Dialysis - yes or no for an elderly patient with diabetes?

My grandmother, who is 86 years old, has been told by her specialist that she should start thinking about whether she wants to pursue dialysis treatment or not. Because of diabetes, she is rapidly reaching the point at which her kidneys will fail completely and so the option was presented to her. Now I've seen many case studies and reports stating that those with comorbid diseases (like diabetes, anemia, ischemic heart disease, etc.) don't have a significant improvement on dialysis and that to put elderly people on this treatment is a drain on the economy and not worth the trouble. On the other hand, there are quite a few who have stated that with innovations in dialysis and delivery as well as proper maintenance of comorbid diseases, many symptoms can be improved and that good quality of life can be maintained on dialysis even in these patients. I'm curious if anybody can offer some more insight into dialysis for elderly people with diseases or point to some more literature on the subject. Thanks.