A question for those of you sleep specialists out there.  I was looking over my sleep study report, and was looking at the graph that shows the different stages of sleep.  They were listed on the graph in this order:

Movement
Wake
REM
Stage 1
Stage 2
Stage 3
Stage 4

Being unfamiliar with sleep patterns, I had expected REM to be towards the bottom as it seems that moving down the graph progressed into deeper sleep.  I always figured REM was the deepest level of sleep.  Also, I noticed that I was woken up by the tech during REM which I guess could just be coincidence, but since I only had two periods of REM during my study, it would have been nice if she'd have let me finish that one :)  But maybe that's how they do it.  Anybody have any insight?

The following is a quote from the Wikipedia website which has a great description about the sleep stages.  Below it is a link to that website which gives much more information.

Quote:

Sleep proceeds in cycles of REM and the four stages of NREM, the order normally being:

stages 1 > 2 > 3 > 4 > 3 > 2 > REM.
In humans this cycle is on average 90 to 110 minutes,[2] with a greater amount of stages 3 and 4 early in the night and more REM later in the night.

Click here for link to Wikipedia webpage

I don't know all that much about sleep, but I don't think REM is necessarily the deepest stage of sleep, it's just different, in my opinion.  And as the website says, "each phase may have a distinct physiological function."  REM sleep is a small percentage of the overall sleep cycle, but that doesn't mean it's less important.  

And yes, it would have been better if the sleep tech had let you finish the second REM.  I don't know how long it took for you to fall asleep or how long you slept, but I'm guessing that would be a factor in how often you cycle through the different stages.  Also, if you have sleep apnea, very likely your sleep stages are quite different.  But yes, the data would have been better with more of the REM.  But it's more important to complete as much of the REM episodes when being titrated, perhaps more important than the baseline study where they test you without cpap first.  With titration, they need to know what pressure will stop the apneas in all stages.  Still, it's important to know the nature of REM in the baseline, because some people have a higher AHI during REM (everyone's different).  

But then again, sleep techs, who work 12 hour shifts, are anxious to get out of there in the morning and may be quick to get the patients up a little too early.  As the Wikipedia says, more REM occurs later in the night or towards the end of the sleep period.  

The most important thing is the overall data of your report... how bad is your apnea, your blood oxygen levels, etc.  


Linda


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My SO2 dropped to 84% at the lowest.  Oddly, I had no apneas during REM.  My AHI was 59.2 and that was entirely during NREM.  But I didn't sleep real well, so my REM could be worse on a normal night.  I'm terrible at sleeping during sleep studies (based on the 2 that I've done).  Somebody will have to do some pretty tough convincing to get me to ever do another one again without Ambian.

So are you thinking that you personally experienced REM before the other stages of sleep?  doesn't the report clarify this?  I've read that when REM occurs at the beginning of the sleep cycle, instead of the end, it is indicative of narcolepsy.  Do you fall asleep suddenly during the day?  

I've also read that REM is actually a light sleep, and people are more easily aroused by sounds during it---similar to stage 2.  I've also read that alot of apnea occurs during stages 3 & 4 and that's why those people experience less sleep during those stages.  ( In my son's case he skipped stage 3 & 4 but had NO apnea during them....I'm still trying to figure that one out!)

No, I do not go into REM before other stages.  I was just pointing out the structure of the graph on a sleep report.  The "y-axis" shows the stages of sleep, and it seems to indicate that REM is a very light stage.  Just like what you said you read.  That confused me because I had always thought of REM as a very deep stage of sleep.

I only go on assumptions (which aren't at all scientific).

During REM we are actually paralyzed, kept immobile through hormones or something, apparently to keep us from acting out our dreams.  This is not so in other stages.  In fact, other sleep disorders such as night terrors or sleep walking or sleep eating occur during the delta sleep (i.e., Stages 3).  I look at our sleep structure set up as survival mode.  The REM dream state is important for something (noone really understands it), but in order for this state, we are put in a vulnerable situation.  We are animals, so if we're in REM in a place where there are preditors bigger than us which look at us for a meal, then being in this REM state is dangerous.   I feel that evolution has made sure our REM state is short in comparison with our other sleep stages.  In those other sleep stages we can be more easily aroused by stimulus .... therefore better able to run for the hills when that lion comes after us!
 

Ok, that's not at all scientific.

hmmm...I'm starting to wonder something....

since I have been so sure my son has apnea, but very little showed up on the sleep study (all during REM) and no stage 3 & 4 sleep was noted..................

do you think maybe he ususally DOES have stage 3-4 sleep and that is when his apnea occurs?

that maybe he didn't have those deep sleep stages because of the study disturbing him?

but, how would I get around that?  is there a way to monitor ---- say using an "apnea monitor" like infants use, to see if more apnea shows up at home????

I do declare, I think that's a good idea, but what do you think?

raymart43 wrote:

No, I do not go into REM before other stages.  I was just pointing out the structure of the graph on a sleep report.  The "y-axis" shows the stages of sleep, and it seems to indicate that REM is a very light stage.  Just like what you said you read.  That confused me because I had always thought of REM as a very deep stage of sleep.

I think it is OK to post this link, it's a non-profit website: http://www.helpguide.org/life/sleeping.htm

Scroll about halfway down and see the chart illustrating the stages of sleep.  In this graph, unlike others I've seen (including my own sleep study graphs) this one shows the REM at the top but not as a Y-axis category, simply because in a normal sleep cycle one does not pass through REM after initially falling asleep...  

It could be your study graphs are showing something similar, only REM is listed in the Y-axis but the techs all know you didn't pass through it initially?  Just a guess and another non-scientific one at that

Blessings,
--pseudonym