Sleep Study Report - help needed to understand

I am getting the hang of using my machine now, but still do not understand many terminologies.

If I can just start at the beginning with a few items from my Sleep Study Report. My ex Medical Sleep Specialist refused to elaborate on any items in it, and threatened to tear it up ig I asked him any questions!

So I shut up because I wanted the report. The report is from the Monash Sleep Centre in Melbourne, Australia, so I suppose some things might be different from the US model.

I would like a better understanding of these items -

1. Respiratory Events: REM RDI = 43.2/hr.
Supine NREM RDI = 49.7/hr
NREM RDI = 39.9/hr
Total RDI = 40.3/hr
Average oxygen desturation of 3% down to a nadir SpO2 of 83%.
1.2% of total sleep time with SpO2 <90%

2. Periodic Leg Movements: NREM PLMI = 32.1/hr.
Total PLMI = 28.4/hr

3. Cortical Arousals: Spontaneous Arousal Index = 8.1/hr
Respiratory Arousal Index = 16.9/hr
PLM Arousal Index = 4.2/hr
Total Arousal Index = 29.1/hr

Conclusion (part I do not understand): Frequent PLM's will require clinical correlation.

So I am hoping to understand what the above results mean, and if I need to pursue any of them further (with a different sleep specialist), or I need to monitor something in my software report (Sandman 1.4) or anything else.

Tomorrow I see my local doctor, and was wondering if I needed an oximeter.

For the last 7 days my AHi index has averaged at 2.7, with an auto setting of 7 to 12.

If you can help me out on just one or two of items, that would be great.

cheers

Mars

Sorry - I got logged out because my internet connection got broken.

The info that is on my Mars id is

Sandman Auto with Quattro FF Mask

Sleep Study Terminology
http://www.sandmansleep.com/resources/glossary.cfm

The above glossary is a very helpful aid.

Periodic Limb Movement Disorder – also known as periodic leg movements and nocturnal myoclonus. Characterized by periodic episodes of repetitive and highly stereotyped limb movements occuring during sleep. The movements are often associated with a partial arousal or awakening; however, the patient is usually unaware of the limb movements or frequent sleep disruption. Between the episodes, the legs are still. There can be marked night-to-night variability in the number of movements or in the existence of movements.

I assume this:" Frequent PLM's will require clinical correlation" means they are waiting to find out the quality of you sleep when you're breathing smoothly. If you PLM's are a result of breating distruptions, they will disappear when you're sleep improves. I don't know this for a fact - I'm guessing.

O.

Thanks Ozij

I guess only another sleep study will answer the question of whether or not I now have less leg movements.

So I might try to get another sleep study in about a years time. The conditions where I went were terrible, and it is a wonder anyone gets any sleep at all. I only got 4 hours.

cheers

Mars

mars-NLI wrote:If I can just start at the beginning with a few items from my Sleep Study Report. My ex Medical Sleep Specialist refused to elaborate on any items in it, and threatened to tear it up ig I asked him any questions!

That kind of reaction by a "god-like doctor" to a person asking some questions about their medical report should have earned him an "Ex" award. Glad to hear you fired him, whether he knows it yet or not.

mars-NLI wrote:I would like a better understanding of these items -

Well, I'll take a shot at it. I'm not a doctor or anything in the health care fields, so I may get some of it wrong, or state some things wrong.

1. Respiratory Events: REM RDI = 43.2/hr.
REM is "rapid eye movement" -- when we do most dreaming.
RDI is "respiratory disturbance index" -- an average per hour of how many times difficulty breathing disturbed your sleep by causing arousals so you could breathe, or breathe better, again. Respiratory disturbances could be a flow limitation causing an arousal, an hypopnea (partial closure of the airway with an accompanying drop in O2 and an arousal) or could be the complete, or almost complete, airway closure of an apnea.

During REM is when apneas and hypopneas are likely to hit most people the hardest. During REM that was happening to you, on average, 43.2 times an hour.

