Glen Campbell has revealed his diagnosis with Alzheimer's disease to People magazine. Campbell, 75, and wife Kim have gone public prior to his farewell tour this fall. "Glen is still an awesome guitar player and singer," Kim told the publication. "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?'" Campbell was diagnosed six months ago, although he had been suffering from short-term memory loss for years, according to the People story. Campbell was inducted into the Country Music Hall of Fame in 2005. His hits include "By the Time I Get to Phoenix," "Gentle on My Mind," "Rhinestone Cowboy," "Galveston" and "Wichita Lineman."