My Sleep Studies: Your Thoughts, Please

I've been on cpap for 3 weeks now. I think I'm one of those who doesn't feel "better" immediately. One of the reasons my sleep doc brought me back for a second study (my titration) was because I've been previously diagnosed with coronary artery disease. I'm 36 now, and when I was 30 I had two stents placed in my LAD artery, which was 95% blocked. My doc was concerned about my desaturation numbers.

I'll be honest... my initial struggle was (and maybe still is) to accept the results of my study. My AHI is so low that I question whether or now I should be on cpap. My primary doc. has told me that the doc who did my study and prescribed my treatment is very discriminant in his diagnosis' - in other words, if he diagnosed me, I have it. Maybe I'm just looking for some confirmation from this forum. You guys seem pretty bright on here. Anyway, here's my numbers...


Initial Sleep Study (No Titration)

Sleep Architecture: total record time = 6 hr 55 min / total sleep time = 3 hr 56 min / sleep efficiency 56.9% / sleep onset occurs through non-REM at a latency of 26 ½ min / REM latency noted at 4 hr 44 min

Electroencephalogram: wakeful period = 43% / stage 1 = 9.6% / stage 2 = 44.5% / stage 3 &4 0.0% / stage REM = 2.9%

Electromyogram: PLM index = 4.3

Electrocardiogram: avg. waking heart rate = 67 / avg. sleeping heart rate = 67

Respiratory: apneas present = 9 (8 obstructive & 1 central) / hypopneas present = 15 / AI = 2.28 / AHI = 6

Snoring: snore index = 14% (all 556 episodes of snoring occurred in lateral position) / oxygen desaturation = 88% at nadir (longest desat. below 88% lasted 6 seconds)

“Review of hypnogram reveals unconsolidated sleep and frequent awakenings at night.”
“He would be a good candidate for CPAP titration in view of his cardiac pathology.”

Second Sleep Study (CPAP Titration)

Sleep Architecture: total recording time = 7 hr 6 min / total sleep time = 4 hr 31 min / sleep efficiency = 63.6% / sleep onset occurs through non-REM at a latency of 19 min and REM latency is prolonged at 5 hr 57 min

Electroencephalogram: wakeful period = 36.4% / stage 1 = 7.5% / stage 2 = 52.9% / stage 3 &4 0.0% / stage REM = 3.2%

Electromyogram: PLM index = 0

Electrocardiogram: avg. waking heart rate = 67 / min. sleeping heart rate = 65

CPAP Titration: gradually to a pressure of 9 cm / saturation = 91% / AHI = 0

My Current Numbers
I'm waiting on my encore software, but my LCD has been showing an API of around 2 each night and a leak rate of around 5 l/min (taking my mask into consideration). .

Thanks all,
Mike

Mike,

Just guessing here, but with your cardiac history, even with marginal numbers, it's a cardiac stress best avoided. I think it was Snoredog who posted a lengthy explanation a few weeks ago about the effects of sleep apnea, and it included a part about inflammation and arteries. Especially for you, any decrease in that risk seems to me to be desirable.

I notice you were lacking in deep and REM sleep. Though it does not apply to everyone, often apnea is worse when sleeping deeply and in REM. If you happen to sleep better at home, your study may not be reflective of what your numbers could really look like.

I do hope your cpap treatment is quickly therapeutic and you get better sleep and feel the results.

Kathy

Thank-you, Kathy. I appreciate your thoughts.

Anyone else?

I agree absolutely with what Kathy said. Anyone who has already had cardiac problems and sleep apnea, no matter how "mild" the apnea diagnosis, really, really, really needs to use "cpap."

I wonder if any of your meds are interfering with getting REM sleep. Both the study nights showed an extremely long latency (how long before it happened) before your first REM period showed up.

During the diagnostic night, you had been asleep almost 5 hours before REM happened. REM latency 4 hours, 44 minutes.

On the cpap titration night, you had been asleep almost 6 hours before REM happened. REM latency 5 hours, 57 minutes.

REM (dreaming sleep) happens in cycles throughout the night, the first REM generally occuring about 90 minutes after going to sleep. There are usually 4 or 5 REM periods during the night, with each REM period usually lasting longer than the last one. "Normal" sleep architecture consists of about 25% of the time spent in REM.

With it taking sooooo long for you to reach REM on both your study nights...and especially on your cpap titration night....and having so little REM at all, I'd really suspect you're not getting anywhere near enough REM at home either. I'd talk to the doctor about the possibility of one or more meds being REM suppressants. If that's the case, I don't know what they can do about it. But, I really think a sufficient amount of REM is probably one of the more important components of refreshing sleep.

Just have to disagree with RG on the REM latency here. Maybe i'm reading it wrong, but for example on the first night you only had 3+ hours of sleep, so there is no way you could have REM latency of 4+ hours. I think the REM latency was calculated from the start of the recording time.
But what's weird is if you look at the sleep onset latency (on the order of 26 and 19 minutes for the 2 studies, if I interpret it correctly), then you indeed didn't reach REM for a long time. Looks like you woke up quite a bit during the sleep study. I would be asking for more detailed reports, if I were you. In any case the frequent arousals probably contributed to the late REM latency. I would definintely ask more info on the total number of arousals you had, whether respiratory related or not... that is no where on that report but is probably a large factor despite your low "official AHI".