Supine NREM RDI = 49.7/hr
Supine -- sleeping on your back.
NREM -- nonREM sleep -- You were not in REM (dreaming sleep.) You were in one of the three other stages of sleep, which are:

N1 (stage 1, such a light type of sleep that it is considered just a transition into "real" sleep.)
N2 (stage 2, which is restful "real" sleep and is what most adults spend most of their sleep time in.)
N3 (stage 3, which is deep sleep, happens mostly during the first part of the night for adults, and lessens as we age.)
The stage called N3 used to be divided into stage 3 and stage 4 (both considered to be deep sleep) but nowadays the American Academy of Sleep Medicine's sleep study scoring criteria has dropped dividing that and now lumps both together in just one stage... N3 (for "nonREM stage 3 sleep")

While not in REM, but while sleeping on your back, respiratory events were disturbing your sleep to the tune of an average of 49.7 times an hour.

The two situations when apneas and hypopneas are likely to hit most people the hardest are during REM sleep and when sleeping on one's back (supine.) Worst case scenario is sleeping on your back AND being in REM, both at the same time. If the sleep study can gather information when a person is sleeping on his/her back, and/or is in REM (dreaming) sleep, that is very helpful in judging the severity of a person's sleep disordered breathing.

NREM RDI = 39.9/hr
I suppose that number includes ANY sleep position (including on one's back) and not being in REM.
The sleep positions are:
left side
right side
abdomen (sleeping on one's tummy)
supine (sleeping on one's back)

Total RDI = 40.3/hr
Overall, for the entire sleep study, you were having difficulty breathing in your sleep an average of 40.3 times an hour.
If you regard "RDI" to be somewhat similar to "AHI" (apnea/hypopnea index), an AHI of 40.3 would easily land a person in the "Severe" category of sleep apnea.

But... with your O2 level dropping under 90% only 1.2% of your total sleep time, it sounds like you were not having many apneas. Sounds like most of your RDI was made up of flow limitations not bad enough to score as an hypopnea or apnea, but I don't know that. Most sleep studies give a breakdown of the average number of apneas and average number of hypopneas. I don't see an index for those on the report numbers you've listed. That would be something I'd ask the new sleep specialist about -- what was the apnea/hypopnea index in the diagnostic study?

Average oxygen desturation of 3% down to a nadir SpO2 of 83%.
The little finger clip you wore during the study was measuring your "Saturated pulse oxygen" level all during the study.
Nadir = the lowest point -- the lowest your O2 dropped was down to 83%.

1.2% of total sleep time with SpO2 <90% Only 1.2% of the time, your O2 was below 90%. You want it to be 90% or more while sleeping.

2. Periodic Leg Movements: NREM PLMI = 32.1/hr.
In other stages of sleep than "REM", you had leg movements an average of 32.1 times an hour.
Total PLMI = 28.4/hr
The average per hour for your total number of periodic leg movements for all stages of sleep, including during REM, was 28.4
Periodic limb movements (if it's true Periodic Limb Movement Disorder) happen mostly during stage 2 sleep, I think (not sure about that), and usually don't happen during REM. If I'm not mistaken about that, that could be why the nonREM Periodic Limb Movements index is higher than when you also count time spent in REM -- which averages out to a lower "Total PLMI."


3. Cortical Arousals: Spontaneous Arousal Index = 8.1/hr
Cortical Arousals -- brain signals arousing you up out of whatever stage of sleep you happened to be in, into a lighter stage or into "wake", even if the wakeup was too brief for you to have been aware of it at all. Cortical arousals disturb sleep. A great many of them can wreck sleep architecture (spending sufficient amounts of time in each stage and in REM.)

Spontaneous arousals were arousals that did not have a respiratory problem or Periodic Limb Movement associated with them. The cause of the arousal is unknown. A dog barking, a door slamming, toilet flushing, train whistle, ambulance siren, person talking, sudden volume increase in a loud TV commercial, light turned on, a jolt of pain from an arthritic hip or bad back, med side effects... you get the idea. The list is endless for things that could cause a spontaneous arousal.

Respiratory Arousal Index = 16.9/hr
Respiratory events (flow limitations, hypopneas/apneas if any) were causing arousals on average 16.9 times an hour.

PLM Arousal Index = 4.2/hr
Arousals caused by Periodic Limb Movements averaged 4.2 an hour.

Total Arousal Index = 29.1/hr
The total arousal index including arousals from Respiratory events and arousals from Periodic Limb Movements.

