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OTRC: Glen Campbell opens up about battle with Alzheimer's disease

Glen Campbell appears in a 2008 promotional photo, released as part of his 'Meet Glen Campbell' album publicity campaign. (facebook.com/glencampbellofficial)

Glen Campbell, a 75-year-old country and pop singer known for the 1975 hit "Rhinestone Cowboy," has opened up about his battle with Alzheimer's disease.

In his first TV interview since he announced to fans that he was diagnosed with Alzheimer's disease two months ago, Campbell told Terry Moran on Tuesday's "World News with Diane Sawyer" that he sometimes forgets what he's talking about in the middle of a sentence.

"I'm going to be right in the middle of a sentence, man - and it just goes, pew," Campbell said. "I haven't felt it yet. I've always been forgetful anyway. I'm only what, 78?"

"75," his wife of 30-years, Kim Woollen corrected during the interview, which took place in the couple's Malibu home. Campbell said he sometimes dependent on his wife to help fill in the blanks of his memory.

"I just take care of him, which is a big job," Woollen said. "We'd been noticing short term memory loss for quite some time. You know, he repeats himself -- tells the same joke several times in a row. He'll tell a joke, laugh at it and a few minutes later tell the same joke, laugh, and then we laugh at him because he's just enjoying it so much ? You just make the best of each day and try not to worry about tomorrow."

"Definitely take care of what's today and tomorrow's going to have what it has," Campbell said."There's a verse in the bible that says, 'If the man findeth a good wife he's found a good thing,' and I found a good thing, or she found me. Did you find me or did I find you?"

"I think we found each other," Woollen said.

"That's what we did. Amen," Campbell agreed.

Campbell was diagnosed with Alzheimer's disease eight months ago after suffering from short-term memory loss for years. In June, the couple made the decision to tell fans about the diagnosis and announced the singer's final tour.

"Glen is still an awesome guitar player and singer," Woollen told People magazine. "But if he flubs a lyric or gets confused on stage, I wouldn't want people to think, 'What's the matter with him? Is he drunk?'"

"I still love making music," Campbell added. "And I still love performing for my fans. I'd like to thank them for sticking with me through thick and thin."

The couple decided to go public with Campbell's diagnosis "because he's hoping to say farewell with a final slate of live performances this fall - and they want his fans to be aware of the musician's condition," People said.

The singer has released more than 60 albums through his career. Aside from "Rhinestone Cowboy," he has ruled the charts with songs such as "Bloodline" in 1976 and "Southern Nights" in 1977. Campbell last released new music of his own about three years ago.

Scientists have not yet determined what causes Alzheimer's disease, which brings about memory problems, hallucinations, delusions and paranoia. It has been said that genetic, environmental, and lifestyle factors all play a part, according to the National Institute of Aging.

There has been no concrete evidence that substance abuse leads to Alzheimer's disease, although a 2010 U.S. study published in the International Journal of Geriatric Psychiatry suggested that people who possessed a certain protein in their body and had a history of heavy drinking or smoking were likely to be diagnosed with it nearly 10 years earlier than those with none of the risk factors.

Like many musicians, Campbell battled drug and alcohol problems for years. He said on the CNN show "Larry King Live" in 2002 that he overcame his addictions by turning to God, adding: "I just woke up and said, I can quit this. I know I can, and like I said, I prayed and I prayed. And cigarettes went. I stopped smoking. And the liquor came later. And, like, all within a span of three or four weeks. I just clean cut everything."

After he became sober, Campbell married his fourth wife Kim, a former Radio City Musical Hall dancer, in 1982. They are parents to Cal, Shannon and Ashley. The three provide backing vocals on the singer's 2008 album "Meet Glen Campbell," as do two of his other five children from previous relationships.

Watch Glen Campbell's "World News with Diane Sawyer" appearance below.

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