The 76-year-old former linebacker, one of the leaders of the Dolphins' undefeated 1972 Super Bowl championship team, suffers from memory loss, cannot use his left hand and struggles to put on a shirt, among other ailments.
Buoniconti would not say he suffers from CTE, according to the report, but his doctors have confirmed there are brain issues that might be linked to playing 14 years of professional football.
His story is expected to bring more attention to the NFL's longstanding battle with former players concerning head trauma and its potential effects from playing football.
"We're the players who have built the game, but have been forgotten," Buoniconti told Sports Illustrated in an article published Tuesday. "The [concussion] settlement is a joke; the way it is structured is a joke. They are waiting for us to die. They're going to play the clock until everybody dies."
The article detailed one instance when Buoniconti fell backward down a flight of stairs, which caused him to bleed, and told his wife, "I should just kill myself! It doesn't matter!"
According to his son Marc, who was paralyzed while playing football, Buoniconti is "frustrated" and "depressed."
The Hall of Famer estimates that he took about 520,000 blows to the head while playing football. MRIs over the past two years have revealed brain shrinkage, according to the report.
Nick Buoniconti played seven years for the Dolphins and was an eight-time Pro Bowler and two-time Super Bowl champion. He also played seven years for the Boston Patriots and had a successful post-football career in broadcasting and business.
After his son's 1985 injury, Buoniconti was a driving force behind the Miami Project to Cure Paralysis, raising hundreds of millions of dollars for research.
At age 55, Buoniconti said he felt normal. But 21 years later, that is no longer the case.
"I didn't have any idea the price would be this debilitating," Buoniconti told Sports Illustrated. "Had I known, would I have played? I had no alternative; there was no other way for me to get a college education.
"Football kept rewarding me -- I can't deny that. But I'm paying the price. Everybody pays the piper."