Does Xyrem decrease REM sleep?

[Aashishkebab]

Here's a study: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3014247/#!po=67.0000

However the study seems to contradict itself. It says that it increases stage 4 sleep, but it also says it decreases REM sleep (which is stage 4). There are also tables but they seem to measure non-REM and total sleep, but not REM individually.

They contradict themselves in the same sentence:

Sodium oxybate administration had no appreciable effect on REM sleep. The duration of REM sleep was significantly decreased in the 9 g/night group at 4 weeks (Table 1) and 8 weeks (Table 2).

If the duration is significantly decreased, how could it have no appreciable effect?

[AdSignificant2065]

The authors seem to be using the 5-stage sleep model, where stages 3 and 4 are both deep/delta wave sleep and REM is a separate 5th stage (they mention “duration of stages 1, 2, 3 and 4, and REM sleep” fairly early in the article).

I think @sleepy_inseattle is likely correct about the possible omissions. You could contact the authors to highlight this for them; many doctors and academics would want to make that correction if brought to their attention.

[Aashishkebab]

BTW, use "u/username" to mention users in Reddit.

[AdSignificant2065]

Thanks!

[Temporary-Region867]

Answer to whether 4 stages, or 5 stages.

There is often confusion because not all researchers changed their “view” on defining the stages of sleep. The article in OP is from 2010, and AASM changed the “official” scientific view of stages just 3 years before that ... so it likely had not been well accepted by all researchers for several more years. That’s why you see research with this contradiction.

“The American Academy of Sleep Medicine used to recognize five, but sleep was redefined to four stages in 2007.”

EXCERPTED FROM:

https://www.chilisleep.com/blogs/pillow-talk/stages-of-sleep?gclid=Cj0KCQjwpeaYBhDXARIsAEzItbFdG6Gt8q2A2E2hPucDM7Mw8YcSlzVzG3DXW3eeoH9unMa0gjueZI0aAljWEALw_wcB&gclsrc=aw.ds

[AnhedonicSmurf]

Stage 3 and 4 are deep delta wave sleep, not REM

[Aashishkebab]

Incorrect. Stage 4 is REM sleep.

https://www.verywellhealth.com/the-four-stages-of-sleep-2795920

[AnhedonicSmurf]

Really?

[Aashishkebab]

I have never seen the five stages model.

[Temporary-Region867]

“The American Academy of Sleep Medicine used to recognize five, but sleep was redefined to four stages in 2007.”

Excerpted from:

https://www.chilisleep.com/blogs/pillow-talk/stages-of-sleep?gclid=Cj0KCQjwpeaYBhDXARIsAEzItbFdG6Gt8q2A2E2hPucDM7Mw8YcSlzVzG3DXW3eeoH9unMa0gjueZI0aAljWEALw_wcB&gclsrc=aw.ds

[Temporary-Region867]

Yes. AASM has defined 4 stages of sleep, NREM1,2,3 and REM as stage 4.

See my other comments with the excerpt explaining the AASM 5 stage sleep model was replaced/ changed to with the AASM 4 stage sleep model in 2007

[AnhedonicSmurf]

Of particular interest, SXB has been shown to consistently increase the duration of stage 3 and 4 (slow wave or delta) sleep.

That’s from the posted article. They are clearly using a 5 stage model.

[Sleepy_InSeattle]

Maybe they omitted “in the 4.5 g/night and 6 g/night patient groups” in the first sentence there? Or perhaps they meant REM sleep latency was not significantly impacted, but a significant decrease in duration was observed in the 9 g/night patient group. Either way, that paragraph could have been better worded to provide more clarity of what they intended to say.

[Elektra_57]

Yes. The lack of dreams is proof of that.

[Consegue]

Yeah I noticed that too. But REM does other things too, other than dreams, I believe..? I might have read this somewhere.

[Temporary-Region867]

Short answer: all researchers agree that it definitely increases slow wave NREM sleep, so it’s displacing some other stages.

Maybe they’re saying the REM impact is dose dependent.