AHI going up - raise pressure?

[ladyhen]

Just curious. My AHI is still seriously low, it's just that it's gone up and I'm wondering if it's due to weight gain or what?

I was always around 0.3-0.6 and am now running 1.2-1.8. I have a autopap with my settings at 7-20. I'm thinking of increasing my minimum to 9 and seeing if that does anything.

Thoughts?

[johnthomasmacdonald]

my ahi has been in the high teens, low 20s for 6 weeks on auto apap as set by the MD at 4-20, raising it myself to 10-20 lowered it to 7.5, the last two nights i used it as cpap rather than apap and it was 3.5 at 14 and 2.5 at 13.5. tonight i'll go down to 13 ( i'll keep dropping till it goes up)

[Pugsy]

That difference is insignificant and doesn't really warrant a change but you could try it if you wish.

That said...anyone who is thinking about adjusting pressures needs to understand what they are trying to fix.
Make sure that the AHI is mostly obstructive in nature before evaluating possible pressure changes.
You need to evaluate the event categories separately.
Clear airway (central) events aren't treated with pressure increases with cpap/apap machines. If the bulk of the AHI is central in nature no amount of pressure increases will fix it and might make it worse.

We consider pressure increases when the obstructive component of the AHI is higher than we want and the obstructive component is made up of the hyponeas and the obstructive apneas.

So make sure you are trying to limit something that has the potential to respond to pressure. Centrals will not because the airway is already open.

[Xney]

Those numbers are still very low, I don't think you need to, unless you start feeling tired or something regularly.

That being said, I would look at the data from your machine. If you see it spending a lot of time at 9-10 rather than 7-8, then maybe it makes sense because it's doing it anyways. (especially if there's events at the lower pressures)

Raising pressures can result in centrals for some people, something to consider.

[SuzyFor2]

I appreciate Pugsy's response. Central apnea can actually get worse with CPAP treatment, especially at first. My doc told me that some people's brains become habituated to less O2 so when they start getting enough O2 at first their brains respond paradoxically......as they have less obstructive sleep apnea, they have more central sleep apnea but then that evens out. An AHI of 5 or less is considered a good result, though, and many people never achieve it.

[Todzo]

Just curious. My AHI is still seriously low, it's just that it's gone up and I'm wondering if it's due to weight gain or what?

I was always around 0.3-0.6 and am now running 1.2-1.8. I have a autopap with my settings at 7-20. I'm thinking of increasing my minimum to 9 and seeing if that does anything.

Thoughts?

Hi ladyhen!

How about the change of the seasons? I look at stress (most important!), how much I exercised, how, what, and when I ate, how much sleep I have been getting, the trend of weight. There are may things in our life that contribute or detract from our having AHI. But over the years the transition in fall has been the most likely to raise AHI. Perhaps part of it is our bodies actions to get ready to produce more heat - perhaps changes in the airway passage breathing the colder air (it got down to 32 degrees Farenheight where I live!).

I agree with others, your changes probably do not warrent a pressure change at this time. Try a bit more exercise, sleep, and possibley a sauna. Once the air got warmer in the house my breathing improved and that is likely to help with AHI.

Today I look for some good liver. Super source of vitamin A and seems to help with the Fall transition,

Have a lot of fun!

Todzo

[Pugsy]

A word about centrals and higher pressures and the fear of higher pressures causing more centrals.
There are a few people who do seem to have centrals pop up with cpap therapy that didn't have them prior to cpap therapy.
It can happen at any pressure and it is not limited to "higher" pressures. It can just as easily happen with a pressure of 7 cm. It is not nearly as common as people tend to think.
A very small percentage of people who start cpap therapy will have this happen. Higher pressure don't automatically equal centrals.
I use an auto adjusting machine (first APAP and now BiLevel) with minimum pressure around 10 and my max at 20. I saw a max pressure of 19.61 reported the other night and I had zero centrals that night.

So when increasing pressures it is something to keep an eye on but it doesn't happen nearly as commonly as people seem to think. There are people using straight cpap pressures of 20 cm and they don't have any more centrals than anyone else.
A few here and there are normal anyway.