What do these lab results mean?

[Janos]

A friend of mine just got these sleep test results and is wondering about her diagnosis. Does anyone know how to interpret these numbers?

AHI: 15.2 (almost exclusively hypopnea; apnea was only 0.2)
Spontaneous arousal index: 21.4

Stage 1: 20.3%
Stage 2: 55.0%
Stage 3: 15.9%
Stage 4: 0.0%
REM: 8.8%

Latency to stage 1: 46.9 min.
Sleep efficiency: 64.3%

The doctor told her she has "mild apnea" and did not recommend any treatment. But doesn't an AHI of 15.2 indicate moderate apnea? And doesn't the high number of spontaneous arousals indicate a fairly severe sleep disorder other than apnea? Is the fact that she gets no Stage 4 sleep at all significant? Should this be cause for alarm? Finally, are the low sleep efficiency and high latency numbers possibly attributable to a lab effect, or are they also likely indications of a problem?

Any clarification from all the knowledgeable people on this forum would be much appreciated.

Thanks in advance!

[Diablode]

Normal arousal index is 5-10 so 21 arousals for the night is low. However an AHI of 15 is most certainly worthy of treatment especially if there are daytime symptoms present. I have to hope that the doctor wasn't a sleep specialist, because saying an AHI of 15 isn't worth treating is incredibly ignorant. Stage 1 sleep should be around 5% so that is too high while REM is too low. They actually don't measure stage 4 sleep anymore (all part of stage 3 now) so it listing stage 4 at all may be a mistake. 16% deep sleep is a little low but not too abnormal depending on age. Sleep latency could just be trouble in the lab, though sleep disordered breathing can most certainly cause insomnia.

[Janos]

One more question I forgot to ask:

Total awakenings: 34
Wake after sleep onset: 111.0

What do these figures mean? They don't seem to correspond at all to the AHI and spontaneous arousal numbers, which add up to 173 (1 apnea event + 71 hypopnea events + 101 spontaneous arousals).

Thanks again!

[Janos]

Normal arousal index is 5-10 so 21 arousals for the night is low.

Sorry, I didn't explain it right. She actually had 101 spontaneous arousals; 21 is the spontaneous arousal index.

[avi123]

See if the following answer some of your questions:

http://www.apneasupport.org/a-bit-confu ... 29328.html

[robysue]

One more question I forgot to ask:

Total awakenings: 34
Wake after sleep onset: 111.0

Your friend went all the way to WAKE (according to the EEG) after she first fell asleep.

And the total time she was AWAKE (according to the EEG) after she first fell asleep was 111 minutes---as in one hour and 51 minutes of being AWAKE after she first fell asleep.

Please keep in mind that an awakening is not the same as an arousal. An arousal only requires a change from a deeper stage of sleep to as lighter stage---often Stage 2 sleep.

[avi123]

CPAPs don't treat Hypopneas.

[Diablode]

CPAPs don't treat Hypopneas.

Of course they do.

[jnk]

Doc may want to try a few other things before trying PAP therapy. It may be a judgment call based on the severity of symptoms and possible indications of sleep difficulties beyond the scope of jumping directly to attempting to fix breathing. There may be specific information in the detailed portion of the results that point to other sleep issues to be addressed first. AHI is a number used to qualify a person for PAP, but if it appears that a titration might not improve the numbers enough to satisfy insurance, jumping right to titration before fixing other things is not always the smartest call. In my opinion. And I'm only guessing. Not really enough info provided here to do much else, I think.

PAP, for someone who needs PAP, will likely improve all aspects of sleep-breathing, including hypopneas. APAP machines tend to react to indications of obstruction moreso than directly to the events themselves, though, depending on the home-machine event definition and algorithm, since it is the indications of obstruction that often indicate a need for more pressure, and that reaction hopefully heads off events before they happen. As I understand it. In the context of night-to-night and moment-to-moment pressures, it may be better to prevent a hypopnea than to react to one.

[zoocrewphoto]

I have two questions about the sleep study. Was it a split study or all night without any cpap equipment?

I did a split night study, and I never made it to stage 3, 4 or REM during the diagnosis phase. Butby then, I had already proven severe apnea with an ahi of 79, so they started on the titration phase. I did make it to all stages then. I do know that home I was reaching REM, because I was remembering dreams, or knowing that I dreamt most nights.

If she wasn't asleep all that much, and it wasn't typical of a full night at home, I would not be worried about the lack of stage 4 sleep in the study.

My other question. HOw was her oxygen level? That would be a huge factor in determining how severe it is.

I do wonder why the doctor did not recommend treatment as the ahi was certainly high for that. The sleep apnea is obviously disturbing her sleep. Have her take the sleep study results to another doctor who will prescribe the machine. Any doctor can, even a dentist.

[Janos]

I have two questions about the sleep study. Was it a split study or all night without any cpap equipment?
How was her oxygen level? That would be a huge factor in determining how severe it is.

It was all night with no CPAP equipment.

The oxygen numbers look like this:

Wake
Min saturation (%) 86.4%
Max saturation (%) 99.8%
Ave. saturation (%) 96.4%

REM
Min saturation (%) 92.0%
Max saturation (%) 97.8%
Ave. saturation (%) 95.8%

NREM
Min saturation (%) 91.2%
Max saturation (%) 98.2%
Ave. saturation (%) 95.6%

Total sleep time
Min saturation (%) 91.2%
Max saturation (%) 98.2%
Ave. saturation (%) 95.6%

[Pugsy]

Poor sleep efficiency. Less than optimal sleep architecture. Points to poor quality sleep for some reason. Maybe the hyponeas and maybe not. No real significant desats. Something is messing with her sleep though.
I would assume she had the sleep study because she is having some unwanted symptoms.
If it were me I would take a hard look at any of the other things that can and will mess with our sleep.
I would read up on UARS Upper Airway Resistance Syndrome.
I would probably at least want to try cpap therapy if I couldn't zero in on any of those other outside factors that disturb sleep quality and thus make us feel awful and fix them. AHI of 15 is still diagnostic and even though relatively low and no significant desats...it could still account for unwanted symptoms. Of course so could a whole long list of other things but all we can do is start trying to eliminate them one at a time to see if we can maybe get lucky and see some improvement.

[archangle]

CPAPs don't treat Hypopneas.

Care to explain this startling statement?

Treating apneas AND hypopneas is sort of the whole point of CPAP.