CTE: What we know and what we need to learn

In this Nov. 4, 2010, file photo, Philadelphia Flyers' Jody Shelley, left, and New York Rangers' Derek Boogaard fight during an NHL hockey game in Philadelphia. Boogaard suffered from chronic traumatic encephalopathy, a degenerative brain ailment related to Alzheimer's disease that is caused by repeated blows to the head, the New York Times reported. The 28-year-old Boogaard, who died in May of an accidental overdose of alcohol and oxycodone, was found to have had CTE _ which can be diagnosed only after the death of the patient, according to the third story of an extensive three-part series on Boogaard posted on the newspaper's website Monday night, Dec. 5, 2011. (AP Photo/Matt Slocum, File)

Last week doctors announced that Junior Seau, the former San Diego Chargers all-pro who took his own life in May, has joined the ever growing list of former NFL players with CTE. Before football ends for the season, there should be a discussion of CTE and its association with concussion. 

CTE stands for Chronic Traumatic Encephalopathy. It is believed to be an environmentally caused form of dementia due to its link with head trauma and sports. CTE is a progressive and degenerative disease of the brain caused by repeated trauma to the brain. In the brain, concussive and sub-concussive blows to the head, leads to progressive degeneration of brain tissue and production of a protein called tau, which has been implicated as having a major role in CTE’s presentation due to its accumulation in the brain tissue interfering with brain function. 

These changes can occur several months to years even after the last hit to the brain. NFL players are not the only victims of this disease. It has been found in other athletes such as boxers, rugby players and professional wrestlers. Combat soldiers have also been diagnosed with CTE.  Some notable athletes who have been diagnosed with CTE include former Eagle Andre Waters and the Pittsburgh Steelers Mike Webster as well as former New York Ranger Derek Boogaard.

Patients with CTE generally go through three stages of the disease.

Stage 1: The patient has affective (mood) disturbances or psychotic manifestations. 

Stage 2: The second stage is characterized by social instability, erratic behavior, memory loss and the beginning symptoms of Parkinson’s disease. 

Stage 3: In the final stage of the disease, the patient has later stage symptoms of Parkinson’s disease, speech, gait and balance abnormalities, difficulty with speech and swallowing, and drooping of the eyelids. 

Diagnosis is generally made via patient history and post mortem examination of the patient’s brain. As such, there is no test to detect CTE and there is currently no known cure or consensus on treatment. The Center for the Study of Traumatic Encephalopathy in Boston is currently performing post-mortem examinations of several brains of former athletes, including many NFL players, to get a better understanding of this condition to hopefully develop treatment paradigms and an eventual cure.

At this time, unfortunately, we do not know the answers to several questions as to the link between concussion and CTE. We do not know how many hits it takes to lead to CTE to develop. We also do not know whether the severity of the hit plays a role, or if there is a specific location in the brain the hit has to occur to cause CTE. We do not know how long one has to be in a certain sport to be vulnerable or how long an athlete may be out of contact sports before CTE develops. Finally, we do not know if there is any kind of genetic predisposition to CTE.  Until these questions are answered, it is imperative that any athlete that is suspected of having a concussion is removed from play until seen by a physician with special understanding of concussion for accurate diagnosis and treatment.