US country music veteran Glen Campbell, famous for hits like \"Rhinestone Cowboy,\" has Alzheimer\'s disease, the singer announced. In an interview with People magazine, the 75-year-old and his wife Kim said they decided to go public because he plans a final series of concerts later this year and wants fans to know his condition. \"Glen is still an awesome guitar player and singer,\" she said. \"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, whose other hits include \"Gentle on my Mind,\" said he has suffered for years from short-term memory loss, but was diagnosed with Alzheimer\'s six months ago. \"I still love making music, and I still love performing for my fans,\" he said, adding: \"I\'d like to thank them for sticking with me through thick and thin.\" An estimated 18 million people worldwide suffer from Alzheimer\'s, the most common form of dementia.