'The Price Is Right' Host Bob Barker's Cause of Death Revealed

The beloved TV personality died on Aug. 26. He was 99.

Bob Barker's cause of death was Alzheimer's Disease. ET obtained the late The Price Is Right host's death certificate, which confirmed the cause of Barker's death on Aug. 26 at age 99.

"Up until several months before his passing, Bob Barker routinely participated in conversation and bedside exercises," Nancy Burnet, Barker's girlfriend of 40 years, tell ET.

TMZ was first to report the news of Barker's cause of death

Last month in a statement to ET, Barker's longtime publicist, Roger Neal, said, "It is with profound sadness that we announce that the World's Greatest MC who ever lived, Bob Barker, has left us."

Neal also said that, per Barker's request, there will be no funeral or memorial service held in his honor. He'll be laid to rest next to his wife, Dorothy Jo, at Forest Lawn Memorial Cemetery in the Hollywood Hills. Jo died in 1981.

Later, in an interview with ET, Neal revealed that Barker died in his sleep at his Los Angeles home. Neal also praised Burnet for how she took care of the late TV personality in his final years.

"I can't stress enough the great care that Nancy took of him. It was around the clock," Neal told ET. "The fact that he got to stay in his home -- the same house since the 1950s -- to be able to live there his whole adult life and be able to be at home when he passed, I think it was very fortunate."

"The last five years of his life she was completely devoted to making sure that his healthcare, that his care on a daily, around-the-clock basis, was the top," he added. "In my opinion, [Nancy] is a saint for having done that. I don't think anybody could have done the job she's done. I think she was the absolute best person to take care of him."

As for how Barker will be remembered, Neal said, "He lived a wonderful life and he helped mankind and animal kind and he left this planet a much better place than he found it."

"I think he leaves a legacy from television that will not be matched, will not be duplicated. I think he leaves a legacy for the animals. I think if animals could talk they would all be applauding Bob Barker today," he shared. "... I think he's one of those people who took that platform that he had, the celebrity that he had, and used it for absolute good to make the world a better place. I think the world is a much better place having had Bob Barker in it."