Sleep to Wake Timing

[tbirdwilson]

I'm six months in to CPAP therapy, and there is a clear trend in my charts: the later I fall asleep, the worse I do in terms of AHI. The earlier I fall asleep, the better.

If I fall asleep between 9-10pm and wake around 4-5am, my numbers are invariably below 5, usually AHI in the 2's. However, if I sleep between 11-12pm-and wake up at 6-7am, I do much worse. Often 5-7 AHI. I wake up more during the night, and tend to have a lot of sleep-wake junk in the last hour or so. I realize REM sleep cycle is a factor in my late night AHI rises (relaxed muscles and jaw drop), but I suspect that my circadian rhythm is better aligned with an early bed to early rise cycle. Once I get past 5am, I think my system just wants to wake me, and thus the SWJ. I don't seem to get as much (or usually any) SWJ on an earlier sleep-wake cycle.

Anecdotal observation. Curious if this has struck anyone else.

[ChicagoGranny]

Anecdotal observation.

... of a correlation, not necessarily causation.

You may be overlooking something:

fall asleep between 9-10pm and wake around 4-5am

...

sleep between 11-12pm-and wake up at 6-7am

What have you done differently during the days when you go to sleep later as compared to what you did during the days when you went to sleep earlier?

[tbirdwilson]

Yeah, obviously I can't control for all of the confounding variables here. But because my life is highly regimented as a graduate student (and I currently drink no alcohol or coffee), the strongest correlation is with the timing of my sleep. Pretty much all other conditions are the same. In any case, pragmatic view says do whatever seems to work.

[Jay Aitchsee]

I think we may have touched on this briefly in your other thread. I think circadian rhythm could play a part in your early waking. In my own case, it doesn't matter what time I go to bed, I wake around 5 AM. My solution was to go to bed earlier, routinely (Good Sleep Hygiene).
There are treatments that attempt to bring the biological clock to a more desirable setting (Google Circadian Rhythm Sleep Disorder or Advanced Sleep Phase Disorder). I have no idea of the success rates of the various treatments. Simply going to bed earlier works for me.

[tbirdwilson]

Interesting. I had never heard of APSD. This sounds just like me. I just can't sleep late. This was definitely not a problem until the last few years, though.