My Mum 76 has been in care since July 16. Physically ( apart from Chronic Lymphocytic Leukemia) she is still well. Very mobile apart from a stiff knee now and again. Cognitively scored 47/100 on ACE 111 and she has almost zero short term memory but then you can be amazed at what she does remember.
However she will no longer sleep through the day, not even a snooze in an armchair, goes to bed about 7/8pm and will be up by 3/4am. I'm not sure how well she sleeps in those hours but the carers do night checks and they have a mattress & door alarm to let them know if they are out of bed. Her Care Home are very resistant to any drug, sleeping or otherwise mainly due to fall risks and would rather manage wandering, agitation, best they can. Sometimes though and because of her Leukemia you can see she desperately needs a good sleep