My mother-in-law is 85, has no sensation of needing to go, or of being wet. Will wear depends, but does not have sensation of wet, urge to go. Refuses to believe that she has wet herself, saying that she must have sat in something wet. She will wear adult diapers, but forgets to change them and leaks. The doctor has said that there is nothing he can give her if she doesn't even have the sensation. She is very stubborn and becomes very agitated if her smell or wetness is pointed out to her. She even hangs up dirty clothes to wear again.
She has no short term memory or focus, but is otherwise healthy.
I have yet to try a potty schedule. I would like a schedule but I'm not sure how often I should get her to go to avoid accidents. She used to have diarrhea accidents all the time until the doctor cut her diabetic medicine to half the original dosage. Once doctor put her on a low dose anxiety pill, not only did it stop her panic attacks, it also caused her glucose reading to drop! Little did we know that her anxiety was spiking her sugar levels. Now that she's so much calmer, most other things are better with my mom!
Finally, my mom doesn't get diapers via medicaid or medicare or the supplemental insurance either. I used to buy them at Walmart until I was told I could buy them at the local Flea Market at a greatly reduced price. It's true! So it might be worth your time and effort (and pocket book) to visit your local flea market for adult diapers.