DENVER (KDVR) — Seven months after former Bronco Demaryius Thomas died, doctors who studied his brain say the wide receiver suffered from stage 2 CTE, or chronic traumatic encephalopathy.

The family of Thomas made the announcement Tuesday along with the Concussion Legacy Foundation. They said they hope to raise awareness.

A release from the Concussion Legacy Foundation says, “In the years before he died, Thomas developed depression, anxiety, panic attacks, and trouble with his memory.”

Thomas’ mother, Katina Smith said in the statement, “He was just so young, and it was horrible to see him struggle. His father and I hope all families learn the risks of playing football.”

Dr. Ira Chang, the director of neurocritical care at Swedish Medical Center in Englewood said these are typical symptoms.

Chang has no connection to Thomas but has treated others with CTE.

“The brain is affected and not functioning as well from repeated, chronic trauma,” Chang said.

“It does raise a lot of questions about what does that mean for a lot of different professional athletes,” she said about the diagnosis.

Chang says athletes need to follow strict protocols and safety measures because preventing head injury is the key.

“There’s no way to regenerate brain cells as an adult and so you have to be very careful to try to do as much preventatively as you can,” Chang said.

Thomas’ cause of death has not yet been reported, but his family said he suffered from seizures after a car accident.

It is possible he was dealing with two different issues.

The Concussion Legacy Foundation said in the release, “Although late-stage CTE can be associated with epilepsy, it is far more likely that he developed post-traumatic epilepsy after a motor vehicle accident and fall he experienced several years before his death.”