What are the differences between mild, moderate, severe OSA?

What makes you a candidate for the chosen category that they place you in? It seems with my AHI I think it was of 4.9 I should be in the mild category... What are the specifics for being classified as moderate?

Thanks again!

Just a comment, as I don't have the specific # in front of me. I was considered mild to moderate OSA.

However after seeing my full report from that first study, I had an overall AHI of 12.1 but in REM my AHI was 33.5 which makes me severe during REM.

As far as I know, it's not just your AHI that determines severity. There's also your desats, PLMs, RDI, sleep efficiency and the time spent in each stage of sleep.

Do you have your sleep study? My AHI was 23.0 - which is in the moderate portion of the scale - but I was diagnosed as having severe sleep apnea due to the other factors.

Total recording time 193.0 minutes. Total sleep sleep time 133.0 minutes. Sleep onset latency is 13.5 minutes. No REM latency during this recording. Sleep efficiency is 68.9%. The patient had 19.2% stage I sleep, 65.8% stage II sleep, 15.0% stage III/IV sleep and 0.0% REM sleep. Low oxygen saturation is 82.0%. The patient had 51 respiratory arousals with a respiratory arousal index of 23.0, 8 spontaneous arousals with a spontaneous arousal index of 3.6, 5 obstructive apneas, 46 obstructive hypopneas, 48 respiratory effort related arousals. The overall calculated apnea plus hypopnea index (AIHM) 23.0. Overall calculated respiratory disturbance index (RDI) 44.7. Periodic limb movements were 12 with an index of 5.4.

from http://en.wikipedia.org/wiki/Sleep_apnea

Laboratory findings
AHI Rating
<5 Normal
5-15 Mild
15-30 Moderate
>30 Severe

fortomorrow wrote:
Do you have your sleep study? My AHI was 23.0 - which is in the moderate portion of the scale - but I was diagnosed as having severe sleep apnea due to the other factors.

Yes I do and mine is...

Impression:
1. Primarily REM dependent obstructive apnea of moderate severity which are associated with arousal (overall RDI 4.9 & REM RDI 15.0)
2. Nocturnal desaturation: (minimum SaO2 86%: range 94-86%)
3. Reduced slow wave sleep & REM with severe sleep fragmentation & alpha intrusion which can be seen with chronic mood or pain disorders
4. Moderately severe periodic sleep movements
5. Moderate snoring in all position (supine > non supine)

Recommendation:
1. CPAP titration
2. T4, TSH level is not done
3. Pain inventory & psychometrics update
4. Regular exercise and weight loss if applicable
5. Improve sleep hygiene


No idea what any of it means though...

DEFINITIONS:
APNEA = cessation of airflow for 10 seconds or greater.
HYPOPNEA =>50% decrease in airflow for 10 seconds or greater with a decrease in oxygen saturation of >3%.
APNEA/HYPOPNEA INDEX (AHI) = apnea plus (+) HYPOPNEA/hour of sleep.
RESPIRATORY AROUSAL INDEX (RAI) = AHI +snoring related EEG arousals/hour of sleep.
AHI/RAI** Scale =<5 events /hour = (none); 5-15 events/hour = (mild); 15-30 events/hour = (moderate); >30 events/hour = (severe).
Respiratory related sleep fragmentation: Sleep arousals due to respiratory events or snoring.
Desaturation = Drop in O2 oximetry distribution saturation by 3% below average saturation.
SaO2 scale: >89%=(none); 85-89%=(mild);80-84%=(moderate); <80% (severe).
EPWORTH SLEEPINESS SCALE =<10=(does not indicate EDS (Excessive Daytime Somnolence));10-15=(indicates daytime somnolence-not excessive);>16 (indicates EDS).
RESPIRATORY EFFORT RELATED AROUSALS (RERAs)=Sleep Arousals due to respiratory events characterized by pressure flow limitations in the airflow indicator channel without significant O2 desaturations.
StageIII and StageIV are combined and referred to as Deep Sleep.
Sleep Efficiency = Normal is >80%
As established by AASM/ABSM 1999.

Normal Sleep Architecture:
Stage1: 5%
Stage2: 50%
Stage3: 10%
Stage4: 10%
Stage REM: 25%

Stage3&4, REM decrease as we age.

2. Nocturnal desaturation: (minimum SaO2 86%: range 94-86%)

Let me put this into perspective; if you showed up at the ER and they checked you with a pulse oximeter and your level was 86%, they would probably put you on oxygen. Have an apnea, no airflow, have a long enough apnea and your body doesn't get any oxygen, so the levels drop in your blood, same blood that goes to your brain, your heart and other vital organs. Deprive them of oxygen they need to survive and cells that make up their structure begin to die in as little as 10 seconds deprived of oxygenated blood. This process of cell death/necrosis is called inflammation, have it for years on end unchecked cholesterol putty like plague begins coating the lining of your arterial system as a temporary repair, later platelets form at the damaged site for a more permanent repair, they form a thrombus (cluster of platelets or clot), when a chunk of that thrombus breaks of into a thrombi (clot) it can travel to your brain, to your heart and where it lands it may completely block flow. What ever is on the end of that artery begins to die, if its your brain you have a stroke, if its your heart you may have a heart attack, which just depends on roll of the dice. When this plague hardens your arteries (aka hardening of the arteries or atherosclerosis) can no longer dilate to increase blood flow, when that happens you have hypertension.

so the whole idea behind this cpap thing is to keep your airway open at night so you get the oxygen you need to prevent hypoxia. Do that early enough in your life and you can avoid early death from stroke or heart attack.