Conclusion (part I do not understand): Frequent PLM's will require clinical correlation.
My guess is the same as ozij's.
I think the doctor is questioning (rightly) whether the limb movements that were noted as "Periodic Limb Movements" are just limb movements associated with the arousals to breathe, or are they true Periodic Limb Movement Disorder.

Limb movements can be reactions, so to speak, from the arousals to breathe better. If those brief wakeups to breathe better were causing your legs to give a slight jerk, they wouldn't actually be "Periodic Limb Movement Disorder."

PLMD is a sleep disorder of its own, separate from OSA (Obstructive Sleep Apnea.) If a person has a sleep study titration night where they use CPAP, the limb movements might subside when CPAP makes the breathing better and reduces the number of arousals. In that case the previously noted "PLM's" were just respiratory disturbance related limb movements...not true Periodic Limb Movement Disorder.

Periodic Limb Movement Disorder is treated with medications like the same ones used for Restless Legs Syndrome -- Requip, Mirapex, those kinds of meds. However, a PLM arousal index averaging 4.2 per hour is so low that I personally would not turn to meds for no more than that, even if it is true Periodic Limb Movement Disorder.

That would be what I'd question the new sleep specialist about most closely... were the Limb movements noted in the sleep study true periodic limb movements? Or were they just "limb movements" related to the respiratory arousals?

mars-NLI wrote:So I am hoping to understand what the above results mean, and if I need to pursue any of them further (with a different sleep specialist), or I need to monitor something in my software report (Sandman 1.4) or anything else.

Well, I'd probably want to know what the indices for apneas and hypopneas were. If there were no (or few) scored apneas or hypopneas, I'd be thinking UARS (Upper Airway Resistance Syndrome) which is treated with CPAP just like outright Obstructive Sleep Apnea is.

mars-NLI wrote:Tomorrow I see my local doctor, and was wondering if I needed an oximeter.

I think it's always a good idea to do at least one night with a recording pulse oximeter at home while using CPAP (autopap, in your case, Mars) just to be sure the CPAP treatment it keeping one's O2 level up nicely during sleep.

mars-NLI wrote:For the last 7 days my AHi index has averaged at 2.7, with an auto setting of 7 to 12.

That sounds good, Mars. Have you tried setting the minimum pressure another cm higher ( at 8 ) to see if that drops your AHI even more?

Rested Gal

Thank you, that reply must have taken some time, I do appreciate that.

The quotes in my original report were from the Clinical Notes attached to my sleep study. I now understand the Respiratory Statistics Report much better now.

My Mother (who is 90, and lives in England) suffered from Restless Leg Syndrome for many years, so your comments about PLMS are enlightening. However, in relation to that - I have some fractures in my lower back bone, combined with osteoporosis. Due to my ongoing problems with my throat closing in the daytime, as well as GERDS, I cannot take medication for osteoporosis. So I am left with exercise, and I was so exhausted for the last 2-3 years that I stopped exercising. Big mistake. So I am guessing that if I disturb my back somehow, I will get an arousal.

Is there anything on the market that I can get which will measure my leg movements?

My summary of respiratory events during the sleep study was as follows -

SpO2 awake average 95%
Average SpO2 desaturation 3%
% sleep with SpO2 < 90% 1.2%
Mean Apnea/Hypopnea duration 23.2 seconds
Longest Hypopnea 70.0 seconds
Longest Apnea 49.4 seconds
Total RDI 40.3

If I was to emulate another sleep study I assume I could use my Sandman Auto for the respiratory part of that, but I am not sure what the settings would be.

Arousal Statistics

per hour REM NREM Total
spontaneous 0.0 9.1 8.1
respiratory 14.4 17.2 16.9
PLM 0.0 4.8 4.2
other 0.0 0.0 0.0

total 29.1

A few days ago I upped my Maximum P on Apnea to 11.
Tonight I will up the lower range to 8. When I rented the Sandman Info I had it at a constant 11, so 8 should be no problem. I am getting an average leaking of 34 l/min, and no not feel any leaks, although I have a beard. Does this sound reasonable?

Typing on the computer just about does my back in, so I think I have done my dash.

Final comment

I am beginning to think that learning to be a rocket scientist has to be easier than learning all the ins and outs of sleep apnea treatment.

cheers

Mars

I keep on losing my internet connection, so once again I am Mars-NLI (not logged in) . I will check if save will allow me to log in, then submit.