Experiences for Alzheimer's patients in the last months/year before life comes to end. What were your experiences like?

I am going to take the last part first. What causes their death if they are healthy?
The body begins to shut down. As the need for food decreases she will stop eating. Little things happen before this. Parts of the body "forget" how to work properly. This is when Aspiration comes in and how Aspiration Pneumonia develops.
The body conserves energy and blood circulation becomes poor. (This is why they are often cold) The body will maintain best circulation keeping the major organs supplied with blood and oxygen. Heart, Lungs, Brain. These eventually shutdown as well causing death. Lots of stuff happens in between.
Sleeping a lot is a sign of decline. Having increases secretions because swallowing is difficult.
I strongly suggest that you contact Hospice and they will help you a lot with the What's happening, Why is it happening, What can you do, What can you expect.
Hospice will provide you with all the supplies, Equipment and Support you will need. I would not have been able to care for my Husband the way I did if it had not been for Hospice. He was on Hospice for almost 3 years.
((hugs))

Considering all the activities you say your mother is partaking in aside from sleeping, I'd say she is declining cognitively more than she's dying.

My mother slept for about 18 hours a day. She'd get up in the morning, eat breakfast, take a nap in her chair, have lunch, sleep in the chair until dinner, then stay awake to watch TV for a couple of hours (endless reruns of shows she'd seen 100 times already), then go to bed and sleep for nine hours straight.

I think a large part of that sleeping was due to boredom and a failing ability to process what was going on around her. She had dementia, was very hard of hearing, and had macular degeneration, so the signals coming into her brain were already scrambled by her sight and hearing. I think it was a lot to process, and it was making less and less sense to her all the time.

That was about six years ago, and she only died last week.

I will say this, though -- she was at home with just my dad who had his hands full taking care of a large house and doing all the cooking and shopping as well as trying not to lose his own identity caring for Mom. He ended up dying first (three years ago), and after I move Mom to a memory care facility, the endless sleeping stopped. She wasn't allowed to just sit in a dark room all day and was brought out into the common room to be with the other residents. She wasn't required to participate in the activities, but just being around others did perk her up quite a bit. Social interaction is so vital for those with dementias, and it's terribly difficult to carry that load on your own. My dad really tried, but my mother refused to go anywhere with him. I don't know that my dad ever really realized she had dementia. I know I didn't until after he was gone.

The sleeping when someone is dying isn't like regular sleeping. It's more like a toy that's just winding down. My mother was "asleep" for the most part for the last three days of her life. She didn't open her eyes anymore, but she would eat a little bit if the nurses used a syringe to feed her. She'd grip my hand tightly when I held it, but after a while I realized it was more of a reflex than anything else. She'd mutter something here and there, but it was clear she was turning inward and the fact that we were there no longer registered.

All her life she'd twirl a lock of her hair habitually, and even in her "sleep" those last few days she'd reach up to her hair. The last day of her life, it was like she was literally winding down. Her hand started up, but it stopped about halfway to her head. I twirled her hair for her, and put her hand back down in her lap. The next morning she was gone. It was all very peaceful.

That's more what dying looks like.

I am currently reading a book that I am going to recommend to you: With the End in Mind by Kathryn Mannix. Read a free preview. I think you will like it (and I think you need it.)

I’m in the same boat as you right now. My mom is at the tail end of stage 6 and at some point in the last couple of months has started sleeping A LOT. I’m talking 17-20 hours a day. She’s awake for meals and that’s pretty much it. She’ll turn on the tv and get into the recliner…and then promptly fall asleep. She became semi-incontinent around the same time period. Other than Alzheimer’s, she’s very healthy. I’ve been wondering myself if this is the beginning of the end.

You have some helpful advice here. It is true that people with dementia do sleep more as the dementia progresses. However, there is research that suggests this enables them to deal better with the plaques and tangles in the brain. The sleep does not remove the plaques or tangles or confusions, but it lessens them and helps those with dementia to relate. My wife was sleeping 18 to 19 hours out of 24 but still relating well for more than two years in this situation, even as my daughter and I were feeding her. She often thanked us and smiled and lived at peace until her death in June at the age of 84 after 58 years of our marriage.

I agree with several others that what is happening is gradual cognitive decline, not end of life. Do get help from a care agency such as Home Instead Senior Care. If you try to do everything yourself, you will at some point burn out. It's better to give yourself space both to be with and to be without the loved one for whom you are caring.

Take care. Give care. with my prayers

@OneBlueMoon, I sent you a private message.

Naminda only provides temporary results, and later becomes ineffective. Personally, I would have my mom only take essential medications per her doctor.

My Mom is the same way. waking up exhausts her.
Walking in the backyard for a little while (gotta check the raspberries for fruit) exhausts her. Sitting in her chair...exhausts her. If she's up for 2 hours...time for a nap....
She's gone from a 10pm bedtime, to an 8pm bedtime, and now is having a 6pm bedtime. I wake her after 3 hours so she can go to the bathroom but mostly she just sleeps. And she does it quite well.
She would like to die. She's ready but I don't think her body is actually in an active death cycle, yet. So...she sleeps.
It's been this way for a while but the last 6 months has increased the sleeping.

I am new to hospice and will say more...but to assure you, no one needs to be hospitalized to become a patient in hospice. In most cases I believe you can keep your own MD as well, who will be kept up to speed or can handle medication changes as needed. In my mom's case she has dementia, mixed type. It has not been possible to get her to a routine visit to her primary care, though he has been kept informed and had the records from the former MD with whom he worked. At one point he said he would do whatever he could to help. Well, the one night mom suddenly decided she would or could not go upstairs to bed and spent the night sleeping on the carpeted steps and/or floor with a blanket/pillow...in the AM we called the squad to help get her up and they encouraged getting her checked out at local hospital. Hospice had been called earlier in the week, but they could not make it official and provide care until/unless MD signed off. Family medicine doc refused because he had not seen her in so long, and so it turned out to be the ER doc who signed off. I hesitate to share my hospice opinion, but that's what this forum is for right? SO let me tell you it has been both a blessing and a curse to me. THe expectation/burden on family is more than I anticipated (laundry, being available for home visits etc); the aides have been at times disappointing though the nurses have been great. THe hospice assigned MD which we agreed to, was unassigned after I learned about both competing hospital systems having home care MD programs. Hospice MD had prescribed imo inappropriately an anti-psychotic drug with potential for serious side effects. This was for some combative/agitated behavior she had when 2 strangers (the aides) did not keep her adequately covered and proceeded to clean her personal areas. To medicate her with an inappropriate IMO drug for those brief times was just WRONG. SO we now have another MD in charge. Hospice can provide resources you might otherwise have challenges to find. WE couldn't do it without them, but it is some work...what with laundry generated along....just beware, ask questions....and to add re the sleeping, that I haven't had much experience but have known of one case where the spouse slept probably about 22 out of 24 hours....it was a gentle passing....at home....