The First Baseball Player Diagnosed With Chronic Traumatic Brain Injury

Ryan Freel committed suicide after a career marked by blows to the head.

Ryan Freel makes a diving catch on a fly ball on August 7, 2006. (John Sommers II/Reuters)

In his six years with the Cincinnati Reds, Ryan Freel wowed fans with his ostentatious, fearless style, running into walls and colliding with other players. He estimated that he had sustained 10 concussions in his career, though his family said the number might have been even higher.

But off the field, he struggled with depression and substance abuse. His repeated injuries led him to retire from baseball early in 2010. One year ago, Freel, then 36, killed himself with a shotgun.

Today, he’s become the first Major League Baseball player to be diagnosed with chronic traumatic encephalopathy, or CTE, after researchers at the Boston University School of Medicine released the results of a test on his brain tissue after his death.

CNN’s Stephanie Smith and Dan Moriarty explain that Freel’s brain was in the moderate stage of the degenerative disease, which has recently become better-known for its possible connection to brain damage and suicides in former pro football players:

Testing of his brain tissue after death … found that he had Stage 2 CTE, which is associated with erratic behavior and memory loss. Stage 4, the worst possible expression of the disease, is associated with full-blown dementia, aggression and paranoia.

The brain tissue of people found to have CTE displays an abnormal build-up of tau—a protein that, when it spills out of cells, can choke off, or disable, neural pathways controlling things like memory, judgment and fear.

The diagnosis of several NFL players with CTE has sparked widespread debate over the future of football. But Freel’s case is interesting because it suggests that the disease can afflict even players of less-aggressive sports.

Brain (top) and microscope images (bottom) showing
progressively severe tau protein deposits. (Boston University)

"I cringe when I see two guys going after the same ball," Robert Stern, co-founder of the Center for the Study of Traumatic Encephalopathy at BU, told CNN. "Is baseball as significant a concussion sport compared to others? No. Is it a concussion sport? Yes."

MLB representatives have said that they are working to prevent further head injuries among players, including instituting a ban on home plate collisions that could start as early as 2014.

Freel’s life and death may also focus greater attention on the significance of all sports-related head traumas, even those that don’t cause concussions. A study of 159 concussion-free college athletes published last week in Neurology found that 20 percent of the contact-sport players and 11 percent of the noncontact athletes performed worse on a memory test at the end of the season than at the beginning, a decline that would otherwise be expected in less than 7 percent of a normal population. The study authors also found that those who did worse on the test had more extensive changes in their brains than those who had scored the same after the season was over.

And an animal study published last week in Biological Psychiatry found that when concussions do occur, they can cause brain cells to become excessively inflammatory, leading to depression later in life. This season, 18 MLB players were removed from the roster after suffering concussions.

Until recently, CTE could only be definitively diagnosed after death, making it hard for researchers to know just how many head traumas is too many, or even how CTE in former professional athletes relates to their mental health issues.

Stern, the BU psychologist, emphasized that, "Whether or not the disease was the cause of or accentuated the depression and substance abuse and impulse problems (Freel had), we don't know.”