Yes, esp. thanks to the mandatory sentencing laws; more ppl will be serving longer sentences.
I think prison medical staff would reccommend treatment for anything anyone on the outside would have reccommended. A lot is currently spent on psychiatric treatment, incl psychiatric drugs! And I don't see that part changing any time soon.
My friend is a corrections officer in a juvenile prison (12-21) and he has to take them to a big university Hospital when they need procedures too complicated to be done onsite. He says they have a lot of weird ailments -- peeing in two streams instead of one, hemmorhaged rectums (sodomizing one another), swallowing contraband, ingesting their own excrement, malnutrition from refusing to eat and pica...
I would imagine it gets worse as the inmates get older. Lots of them (adults have serious psychiatric issues and HIV).