After several months of fairly calm nights, my husband has started growling, yelling, jerking, swinging his arms, etc. in the night. Any ideas?

My father did exactly the same thing. We saw a sleep specialist. It is called REM Sleep Disorder. The thrashing and hitting episodes are night terrors. The worst part was when he would be half asleep and half awake. He would take whatever he was dreaming and merge it with real life. At one point, he thought I was holding him hostage for five hours. He walked, talked and conversed like someone wide awake. This can be dangerous. I finally got him to lay down. When he woke up, he remembered nothing.
The sleep specialist gave him 1 MG of Lorazepam nightly and he has not had a sleep episode since. It has unfortunately developed into Lewey Body dementia and/or "sundowners".
I don't think REM disorder always turns into LBD, but I am not positive. I have known of children with REM Sleep Disorder. I hope this helps.

Has anyone suggested that the type of dementia your husband has might be Lewy Body?

A sleep disorder known as RBD (REM Behavior Disorder) is strongly associated with Lewy Body Dementia (including Parkinson's Disease with Dementia). In this disorder the switch that normally keeps of still when we sleep is not functioning. So when the sleeper dreams he is being chased, his legs run in bed. When he strikes out at the bad guys his fists connects with the dresser or perhaps his bedmate's forehead.

In addition to having a broken "quiet" button, people with this disorder have dreams with repetitive themes. They are often running or fighting with animals or bad guys.

RBD may occur long before dementia appears (even decades, as it did with my husband) or sometime after the dementia does.

Other characteristics of LBD include
1) considerable fluctuation in cognition. Sometimes the thinking is normal or near-normal and other times (perhaps even on the same day) it is highly confused and impaired.
2) Hallucinations, especially in the early stages
3) Impaired depth perception
4) Inability to smell anything
5) Parkinson-like physical symptoms

If any of these sound familiar you might want to read more on LBD. One of the best sources is the Lewy Body Dementia Association website, LBDA.org

I really am not trying to diagnose your husband! But IF it turns out the sleep problem is RBD, it is very easily treatable, and that would be a good thing to find out! Also, if it turned out he has LBD, his doctors might want to adjust his treatment plan.

In any case, any change in symptoms in a person with dementia should be discussed with his doctor. I sincerely hope you find some good solutions!

They are called night terrors, you can google that, my husband AD does the same thing & me & two pups have been recipients of the hits also. We went through his psyche Dr & they actually do not wake up but are reliving a horrific event, in our case he was physically hurt by a health tech in a VA hospital and strapped down. The frequency has come down over this past year, but I know when it's starting as do my dogs they get off the bed and I quickly put a center barracaid up of pillows whatever is close - it does not last long and usually one episode on any given night. His sleep pills are trazadone & seriquel - changing doses does not stop the night terrors as the meds are doing their job and not causing the outburst. They are very scary but as I said they have really tapered & id say it's been two weeks since an episode.

Alexander, I just read back through some of your other posts and it looks to me like these night time problems have been going on for a while. It may be that the dementia is progressing and he needs an additional med for these symptoms. But do keep a log and call the doctor to discuss.

Have you called his doctor to report this change? That's the first thing I'd do.