A recent study published in the New England Journal of medicine revealed that brain scans of more than two dozen former NFL players found that the men had abnormal levels of the protein linked to chronic traumatic encephalopathy (C.T.E.), the degenerative brain disease we have discussed here that’s associated with repeated hits to the head.
THE TESTING
Researchers were on the hunt for the presence of tau, an abnormal protein that’s an indicator of CTE. They utilized position emission tomography (PET) scans using a radioactive drug called flortaucipir to detect elevated amounts of tau protein.
They imaged 26 living former football players and compared them with the brains of 31 people with no history of traumatic brain injury. The players studied were males between the ages of 40 and 69 had played in the NFL for at least two years and a minimum of 12 years of tackle football. They compared the football players’ brains with the brains of 31 individuals with no history of traumatic brain injury.
THE RESULTS
It came as no surprise to researchers that the brains of the former players revealed more tau deposits than those of the people who hadn’t had a brain injury. Most importantly, the scans detected tau in the same regions where tau has posthumously been found in CTE-diseased brains. The study authors stressed that tau imaging is not conclusive or exclusive in diagnosing CTE and we are still years away from a true diagnostic test. Other markers could include blood and spinal fluid. However, this is a positive step in the right direction. Prior to this imaging, pathologists have only been able to confirm a diagnosis on the deceased by identifying the presence of tau in donated brains.
CTE DIAGNOSIS HISTORY
CTE was first discovered during an autopsy of the brain of former Pittsburgh Steelers center Mike Webster after his death in 2002. Seventeen years have passed since that discovery and in that time over 100 former NFL players have been diagnosed with neurodegenerative disease. They aren’t the only ones who have been diagnosed since the spotlight shined on this disease. The awareness of damage from repeated concussion and head trauma has been linked to other athletes, military veterans, and victims of abuse.
A PEEK INSIDE THE BRAIN
There have been previous studies that utilized other tracers to detect the tau protein, but these materials weren’t able to differentiate tau from beta amyloid, the protein that signifies Alzheimer’s disease. Flortaucipir is much more specific in being able to pinpoint tau.
Doctors and scientists have come to believe that CTE is the result of repeated head trauma. This can occur in football, not just from hard hits to the head that lead to concussion, but from repeated rattling of the brain inside the skull that occurs during routine tackles. These repeated hits are known as subconcussive hits and can result in a buildup of tau.
When proteins clump around small blood vessels in the valley of the cortex, CTE develops. Then, the protein begins to spread, destroying other parts of the brain. CTE is irreversible and there is no cure. 
CTE is a neurodegenerative disease that results in Alzheimer’s-like symptoms, which include mood swings, memory loss and impulsive behavior. The progression of the disease can lead to paranoia, dementia and suicidal thoughts.
LOOKING TO THE FUTURE
In spite of the small number of players examined, scientists believe the new findings could have long-term implications. This is the first step and will lead to important discussions about diagnostic and treatment options for patients suffering from traumatic brain injuries.
They note that there are still many questions to be answered regarding CTE, especially surrounding why the disease is more severe is some patients than others and why it develops at all. There is much work to be done. Thankfully, there’s an army of scientists on the ground furiously working to further advancements in all areas of CTE, TBI, dementia and Alzheimer’s disease.
Source:
https://www.nejm.org/doi/full/10.1056/NEJMoa1900757?query=featured_home