce orientation (eg, placement of large clocks and calendars in the room). Measures to ensure patient safety (eg, signal monitoring systems for patients who wander) should be implemented.

End-of-life issues

Because insight and judgment deteriorate in patients with dementia, appointment of a family member, guardian, or lawyer to oversee finances may be necessary. Early in dementia, before the patient is incapacitated, the patient’s wishes about care should be clarified, and financial and legal arrangements (eg, durable power of attorney, durable power of attorney for health care Durable power of attorney for health care Advance directives are legal documents that extend a person's control over health care decisions in the event that the person becomes incapacitated. They are called advance directives because... read more ) should be made. When these documents are signed, the patient’s capacity Capacity (Competence) and Incapacity Historically, “incapacity” was considered primarily a clinical finding, and “incompetency” was considered a legal finding. That distinction, at least in terminology, is no longer firmly recognized... read more should be evaluated, and evaluation results recorded. Decisions about artificial feeding and treatment of acute disorders are best made before the need develops.

Prevention of CTE

Preventive measures are the most important intervention. Because chronic traumatic encephalopathy typically results from repeated head injury, people who have had a concussion Treatment Sports activities are a common cause of concussion, a form of mild traumatic brain injury. Symptoms include loss of consciousness, confusion, memory difficulties, and other signs of brain dysfunction... read more are advised to rest and to gradually return to sports activity. Those who have had several concussions should be advised of the risks of continued play.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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