Is it normal for a patient with Dementia to sleep more and more as time goes on?

I think so.

Sleep is one of the bodily functions that dementia can really mess up -- some kinds of dementia more than others. There may be episodes where the patient doesn't seem to sleep at all for days on end.

If you feel your loved one's sleep patterns are questionable, discuss it with the doctor.

I noticed as we age we tend to nod off a lot. There are times when I on this website and might myself fighting to keep my eyes opened B)

I would assume with any type of illness and the meds given, that would also add to the mix making us sleep more and more.

My mother did but she'd had parkinsons for 15 years and many strokes so the meds for those issues may have had something to do with it. She passed away a few weeks ago at age 89, in no pain, just faded away in her sleep.