It might seem rude and just pilling on someone who is already down, but from personal experience and from talking with nurses who deal with palliative care and care of elderly patients, a major indicator of whether the patient will improve or not has to do with how much they actually do for themselves.
My own grandfather for example was hospitalized for a few weeks after being blinded in 1 eye. For the first 2 weeks he continuously got worse, not because of his original injury, but because of the lack of motivation direction and drive. Eventually when my father noticed his nurses were cutting his food and feeding him, he put a stop to that with a "why are they doing that for you? You still got hands, so use them". It hadn't even occurred my grandfather that he could do it himself.