Snoredog wrote:DEFINITIONS:
AHI/RAI** Scale =<5 events /hour = (none); 5-15 events/hour = (mild); 15-30 events/hour = (moderate); >30 events/hour = (severe).
SaO2 scale: >89%=(none); 85-89%=(mild);80-84%=(moderate); <80% (severe).

Snoredog thanks for the explanations..

So from my readings I should be in the mild category... No???

My readings:

Primarily REM dependent obstructive apnea of moderate severity which are associated with arousal (overall RDI 4.9 & REM RDI 15.0)
Nocturnal desaturation: (minimum SaO2 86%: range 94-86%)

And I wonder.. If I am indeed mild.. Do I still need cpap therapy? Did they possibly throw me to the moderate side so I would need a machine? I have alot of pain issues and plus the thyroid hormones to keep working on.. This is so confusing..

Recommendation:
1. CPAP titration
2. T4, TSH level is not done
3. Pain inventory & psychometrics update

It's not just the lack of oxygen that will kill you. Your sleep is fragmented, especially in REM sleep. Lack of REM sleep can cause behavioral disorders (depression, hallucinations, mood disorders), decreased brain mass, cell death, among other things. You need REM sleep to repair your body.

Anxiety and pain can also severely affect sleep. You need to get those taken care of, *in addition* to CPAP therapy.

I would think that the pain itself is reason enough to try using the machine regularly for a while. Chronic pain was my main symptom, though we thought it was other things and I had already undergone two surgeries and was looking at a third. Three months with my machine working well and I only have mild pain which I believe will improve with my increasing exercise.

Your AHI in REM sleep is high enough to be of concern, especially with your oxygen desaturations. Snoredog gives a good explanation of that including how it leads to constant inflamation which means constant pain.

.

MichelleFL wrote:

Snoredog wrote:DEFINITIONS:
AHI/RAI** Scale =<5 events /hour = (none); 5-15 events/hour = (mild); 15-30 events/hour = (moderate); >30 events/hour = (severe).
SaO2 scale: >89%=(none); 85-89%=(mild);80-84%=(moderate); <80% (severe).

Snoredog thanks for the explanations..

So from my readings I should be in the mild category... No???

My readings:

Primarily REM dependent obstructive apnea of moderate severity which are associated with arousal (overall RDI 4.9 & REM RDI 15.0)
Nocturnal desaturation: (minimum SaO2 86%: range 94-86%)

And I wonder.. If I am indeed mild.. Do I still need cpap therapy? Did they possibly throw me to the moderate side so I would need a machine? I have alot of pain issues and plus the thyroid hormones to keep working on.. This is so confusing..

Recommendation:
1. CPAP titration
2. T4, TSH level is not done
3. Pain inventory & psychometrics update

I look at your findings and read the overall RDI of 4.9 as not relevant. What is relevant is where your apnea index is worst, your REM sleep. There you have borderline moderate sleep apnea. Think about it, you have two things working against you here. First your rest is being disturbed every 4 minutes during REM sleep. Second, you are stopping breathing long enough to get your oxygen levels down to 86% of normal.

Snoredog, I wish our Dr had laid it on the line for my husband 10 years ago like you just did, when he "sort of" recommended he go for a sleep study which we totally ignored since we weren't told the consequences. Now a Triple Bypass and Aortic Valve Replacement later, along with a no quality of life to speak of, we finally decided to do our own research and took the steps necessary to turn things around. Now after 2 months we're beginning to get our life back again. We've been to Atlantic City twice(we only live an hour away) and we watch TV together at night and I have to now remind him it's time to go to sleep. We're both seniors so we have to make every day count. You and the great folks on this forum have made this journey so much easier for us, don't know where we'd be without you. Blessings to all.

don't forget, what snoredog describes is only a part of it. That is what happens due to the lowered oxygen levels in our blood both immediately and over time. There is also the effects of not having normal sleep architecture. Sleep architecture in a normal person goes through a series of stages over a 90 minute period. For us with OSA, we cycle through our own disrupted sleep cycle over a period of minutes. We rarely enter REM sleep or the deeper stages of sleep and this causes us to have serious sleep deprivation symptoms even though we may be in bed and not fully conscious for ten hours or more. Sleep deprivation has been used as a form of torture. Menachim Begin described his experience of being tortured with sleep deprivation as being all consuming and sleep became more important than anything including food, water, and air. People with sleep deprivation have impaired ability to do anything comparable to having a blood alcohol level of .1. To learn more about these symptoms, just put in sleep deprivation into google or here or any search engine.

I can only relate my experience, but have to give credit to my family to insist I be tested this year.
As only in my 30's, I've suffered with sleep apnea and insomnia for at least a decade, but it took a
doze behind the wheel at 4pm on a peaceful saturday to get my full attention.
Both my parents and younger siblings are on CPAP therapy.......my father for over 15 yrs now, yet
I resisted, and thankful for all their urging.
Had three studies this year, and never once entered 'REM' sleep, but would love to know if i've finally
achieved that now. My diagnosis in sleep lab was quite severe, and I assume its a genetic makeup in
our family, but pleased to report I am feeling more human with CPAP therapy.
I truly never embraced sleep, it was an annoying factor in my life that resulted in hours of staring in
the dark, hours and hours upon end.
Can finally say I look forward to heading in for the night, yet wont say the insomia is cured, but the quality of
sleep I'm receiving is FAR better than I ever recall.

Without a cpap, these are the determining factors:

Mild = Tired and cranky
Moderate = Ticked off and ready to kill.
Severe = Too tired to kill.