More events sleeping on side than on my back. Any explanation?

[Asjb]

In my diagnostic test, I had 90 obstructive apnoeas + hypopnoeas per hour sleeping on my left side, which was more than when sleeping on my back (81/hr). Right side was only 25/hr.

I thought that sleeping on one's back was always much worse for obstructive SA?

The only theoretical explanations I can think of are a large and late meal (which I didn't have) or perhaps a hiatus hernia with the stomach pressing up into the chest. I have no symptoms of that.

Have other people had worse results on their left side, and any ideas why?

[OpalRose]

Interesting, because I also have worse results sleeping on my left side than on my back.

I do sleep side to side, and end up on my back because of hip pain, but when on my back, I notice I need higher pressure...not by much, but it does rise and takes care of any apnea events that occur because I'm on my back. That is the beauty of an APAP machine.

Eating late at night causes my AHI to rise also.

[MURACKD]

I have sleep apnea on my back of 57 times per hour and I have 0 on my side. I am told this is a little uncommon

[justMongo]

For some people, sleep apnea is not positional.
Statically speaking, 90 per hour is close enough to 81 (referring to the OP) that one may infer that Asjb's apnea is non-positional.

As for me. My auto machine is effective when I sleep on my back and when I sleep on my side.
Sleeping on my back will result in hitting my upper pressure limit.

Making a generality, usually people do better side sleeping.

[Sleeprider]

The classic sign of positional apnea, is stubborn clusters of OA that do not go away with significant increases on pressure. You will see them on the forum sometimes. Most people with APAP may see pressure changes through the night as flow limitation and snores change with body position and sleep stage. Others with CPAP need to maintain higher pressure for the 'worst case' position. True positional apnea may not respond to any normal CPAP pressure, and those are the ones that need to get off their backs. If that's not your, then sleep well in whatever position you feel best.

[Asjb]

Hello. Thanks to all for replying.

justMongo wrote <Statistically speaking, 90 per hour is close enough to 81 that one may infer that Asjb's apnea is non-positional> and <My auto machine is effective when I sleep on my back and when I sleep on my side. Sleeping on my back will result in hitting my upper pressure limit>

Agree with your statistical comment but how can one explain that my diagnostic AHI sleeping on my right side was only 25/hr? Why might there be such a difference between the two side-sleeping positions? My fatigue seems to be extremely sensitive to my AHI on treatment as I only have good daytime energy when I have an AHI of less than 1/hr (and I have analysed this <blind> i.e. scored my daytime energy for a week at a time then afterwards looked at the AHI results). So if the influence of position seen during my diagnostic test also holds true during treatment nights, perhaps it would be a good idea if I can try to train myself to spend most of each night lying on my right-hand side.

And justMongo how do you know when you are sleeping on your back? - do you video yourself when asleep or use some sort of 'sleeping position' app?

Sleeprider wrote: <The classic sign of positional apnea, is stubborn clusters of OA that do not go away with significant increases on pressure…..True positional apnea may not respond to any normal CPAP pressure, and those are the ones that need to get off their backs. If that's not your, then sleep well in whatever position you feel best>.

Thank you, that's really interesting - I hadn't read about that before.

And OpalRose wrote: <Interesting, because I also have worse results sleeping on my left side than on my back>

So what could we have in common that gives us that? (just curious)

[OpalRose]

Asjb
Don't know what we might have in common with left side sleeping.

I can't say I was ever comfortable with left side sleeping, but had read somewhere that this position was best if you experienced digestive problems, which I do.

I started to make a mental note what time it was when sleeping on my left side, then checked my graphs and noticed more events during that time period. Of course, we cant always know how we are sleeping, and I'm not going to video tape myself.

I can sleep on my back with no increase in apnea events, but my 90% pressure will go up. I've decided that comfort comes first, and let the APAP do its thing.

Good luck in figuring it out.

[richb]

I have sleep apnea on my back of 57 times per hour and I have 0 on my side. I am told this is a little uncommon

People are often encouraged to spend some time sleeping on their backs during sleep studies because there is a much higher probability of OA events. I recently had some minor surgery and spent the night in the hospital. I couldn't sleep because of stimulants I was given to raise my BP. My room mate told me he had severe OSA. He was given a machine to use while he was staying in the hospital. He used it for about an hour and then turned it off when the mask started leaking. He went back to sleep on his side. No snoring, no choking, no sudden waking up, just quiet steady breathing. Then he turned on his back. Lots of snoring and choking sounds. He then went back to sleep on his side and again quiet. I told him in the AM that he could probably sew a tennis ball into the back of his t-shirt and give up his machine. He also said his machine at home had a good mask and he could use it all night. His wife said she would fix him a t-shirt with a tennis ball.

RichB

[archangle]

There's just so much variation from person to person that it's hard to draw conclusions.

You may position your head or neck differently on your side. Your brain and nervous system are also involved, so they might do something different. Muscles and muscle tone may change, etc.

The tongue falling back as you sleep on your back is an obvious explanation for worse apnea on your back, but not everyone behaves the same way.