Dramatic differences in AHI after returning from vacation

[russmac]

Last night my AHI was .46, which for me is amazing. It makes me wonder what causes the variations. When I bought this machine a month ago, I was on Christmas vacation in Utah. After the first 4 nights my AHI numbers started bouncing around and at one point went up to almost 21. I couldn't see any obvious reasons for the variations. We returned to North Carolina on January 12, and from that point, the AHI numbers have stayed under 3.13, and are generally around 1.8.

There are 5 things I can think of that might be factors:
1. Elevation - It was around 5000 feet in Utah, and it's closer to 500 feet in North Carolina
2. Humidity - I'm not sure what the specific differences are during winter, but I would think the climate control would compensate. I use about the same amount of water each night.
3. Bed - The bed in Utah seemed comfortable. It was quite a bit softer
4. Pillows - The pillows in Utah seemed comfortable enough, but I was happy to get home to my own pillows.
5. Room temperature - The room we stayed in was fairly cold, about 65 degrees F. At home the room is more like 72 degrees.

I have no idea what caused the difference, but was surprised, and happy, that things are so much more stable at home.

[ChicagoGranny]

There are 5 things I can think of that might be factors:
1. Elevation - It was around 5000 feet in Utah, and it's closer to 500 feet in North Carolina
2. Humidity - I'm not sure what the specific differences are during winter, but I would think the climate control would compensate. I use about the same amount of water each night.
3. Bed - The bed in Utah seemed comfortable. It was quite a bit softer
4. Pillows - The pillows in Utah seemed comfortable enough, but I was happy to get home to my own pillows.
5. Room temperature - The room we stayed in was fairly cold, about 65 degrees F. At home the room is more like 72 degrees.

#6 - On vacation, you ate more and you ate later.
#7 - You drank more.
#8 - You were under more stress.
#9 - Mormons give you jimmy legs.

[OkyDoky]

I think many times vacations are stressfull and not as relaxing as we wanted. Always planning and going. It did look like your sleep was a little more fragmented. So maybe the difference is just HOME SWEET HOME.

[GettingBetter]

Last night my AHI was .46, which for me is amazing. It makes me wonder what causes the variations. When I bought this machine a month ago, I was on Christmas vacation in Utah. After the first 4 nights my AHI numbers started bouncing around and at one point went up to almost 21. I couldn't see any obvious reasons for the variations. We returned to North Carolina on January 12, and from that point, the AHI numbers have stayed under 3.13, and are generally around 1.8.

There are 5 things I can think of that might be factors:
1. Elevation - It was around 5000 feet in Utah, and it's closer to 500 feet in North Carolina
2. Humidity - I'm not sure what the specific differences are during winter, but I would think the climate control would compensate. I use about the same amount of water each night.
3. Bed - The bed in Utah seemed comfortable. It was quite a bit softer
4. Pillows - The pillows in Utah seemed comfortable enough, but I was happy to get home to my own pillows.
5. Room temperature - The room we stayed in was fairly cold, about 65 degrees F. At home the room is more like 72 degrees.

I have no idea what caused the difference, but was surprised, and happy, that things are so much more stable at home.

Higher elevations can increase central apnea events.
http://www.ncbi.nlm.nih.gov/pubmed/23429871

Also, I love North Carolina - the food, the shore, the people - maybe that had something to do with it too!

[russmac]

LOL

I actually weighed less when I got home, though I did eat plenty. I never drink, unless you are talking about water intake, which I think was about the same. I was working remotely for the week before I returned home, which does correspond to significantly higher numbers. It doesn't account for the stress after I got home. I was in a house full of mormons in Utah, and some of them (my wife and kids) followed me back to NC, so I'm pretty sure that's not it.

I do think the comfort of being home has to have something to do with it.

[russmac]

Higher elevations can increase central apnea events.
http://www.ncbi.nlm.nih.gov/pubmed/23429871

Also, I love North Carolina - the food, the shore, the people - maybe that had something to do with it too!

Thanks for the link! Elevation is what I suspected the most since it was the biggest overall change.

We really like North Carolina. The weather (except for snow days like today) is usually gorgeous, and we do enjoy our trips to the beach. Definitely good people and good food.

[jonny515]

People who live at a higher elevation have O2 levels. I'm in Albuquerque and had to get used to the altitude (which is similar to Denver at 5500 ft) I wonder also re: average no. of apneas of people in high altitude areas, but have no idea about it.

[IDontSnoreISwear]

Hubby and I live at sea level. When we spent the summer out west, he had to change his CPAP pressure from 8 to 10 or 11 depending on elevation. (Wish I had done the same but I was not yet on CPAP -- which could be why I felt like such shit while out there!)

[herefishy]

The modern cpap machines are supposed to be self adjusting for altitude.

[jagzoo]

Change in altitude might be detrimental for some (seems like it might make sense) but not everyone - it doesn't seem to affect me, at least not in the short term. I spent about 2 months in Colorado and Utah this past Spring, much of the time over 7000 - 8000 ft., and my AHI and pressure needs didn't change (AHI averages <.5 with a pressure of 10.5). Maybe my machine just works well?

[VVV]

Change in altitude might be detrimental for some (seems like it might make sense) but not everyone - it doesn't seem to affect me, at least not in the short term. I spent about 2 months in Colorado and Utah this past Spring, much of the time over 7000 - 8000 ft., and my AHI and pressure needs didn't change (AHI averages <.5 with a pressure of 10.5). Maybe my machine just works well?

This is not a useful post since you don't say at what altitude you normally reside. Maybe your full time home is at 10,000 feet?

Here is a small study of the effect of altitude change and central apnea - http://www.aasmnet.org/jcsm/ViewAbstract.aspx?pid=28368

[Chevie]

Maybe my machine just works well?

ResMed machines have been tested by the manufacturer to maintain the set pressure up to 8500 feet altitude.

[jagzoo]

Sorry - More info:

I live on a hill and my home is at 710 ft altitude. I'm a "flat lander". We drove directly West with little or no time for acclimation.

My APAP that I was using at the time was the Respironics 560. Part of the time we were "off grid" and I powered it by a solar powered battery.

[palerider]

The modern cpap machines are supposed to be self adjusting for altitude.

+1

their internal pressure sensors, which they use to calculate how fast to spin the blower to generate a desired pressure work against ambient, not absolute pressure, therefore, it doesn't matter to them, in the least, what altitude you're at, as long as there's enough air that the internal fan can grab to create the desired pressure.

the higher up you get, of course, the faster the fan has to spin to generate a desired pressure, and at some point (typically spec'd around 10000 feet) there's not enough air for it to be able to stay within it's operating parameters... (or maybe the pressure sensors don't work too well much above that, I haven't ever looked at the spec sheets).

at any rate, the manufacturers have to pick some cutoff and say "we know it'll work up to this point, beyond that, we ain't sayin"

[russmac]

Thanks for all the replies. It's possible that the machine adjusts to altitude, but I do not. It's just amazing to me that my stats are so obviously different from the date of my return. It's all for the better, so I'm not complaining.