Are any of you finding that your partner with early onset Alzheimers falls asleep every day for a few hours even after a 8+ hour sleep?

Probably not dementia. Other things to consider - drinking enough water, thyroid doing OK (low levels = low energy), no infections or allergies, look at medications.

I would let him sleep as KNance says. My Mom napped when she lived in her house. She didn't went she got to mine. I so wish she had slept 4hrs. Would have been some downtime for me.

Lisa Marie A : Evening, make sure he not having Minnie strokes ( TIA)
He's bord around that time . Before falling a sleep take him out for a walk . Nice days . The body is shutting down slowly when not doing anything. Keep him mi d awake. Play cards , shoot Pool go to an active center . Small outting, beside staying in house.
( As my mother use to say those four walls will cave on you .)

Start with was a walk daily or change up route
Respectfully

Let him sleep it is a Blessing .

LisaMarieA: My mother, who did not have dementia, but heart issues exclaimed "Why am I so tired? I slept well. The only thing I've done is make my bed and eat breakfast." Your partner should see his physician to ensure that there's nothing else going on besides the Alzheimer's.

My husband is often sound asleep an hour or two after getting up in the morning, another nap in the afternoon, and an early evening nap. But I don't think this is due to dementia, I think it is because he has heart issues. Perhaps your partner has other health issues that would cause him to sleep more. And honestly, I don't think an evening nap is all that unusual.

My husband slept many hours during the day and night. He would sleep all night, then while sitting in his recliner, that's all he did. He would fall asleep just after breakfast, sleep few hours, wake up, eat lunch, or we would go out for mail, etc., come back, sleep in his recliner, have dinner, or go out, and sleep in his recliner few hours later, I would have to wake him to go to bed. He had Alzheimers.

Yes, happened with my husband and his Alzheimers, slept most of the day, without medication except for his heart, joints, etc.

My grandpa and father would say that they weren’t sleeping. They often said, “I am only resting my eyes.”

I didn’t believe grandpa wasn’t sleeping, until he got upset with my grandma for turning his baseball game off.

When grandma would respond with, “You were sleeping!” He would tell her the score of the game. He was only resting his eyes and wasn’t sleeping.

Personally, it’s not unusual for me to watch just about an entire movie and fall asleep five minutes before it ends. 😁

I do agree with funky about people sleeping more if they are bored or taking certain meds.

Much more sleep, not with dementia, but in normal aging process as well.
More sleep and less food is the norm.

Unfortunately Alzheimer's(especially early onset as that can go on for 20+ years)does not progress quickly like some of the other dementias do, so I doubt it's because of his Alzheimer's that he's sleeping more than usual.
Could it be some of the medications he's on, as many medications can cause sleepiness?
Or it could be that he's just bored, or his brain is just tired from having to work so hard for him to now function.
Any concerns you have should be addressed with his doctor as they will know him better then we do.

A lot of people fall asleep on the couch or in their chair, even without dementia.

Ask his doctor what he/she feels about this, since you are concerned about him sleeping so much.

Did he nap occasionally before having dementia?

Best wishes to you and your husband.