Naps vs. Nights

OwlCreekObserver · Post by **OwlCreekObserver** » Wed Nov 01, 2006 2:52 pm

I don't think I've seen this issue covered previously.

Retired old coot that I am, I sometimes drop off for a nap during the afternoon. I nearly always use my CPAP gear during those delightful little timeouts for grownups.

However, my AHI is always much higher for those times than I get at night. It's the same bed, same machine, same mask, same pressure, etc., but the numbers are way off and I sometimes feel really lousy after the nap.

Yesterday was a good example. I dropped off for a 45 minute nap. When I checked the numbers, they revealed: OA: 16.5, H: 1.8, VS: 0 = AHI: 20.3.

This morning I checked my numbers from last night: OA: 3.9, H: 1.0, VS: 0.1 = AHI: 5.0

As I said earlier, the conditions are pretty much the same in the afternoon as at night.

Has anyone else ever noticed this? Any thoughts as to what might be the cause?

OCO

cflame1 · Post by **cflame1** » Wed Nov 01, 2006 4:57 pm

my naps usually tend to be better than my nights... but yes i do notice a difference when i nap.

Snoredog · Post by **Snoredog** » Wed Nov 01, 2006 5:45 pm

probably the same thing happens during the first 45-minutes when you sleep at night, but you have several cycles after that so you don't notice it.

I say if you can take a nap take it, but I wouldn't let a daytime nap influence my night time sleep.

I read one theory that if you wake up during deep sleep you feel worse or unrefreshed than if you were woke during REM.

If you look at the cycles we go through during the night you see you spend more and more time in REM as morning or wakeup time approaches:

This also seems to run in parallel with papers I've read on melatonin levels as we progress through the night (melatonin levels peak at about 2AM and taper off towards morning).

SelfSeeker · Post by **SelfSeeker** » Wed Nov 01, 2006 6:00 pm

Hello OwlCreekObserver,

I noticed that the nap AHI was double the night one or more. (Some times the same.)

I thought it may be that I am very tired so the throat relaxes causing more events.

Offerocker · Post by **Offerocker** » Wed Nov 01, 2006 6:11 pm

THANK YOU, SNOREDOG, for a very interesting post!

IF I'm interpreting the graph correctly, it seems to reflect why sometimes we "seem" to get sufficient recharging after only four hours?

Snoredog wrote:
I read one theory that if you wake up during deep sleep you feel worse or unrefreshed than if you were woke during REM.

I believe that happened to me last Friday; my husband woke me (after not enough sleep), and I could hardly stand without leaning on a wall, even after some coffee. I was like a zombie, and couldn't shake it. Went back to bed - for hours. I've never felt THAT bad before, but must agree that, after several years of being able to awake when my body chooses to, I'm NOT as alert when awakened by external means.

I'm curious now, because it seems that my 'naps' are around two hours! I'm certainly not a 'power napper'.

Do different people have different 'cycles'? And I'd only assume that there are other factors in this? It is very interesting. More information, or references welcomed here!

Snoredog wrote: If you look at the cycles we go through during the night you see you spend more and more time in REM as morning or wakeup time approaches:
<snip>
This also seems to run in parallel with papers I've read on melatonin levels as we progress through the night (melatonin levels peak at about 2AM and taper off towards morning).

Thanks for some very interesting food for thought - and investigation.

snoozie_suzy · Post by **snoozie_suzy** » Wed Nov 01, 2006 7:42 pm

OwlCreek,

One thought I was pondering... what was your REM latency on your sleep study? Did you get into REM phase in an avg time ? 90 mins or under? If so maybe during these naps you are getting into REM quickly, and where most peoples' apnea is worse during these stages than the other sleep phases perhaps it increases your AHI percentage vs. the resp. events that Encore pro scores during your 8 hour sleep data? I mean if the Apnea/Hypop/ Flow limitations occur in a small cluster and the person has only slept like 60 to 90 minutes vs. the amount they might get over the course of the night when they cycle thru the different phases, then divided by the sleep time the ratio would be less?

I am truly not a mathmetician, so this statement could be completely inaccurate, but was just pondering.

Suzy

krousseau · Post by **krousseau** » Wed Nov 01, 2006 10:34 pm

OCO how long do you usually nap? Wish I could remember where I read naps should be limited to less than 30 min max. It was an apnea episode during a nap that alerted me to OSA, beside being told I breathed "funny" when sleeping.

Snoredog · Post by **Snoredog** » Wed Nov 01, 2006 10:42 pm

Offerocker wrote:

Do different people have different 'cycles'? And I'd only assume that there are other factors in this? It is very interesting. More information, or references welcomed here!

That graph is only a representation of what we may go through, not everyone follows that exact sequential pattern of sleep, you can go from Stage2 to REM or Stage2 to Deep (Stages 3&4).

I've read where you should only nap for 20-minutes if you want to feel refreshed so you don't go into REM but I don't know if that is true or not, I don't nap. I used to nap before cpap, in fact many times that was the only way I got any restorative effects from sleep at all was from a nap.

OwlCreekObserver · Post by **OwlCreekObserver** » Thu Nov 02, 2006 4:35 am

Thanks to everyone for your comments. I've wondered about this for quite some time now.

If apnea events are more common during deep sleep, then I suspect that I often drop into it fairly quickly after I fall asleep. I've noticed that the events are often clustered during the night, which could mean that I just have a higher percentage of them during the much shorter nap.

My naps normally range anywhere from 15 or 20 minutes to an hour or so. The average is probably 30-45 minutes.

I should probably stop taking naps altogether because I've been recently waking up VERY early in the mornings, unable to go back to sleep. This morning was about 3:00 AM. I'd like to blame the daylight savings nonsense, but it's probably a combination of things (home sale, moving, season change, etc.). I'm hopeful things will return to [what passes for] normal before too much longer.

Thanks again for the comments and suggestions.

OCO

bsil · Post by **bsil** » Thu Nov 02, 2006 4:54 pm

OCO-
Just a thought, perhaps it has to do with whatever morning medications you may take. For example, if you took an antihistamine (some can cause drowsiness and then perhaps more relaxation of neck muscles)each morning, this may account for a higher nap AHI. Most of it has worn off by bedtime and thus lower AHI.

Like I said, Just a thought!
Barb

bsil · Post by **bsil** » Thu Nov 02, 2006 4:55 pm

Hey OCO-
My son has applied to the U of I...are you anywhere near there?

OwlCreekObserver · Post by **OwlCreekObserver** » Thu Nov 02, 2006 7:39 pm

bsil wrote:Hey OCO-
My son has applied to the U of I...are you anywhere near there?

Yep, just a few miles down the road. I proudly waive the orange and blue of Illinois but I must confess that I bleed the scarlet and grey of Ohio State, especially when they play each other in football as they are doing this Saturday.

OCO

bsil · Post by **bsil** » Thu Nov 02, 2006 9:21 pm

Did you work at the University before you retired ? My family is orange and blue from way back...the '70s !