Effect of Humidifier on AHIs?

I recently discovered the heated humidifier on my S8 Auto II is not working, meaning it is essentially functioning as a pass over humidifier. Although I suspect this has been the case for awhile, I have noted my AI and AHI readings have been higher lately than usual, sometimes dramatically (e.g., my usual AI reading is around 1, lately it has ranged from 1.5 to 4.0, averaging maybe 1.8 ).

Initially, I thought perhaps the higher readings were the result of having sprained my back, and the effect that might have on my comfort during sleep, and ultimately my breathing patterns. However, now that I have confirmed the humidifier problem, I am wondering if there is anything out there to suggest a heated humidifier somehow contributes to effective therapy in the sense of affecting the AI and AHI numbers. I suspect the answer is it does not, but thought I'd raise it in case anyone has information on this.

Heated humidity is a comfort thing and shoud not really affect therapy except that some people don't sleep as well without some heated humidity so, I guess it does affect therapy to an extent.

I live in Canada and only use pass over humidity from April to November. In the months in between (winter) I sleep better with a humidity setting of 1 or 2.

Your AHI is not really too bad.

I usually have an AHI of under 1, but at the moment, I am having a few problems with my Rheumatoid Arthritis and my AHI is higher some nights if I am in more pain. I don't actually wake up fully but I am not reaching deeper sleep levels as often.

What I am saying is that you may be right about your back. Are you on medication for it? If you are, that may be influencing your therapy more than the lack of heated humidity.

Thanks for the response. I should note, however, what I posted was my AI, not AHI. My AHI is running in the 7 to 10 range, which even with the S8 II is probably too high. And although my back has been aching quite a bit the last few days, I haven't been taking any medication (but probably should be taking something like Advil).

Sorry I misread that! You're right, even on a Resmed machine that is maybe high for your AHI, although your AI is not too bad. I don't know a lot about Resmed but some say that you should half your number of hypopneas for an AHI that it comparable to a Respironics machine's AHI. Resmeds count hypopneas differently. This would make your AHI within a good range.

I am thinking that you might get better rest and better therapy, if you did take some pain meds for your back if it is aching quite a bit, as you said. I take a Tylenol Arthritis every night at bedtime and it sure helps with better rest most nights.

Trying some pain meds may give you an indication of whether or not heated humidity would make any difference for you.

Jay K,

I feel that my numbers are affected by humidity. How ironic, my humidifier stopped working last night and my numbers showed it. I had a horrible day too which I'm sure was due to my crappy sleep last night. What humidifier do you have? I have a H4i but the machine sees H3i and it doesn't give me the option to change it. I'm going to talk to my DME tomorrow about this.


Jeff

Jeff,

I also have I have a H4i and my S8 Auto II also sees it as H3i. I believe I read somewhere this is normal although if you hear otherwise please let us know. What is not normal though is the water does not heat up even though the green light does go on as it is supposed to.

I would be real interested in what your DME says.

Jay

This question interests me as well:

Jay K wrote:I am wondering if there is anything out there to suggest a heated humidifier somehow contributes to effective therapy in the sense of affecting the AI and AHI numbers. I suspect the answer is it does not, but thought I'd raise it in case anyone has information on this.

If the tissues in the throat are more moistened by humidified air, are they less likely to collapse together, or, if they do collapse, are they more easily moved apart by the air splint?

I'd be interested in hearing the perspective of others on this basic, yet complicated question.

If the tissues in the throat are more moistened by humidified air, are they less likely to collapse together, or, if they do collapse, are they more easily moved apart by the air splint?

Unfortunately many people view heated CPAP humidifiers as something akin to to steam saunas. They are not. They are only designed to provide enough moisture to bring the air in the system up to normal room humidity levels (40 to 60%).

If the user is mouthbreathing for extended times, even 60% relative humidity is not enough to keep the mouth moist. The CPAP humidifiers are not designed to keep the mouth moist. Users who crank the setting up due to dry mouth, are not able to resolve the dry mouth and are causing other problems, such as rainout and possibly nasal congestion.

Design a device that can get steam into the throat and you may see some improvement in AHI.

Jay K wrote:I also have I have a H4i and my S8 Auto II also sees it as H3i.

FWIW, Elite II's also show H4i's as H3i. I am pretty sure that the ResScan software does as well.

rooster wrote:

If the tissues in the throat are more moistened by humidified air, are they less likely to collapse together, or, if they do collapse, are they more easily moved apart by the air splint?

Unfortunately many people view heated CPAP humidifiers as something akin to to steam saunas. They are not. They are only designed to provide enough moisture to bring the air in the system up to normal room humidity levels (40 to 60%).

If the user is mouthbreathing for extended times, even 60% relative humidity is not enough to keep the mouth moist. The CPAP humidifiers are not designed to keep the mouth moist. Users who crank the setting up due to dry mouth, are not able to resolve the dry mouth and are causing other problems, such as rainout and possibly nasal congestion.

Design a device that can get steam into the throat and you may see some improvement in AHI.

This is so true! I am a mouth breather, and there are days that I wake up with my mouth so dry. My DME company made sure to tell me 5 times that heated humidity is NOT part of the treatment, it is for comfort only. When I travel for short periods, I don't even bring my humidifier, my machine fits easier without. I don't notice a huge difference for the day of two without it.

It's been my experience that modest changes in humidity level can have a definite effect on nasal tissues and therefore on breathing; some of us clearly do better with less humidity, while others do better with more. Your back problem does present a confound that could easily affect your AHI, and it's quite possible that your increase in AHI is due to both your back and the lack of humidification. Hope you feel better soon.

I believe that the humidity can have an affect on AHI. My feeling is based on anecdotal evidence. I find I do better with passover or no humidification in the summer but need heated humidification in the winter. I am also wondering what setting you are using on your H4i. I find that if I use a setting of 1, there does not appear to be any heat. A setting of 2 does warm the water. A setting of 3 gives me mild rainout (room temperature 62F with a snuggle hose cover). I use 2 and it works perfectly fine. I would love to see a machine development where you can set a relative humidity level instead of a blind heat setting.