Terrible and complicating. "A number of things wrong with them", seemed to be a common theme when I had the chance to politely enquire when talking with older people that were in the hospital for eye treatment at the same time as me. Just the eyes is bad enough, it must be tough having to deal with a bunch of overlapping health concerns, seeing doctors regularly, taking all the meds, etc.
If someone is overweight, the complications seems a given when reaching a certain age. There's no doubt a lot out of one's control, like heredity, but it did occur that trying to take good care of yourself should start at a young age. Things like diabetes and high blood pressure lead to other diseases. Gout seems quite common these days, whatever the reason. Diet and how much you consume must be big on health. Kidney dialysis must not be fun. I know some folks that spend a good part of their week being slaves to that for as long as they will live.