The singer, whose "Rhinestone Cowboy" topped the charts in 1975, had been suffering from short-term memory loss in recent years. He was diagnosed with Alzheimer's disease in early 2011.
Alzheimer's disease (AD), also known in medical literature as Alzheimer disease, is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death
The 78-year-old Grammy winner and his wife, Kim, initially shared the news of his illness back in 2011, because he'd hoped to give a series of goodbye concerts in conjunction with an album, Ghost on the Canvas, which was released later that year.
Ghost on the Canvas (Surfdog), Campbell's 61st studio album, was expected to be his last. It wasn't. A brand-new collection of recordings from the legendary singer, See You There, was released last December on the same label. With Campbell's health apparently in decline, it's increasingly likely the collection will be the final studio recording of the Arkansas native's career.
The latest health setback comes just days before the documentary of that final tour, titled Glen Campbell ... I'll Be Me, gets its world premiere April 18 at the 2014 Nashville Film Festival.
Campbell was named both CMA Entertainer and Male Vocalist of the Year in 1968, and was inducted into the Country Music Hall of Fame in 2005. The veteran performer has sold more than 45 million albums over the course of his career.
He went on a final "Goodbye Tour," with three of his children joining him in his backup band; his last show was on November 30, 2012 in Napa, California. Campbell sang "Rhinestone Cowboy" as a goodbye at the 2012 Grammy Awards which was held on February 12, 2012.
Campbell has been married four times and is the father of five sons and three daughters, ranging in year of birth from 1956 to 1986.