Elderly person with moderate dementia was napping but stopped...Any thoughts?

Is it “moderate dementia” or “undiagnosed dementia”? Undiagnosed dementia is no dementia at all. It is merely a guess. What makes you think he has dementia? What are his symptoms? If he hasn't been screened for dementia, and you think he has dementia, have him screened by his doctor. Dementia is not even a diagnosis. Having dementia is like having a headache... it is merely a symptom(s). The cause of the symptoms has to be determined. So before you try to figure out his change in sleeping pattern, find out what you're dealing with. In other words, if he does have dementia, find out why?

How is his anxiety level?

My mother couldn’t sleep when she was anxious.

A year later, and deeper into the dementia, she naps all the time.

excitement of xmas?

hopefully he suddenly stopped napping for good reasons. maybe he’s suddenly interested in some things?

the napping sometimes comes from boredom.

pre-xmas hugs to you and your father :) !!