As both Kathy and RG noted, your REM and SWS (stages 3&4) time are horribly low, so your sleep is definitely fragmented. Also your snores were quite high - and those can also cause airflow reduction. But the definitive factor was your oxygen desaturation - that happens when you have airflow reduction (regardless of a low magical AHI). And the result is that CPAP will open up your airway and prevent the desaturations.

Oh one other point - during the titration they could only reach a desaturation of 91%, which still seems a bit low. What is your normal oxygen saturation when you're awake? Do you have other breathing/lung issues?

I wonder if we're looking at a real-live case of UARS here?

Mike - one reason you're not feeling better immediately might be because your oxygen levels are still low even with CPAP (incorrect pressure? incorrect machine?). A second possibility is that you're still not hitting REM, either because you're still having a lot of arousals (for what reason I don't know) or you're so backlogged on good sleep that it's taking some time for your body to adjust.

In addition to the items mentioned above that you should ask your sleep doc, I would also push for an overnight pulse-ox.. that will at least determine whether your oxygen desaturation is significant.

Snoredog suggests to take melatonin, because it can increase REM sleep. That may be an option too.

If I were you I wouldn't give up on the CPAP yet.

I would say that both of my nights at the sleep lab were similar to what I was experiencing at home. I just started cpap about 3 weeks ago, and I think I've dreamed more in these weeks than the past 10 years! But, I still have a hard time falling asleep, and whenever I wake up (2-3 times a night) I tend to stay up for 30 minutes or so, then go through the whole process all over again.

I'm actually not on any medication right now - other than some stuff for my sinus', but that's only been in the past week or so. I'm one of those people whose mind goes a million miles an hour once they lay down. I can be falling asleep while watching tv, but as soon as I go to bed my mind "wakes up."

On the oxygen level... I was at my doc's last week (sinus) and as part of the routine they put the oxy-thing on my finger. I saw it read at 98% - yet, my study shows me with a 91% while being titrated. Is it normal for this number to rise and fall like that depending on activity (awake or asleep)? I don't believe I have any other breathing/lung issues. I'm 36, slightly overweight, and quite smoking 5 years ago.

On UARS... I had to google it. First hit was "Upper Atmosphere Research Satellite." I said "huh?" Then I saw the next hit - "Upper Airway Resistance Syndrome." That made more sense. Interesting - I guess I'll have to read up on it a little more.

Thanks for your insight.

eutychus wrote:I'm actually not on any medication right now - other than some stuff for my sinus', but that's only been in the past week or so.

If your sinus meds contain any sort of ephedra-like substance, that can keep you awake, especially if you take it later in the day.

eutychus wrote:I'm one of those people whose mind goes a million miles an hour once they lay down. I can be falling asleep while watching tv, but as soon as I go to bed my mind "wakes up."

I know what you mean! Now that my therapy is going better, that happens to me less and less. I think it's our subconscious mind afraid to go to sleep because we know we're going to be suffocated once we close our eyes!

eutychus wrote:On the oxygen level... I was at my doc's last week (sinus) and as part of the routine they put the oxy-thing on my finger. I saw it read at 98% - yet, my study shows me with a 91% while being titrated. Is it normal for this number to rise and fall like that depending on activity (awake or asleep)? I don't believe I have any other breathing/lung issues. I'm 36, slightly overweight, and quite smoking 5 years ago.

I'm no doctor so there's no way I could tell you what your normal oxygen saturation should be. But from what I've read, your number should be pretty stable, including when you're sleeping. It seems reasonable to me that your night-time numbers should be similar to your day-time numbers. I would check with your doc on this one, and ask why your night-time numbers were so low.

eutychus wrote:On UARS... I had to google it. First hit was "Upper Atmosphere Research Satellite." I said "huh?" Then I saw the next hit - "Upper Airway Resistance Syndrome." That made more sense. Interesting - I guess I'll have to read up on it a little more.

There's a very good write-up on this from a sleep doctor who now and then frequents this board:
Flow Limitation/UARS and BiPAP (BarryKrakowMD) (also can be found under "Our Wisdom" at the top). Unfortunately he seems to be a bit alone in his thinking (or, more likely, like Snoredog's sig: "someday science will catch up to what I'm saying..." ).

With your waking saturation normal and your sleep (or attempting to sleep) saturation dipping lower than it should - the number of you AHI is almost irrelevant. Look at it this way: Your sleep study showed that the way you sleep at night is not giving your body enough oxygen, nor is it giving you enough rest - since your rarely reach either REM or deep sleep.

The fact you're dreaming more in these 3 weeks than in the past 10 years indicates that the therapy is actually working, and you are no longer being startled out of REM by your collapsing airway. I think I'd call the doc, report I'm dreaming much more, and ask him if I should try to raise the pressure a bit - because of the possibility that now that you're dreaming, you're having more partial obstructions than before - they had you at 0 AHI during the study, but that's not the case at home now... Have you evere considered tracking you oxygen saturation at night? If I could afford it, I'ld buy a pulse oximeter to see what my oxygen levels were undre cpap.

IIRC, one of the hallmarks of UARS is actually no desturation. People with UARS are somehow aroused by the obstruction before the destaurations become significant. So I wouldn't say UARS. I don't know why your oxygen saturation at 9 was 91% and not higher, but I wonder if slightly higher pressure my give you better saturation as well.

Your sleep architecture (amount of time is different stages) was still abmormal during the titration - but seems to be changing now that your using cpap at home. All in all, both your sleep doc. and you primary doc. are making a lot of sense.

O.