Wow, being in your late 60s is a tough age to be. I recently turned 67, so I'm watching these events kind of closely
. After David Bowie died, and his family revealed very little of the cause of death, I found myself worrying what got him, and, should I be worried.
David Bowie - died at 69 years, 1½ years after getting diagnosed with what is said to be liver cancer (wikipedia).
Alan Rickman - died of pancreatic cancer also at age 69. He was diagnosed only last August.
Glen Frey - died at 67 after a long history of rheumatoid arthritis and acute ulcerative colitis. Both RA and colitis are auto-immune diseases, probably related to each other. Frey apparently had severe cases of these for quite a few years.
I can't say I was a big fan of any of them, but I've known about them for a long time. And it's impossible to ignore their ages.