AHI Total AI Centra AI

[ejbpesca]

In lay terms, could someone please tell me what the following means? Please, no acronyms.

Set to display six months, my Resmed Airsense 10 shows on its sleep report the following:

AHI 1.1
Total AI 0.8
Central AI 0.3

What does each individual term and its number mean? (definition)
By apnea standards are these good or bad scores?
Do these scores indicate my machine is working?
Do these scores indicate anything about my level of apnea? (low, med. high?)

A single day report may show AHI 0.3, Total AI 0.3, Central AI 0.3

[Pugsy]

What does each individual term and its number mean? (definition)

http://sleepyhead.sourceforge.net/wiki/ ... r_Glossary

By apnea standards are these good or bad scores?

very good

Do these scores indicate my machine is working?

yes

Do these scores indicate anything about my level of apnea? (low, med. high?)

These are TREATED scores and have zero relation as to what your pre cpap category of severity might be.

[Miss Emerita]

As you can see from the resource Pugsy linked to, AHI is apnea-hypopnea index, AI is apnea index, and Central AI is the index for central apneas only. "Index" is the number of events in the specified category divided by hours of sleep.

What about the obstructive apnea index? You can figure it out by subtracting the Central AI from the AI.

And what about the hypopnea index? You can figure it out by subtracting the AI from the AHI.

[zonker]

As you can see from the resource Pugsy linked to, AHI is apnea-hypopnea index, AI is apnea index, and Central AI is the index for central apneas only. "Index" is the number of events in the specified category divided by hours of sleep.

What about the obstructive apnea index? You can figure it out by subtracting the Central AI from the AI.

And what about the hypopnea index? You can figure it out by subtracting the AI from the AHI.

m'am?

i was told there'd be no math on the test.

[ChicagoGranny]

AHI 1.1
Total AI 0.8
Central AI 0.3

They are so good that you should be banned from knowing the definitions.

[dataq1]

Set to display six months, my Resmed Airsense 10 shows on its sleep report the following:

AHI 1.1
Total AI 0.8
Central AI 0.3

A single day report may show
AHI 0.3,
Total AI 0.3,
Central AI 0.3

What may be confusing (from the math standpoint) is the difference (in the six month report) between "AHI" and "Total AI" (1.1 and 0.8 ). One might expect that to imply a 0.3 Hypopnea index over that period and a 0.5 Obstructive Index.

One the day report, one might expect that to imply Zero Hypopneas/hour and Zero obstructions/hour; the only events that night were centrals- that the cpap cannot treat.

Correct?

[palerider]

Set to display six months, my Resmed Airsense 10 shows on its sleep report the following:

AHI 1.1
Total AI 0.8
Central AI 0.3

A single day report may show
AHI 0.3,
Total AI 0.3,
Central AI 0.3

One might expect that to imply a 0.3 Hypopnea index over that period and a 0.5 Obstructive Index.

"one" (ie, you) would be wrong.

[Miss Emerita]

As you can see from the resource Pugsy linked to, AHI is apnea-hypopnea index, AI is apnea index, and Central AI is the index for central apneas only. "Index" is the number of events in the specified category divided by hours of sleep.

What about the obstructive apnea index? You can figure it out by subtracting the Central AI from the AI.

And what about the hypopnea index? You can figure it out by subtracting the AI from the AHI.

m'am?

i was told there'd be no math on the test.

Mike: Zonker, what are you doing here?

Mike: You forgot to go to your math retake exam. Now you're going to fail for sure.

Zonker: ...

Zonker: Bummer.

[zonker]

m'am?

i was told there'd be no math on the test.

Mike: Zonker, what are you doing here?

Mike: You forgot to go to your math retake exam. Now you're going to fail for sure.

Zonker: ...

Zonker: Bummer.

oh my god!! you win the internet for not just today, but for the entire week!

[ejbpesca]

Uh, well. Math is not working, nor do I understand yet.

I think I realize I do not have from MyAir an indication at all of how many apnea episodes I had the night before, or on average over a week, month etc. by indexes.

How am I to interpret these indexes? What are they supposed to be telling me?

Is there a way to convert Total AI to the number of apneas I had during a period of sleep?

Thanks.

[dataq1]

"one" (ie, you) would be wrong.

I was sincerely hoping that you PR had elected to not see anything I posted….. sigh

Anyway, just pronouncing your opinion that I am incorrect without offering an explanation (specifically how am I incorrect) doesn’t help anyone.
Please explain.

[Julie]

Uh... to get back to the OP - Myair leaves a LOT to be desired and you'd be way better off by getting Oscar (see Stickies top of front pg) which is so comprehensive, so concise and people here can help you interpret, and if necessary (tho' it doesn't seem likely now) help with tweaking whatever might need it. You could always post a couple of nights here for all to see and talk about.

[Respirator99]

Set to display six months, my Resmed Airsense 10 shows on its sleep report the following:

AHI 1.1
Total AI 0.8
Central AI 0.3

A single day report may show
AHI 0.3,
Total AI 0.3,
Central AI 0.3

What may be confusing (from the math standpoint) is the difference (in the six month report) between "AHI" and "Total AI" (1.1 and 0.8 ). One might expect that to imply a 0.3 Hypopnea index over that period and a 0.5 Obstructive Index.

One the day report, one might expect that to imply Zero Hypopneas/hour and Zero obstructions/hour; the only events that night were centrals- that the cpap cannot treat.

Correct?

CORRECT

[Respirator99]

Uh, well. Math is not working, nor do I understand yet.

I think I realize I do not have from MyAir an indication at all of how many apnea episodes I had the night before, or on average over a week, month etc. by indexes.

How am I to interpret these indexes? What are they supposed to be telling me?

Is there a way to convert Total AI to the number of apneas I had during a period of sleep?

Thanks.

The indexes are an indication of how many events you had per hour. We don't usually worry about the raw number of events as that will change depending on how long you sleep. It's the index which tells us how good or bad your apnea is. As a very rough rule, an AHI under 5.0 is regarded as "treated". Personally I need to get down below 2 to have a decent rest.

The index is simply calculated by dividing the number of events by hours slept. So if you slept for 8 hours (according to the machine) and recorded 20 events then your AHI would be 20 / 8 = 2.5.

If you really want to know the number of events, multiply the index by the hours you slept. eg if your total AI was 2.5 and you slept for 8 hours, then you had 2.5 x 8.0 = 20 events. In your case the number will be quite low as your apnea is well controlled (based on the numbers you've given us).

<edit to add>
Looking at your six month numbers, you had:

AHI 1.1
Total AI 0.8
Central AI 0.3

So your AHI (apnea-hypopnea index) is the sum of all apneas and hypopneas divided by total number of hours = 1.1
Your total AI is the sum of all apneas (obstructive, central and unclassified) divided by the hours = 0.8.
The central AI is the number of central apneas divided by the hours = 0.3.

From this it's easy to see that the obstructive obstructive apnea index is Total AI - Central AI = 0.8 - 0.3 = 0.5
The hypopnea index is the AHI - Total AI = 1.1 - 0.8 = 0.3.

For what it's worth, these are all very good numbers indicating your apnea is well under control.

[ejbpesca]

Thank you Respirator99 for the detailed explanation.

Now on to why MyAir reports fail to keep accurate usage times.