Not even young amateur athletes are safe from chronic traumatic encephalopathy (CTE), an Alzheimer’s-like disease resulting from repeated head trauma, according to a new study from Boston University. CTE has long been linked to professional football, among other impact-driven sports. But BU’s research discovered more than 60 cases of CTE in athletes who were under 30 years old at the time of their death. In fact, the researchers determined that 63 of the 152 donated brains they studied—about 40%—had already developed early signs of CTE. Researchers also believe they’ve diagnosed the first American female athlete with the disease. CTE, which can only be fully diagnosed post-mortem via autopsy, can cause memory loss, confusion, aggression, depression and other memory and mental health issues. Past studies have mainly examined the prevalence of the disease among professional football players, but this one from BU is the first to prove on a large-scale that the risk of CTE is still high among amateur and youth athletes.