(Reprinted from CNN News)

A new study from Boston University’s CTE Center has discovered more than 60 cases of chronic traumatic encephalopathy, known as CTE, in athletes who were under the age of 30 at the time of their death. This is the largest study to look at the neurodegenerative disease in young people.

Researchers found about 40 percent of the brains studied had developed some of the earliest signs of the disease, which is associated with repeated head trauma. The study also includes what researchers believe to be the first case of an American female athlete diagnosed with the disease.

The report, published in JAMA Neurology on Monday, describes the features of 152 brains donated between February 1, 2008, and September 31, 2022, to the UNITE brain bank — the largest tissue repository in the world focused on traumatic brain injury and CTE. Sixty-three out of the 152 donated brains (41 percent) had autopsy-confirmed CTE.

The disease can only be formally diagnosed with an autopsy and has been associated with memory loss, confusion, impulse control problems, aggression, depression, impaired judgment and suicidal behavior.

Unlike past studies, which looked at CTE primarily among professional American football players, the majority of the athletes diagnosed in this study were amateur athletes who played at the youth, high school, and college levels.

“This study clearly shows that the pathology of CTE starts early,” said Dr. Ann McKee, coauthor of the study and director of the Boston University CTE Center. “The fact that over 40 percent of young contact and collision sport athletes in the UNITE brain bank have CTE is remarkable,” adding that community brain bank studies show that fewer than 1 percent of the general population has CTE.

McKee also notes that all the brains included in the study were donated for a reason. “[The study] is not a general population study. It’s not a prevalence study,” she said. “We get brain donors who are very symptomatic, and that’s why the family pursues brain donation.”

CTE is an Alzheimer’s-like disease that has been most commonly associated with former professional football players, but has also been detected in military veterans, including many who have been exposed to roadside bombs and other types of military blasts. Previous studies have shown that repetitive hits to the head — even without concussion — can result in CTE.

Most of the donors analyzed in this recent study played football (60 percent), followed by soccer (15 percent) and ice hockey (10 percent). Other sports included in the study that resulted in CTE diagnosis are amateur wrestling, rugby and professional wrestling.

The donors’ ages at the time of death ranged from 13 to 29 years old. The youngest person diagnosed with CTE in the study was a 17-year-old high school football player, McKee told CNN.

Brain donors who died before they reached 30 were selected to minimize any contribution from age-related conditions, the study authors said.