The 34-year-old Haynesworth also told Nashville radio station 104.5 The Zone and ESPN's Paul Kuharsky on Thursday that he deals with memory loss issues.
"Nobody really knows: I almost died," Haynesworth told the radio show while attending the Ohio Valley Conference women's basketball tournament at Municipal Auditorium. "I had two brain aneurysms that were nearly rupturing. I went and talked to my doctor in Florida, and he was like, 'Man, your blood pressure is through the roof. I'm going to admit you.' They did a lot of tests and found the aneurysm that was rupturing at that point."
Haynesworth said surgery resulted in an 11-day stay in intensive care at a Fort Lauderdale hospital.
"I've been OK. It's really hard to remember, and I'm not saying that just because of the concussion thing," Haynesworth said, referring to former NFL players suffering from the effects of head trauma. "A lot of things, I just can't remember. I don't feel as sharp as I used to as far as problem-solving and answering questions and things.
"It sounds crazy, but sometimes, writing my own name, I kind of forget the signature of how I normally write. Or sending long texts, my words get backwards. It's crazy, but hopefully as time goes on, I get better."
Haynesworth was a 2002 first-round selection out of the University of Tennessee and played his first seven seasons with the Titans, recording 24 sacks.
Haynesworth turned consecutive selections as a first-team All-Pro player into a free-agent jackpot, signing with the Redskins on a seven-year, $100 million deal in 2009.
After being a free-agent bust in Washington, Haynesworth finished his 10-year career in 2011 following short stints with the New England Patriots and Tampa Bay Buccaneers. He had 347 career tackles and 30.5 sacks in 123 games.