Open question #7: PLMS, Sleep fragmentation and WED

[Frunobulax]

Hi again,

one step closer to the magic number of questions - 10

I could phrase this as a very short question:
What is the connection between WED and PLMS?

But this doesn't explain what I really want to know. Let me break it down into several detailed questions.

• WED and PLMS are clearly correlated, but is there a cause and effect relation (whatever causes PLMS is likely to cause WED, or the other way around)? Or are they different symptoms of one disease, do they have a common cause?
• As far as I know there are two kinds of PLMS: The ones that do not disturb sleep (but may disturb the spouse ), and the ones that cause arousals (the sleeper will wake up) or micro-arousals (preventing deep sleep, usually unnoticed by the sleeper), causing fragmented and less restful sleep. Are WED sufferers more likely to have the PLMS causing arousals?
• Are the sleep arousals caused by the PLMS, or are the PLMS just a reaction to an arousal that was caused by something else (like WED symptoms)?
• Is it interesting to monitor PLMS at all?
• Can the presence and severety of PLMS give an indication on how the WED should be treated? Are certain forms of WED (painful/electric, ideopathic/secondary) more associated with PLMS than others?

I'm asking these questions because I notice rather significant variations in my sleep quality. I went through a long list of WED drugs during the last year, and had months where the total amount of sleep wasn't that bad (5-7 hours per night), yet I was completely in "zombie" mode - significant daytime sleepiness, memory problems, the whole package, even after nights with decently long sleep. During the last months my WED symptoms were just as bad and I had perhaps less sleep than before, but I felt fairly refreshed after a good night - and even a few bad nights wouldn't cause "zombie" mode. I can rule out sleep apnea because I have a CPAP machine, but my sleep neuro says I don't really need it because the number of apneas per hour without the CPAP is rather low - with the CPAP it's a solid zero. So I guess there must be other factors at work, and since I know that I have micro-arousal-type PLMS, it is likely that the PLMS made the difference.

The bottom line is: The efficiency of WED medication should not exclusively be measured on how good it relieves the waking symptoms, but also how efficiently it treats the PLMS. But it seems clear that we need to get a better understanding of the connection between WED and PLMS.

[sleepdancer2]

With the many variables we see in these disorders, it would be hard to establish relational absolutes. Yes, some may have both, but plenty have either/or. I happen to have both, but interestingly (to me at least ), I didn't have RLS/WED until after I started meds for the PLMD. And, after going off all PLMD meds, my RLS/WED symptoms over time dramatically decreased from insufferable to usually tolerable.

About your CPAP. If insurance covered getting a machine, you met the criteria for needing to be treated. One school of thought is mild sleep apnea does not need treated. Without knowing the specifics of your test results, I can say only that I strongly disagree with that perspective for multiple reasons. For starters..

#1 Sleep studies are notorious for not capturing the full picture of the severity of a person's sleep apnea. Only in examining the fine details of the report can one get a decent idea if the study likely captured their worst case scenario. Most don't sleep in a lab with all the distractions as well as they might at home. Also, if a study doesn't capture REM sleep while supine, it is more likely to not have captured the possible worst case scenario. Mild may only mean you were mild that night. But then again, some actually do have a mild case by industry definitions. Even mild sleep apnea can disrupt sleep and cause daytime symptoms.

#2 There are limb movements and then there are periodic limb movements. Limb movements can be prompted by things such as pain, RLS sensations, or an effort to breathe with sleep apnea events. Using CPAP will help the ones caused by respiratory events by virtue of stopping those events. With periodic limb movements, there are diagnostic levels, with Periodic Limb Movement Disorder being at the furthest end of that spectrum. When one has limb movements that cause arousals, it makes the accurate classification of sleep apnea difficult to discern. On the flip side of that, having sleep apnea makes the accurate diagnosis of the severity of limb movements difficult. The two conditions can "mask" each other. I am immediately suspicious that the full picture may not have been uncovered when there is a dual diagnosis.

#3 It is not unusual for one to experience worsening of PLMD with successful CPAP treatment. The better sleep that comes from stopping the apneas gives the limb movements an open forum to more fully manifest. It is my opinion that sleep apnea is so threatening to health and well being that it deserves the utmost of attention. Without treating my sleep apnea I would have no motivation or energy to address my legs, as I was dying a slow miserable death from the sleep apnea. Having all your events prevented by the machine is enviable and reason to count your blessings.

Sorry to go off on a tangent here. This subject is near and dear to my heart and I suffered many years under the care of medical professionals who just didn't "get it".

[Frunobulax]

Yes, actually my WED doctor (sleep neuro) and my sleep specialist disagree on this one too. I am also wary of a "mild" diagnosis if significant PLMS with arousals were diagnosed at the same time, and I also suspect that one can judge sleep apnea only if the PLMS are taken care of. Therefore I keep using my CPAP machine - maybe I'll give sleeping without it another try if I manage to lose another 20 pounds...

[ViewsAskew]

Here are your questions and my responses.

WED and PLMS are clearly correlated, but is there a cause and effect relation (whatever causes PLMS is likely to cause WED, or the other way around)? Or are they different symptoms of one disease, do they have a common cause?
They are so little studied - who knows? My gut says they ARE related in some way, but unsure of how. I had PLMS for 10 years before I had WED. I started having PLMS as a toddler. WED didn't start until my early teen years. But, when I took meds for PLMS, it made my WED augment immediately (within a week from very mild to moderate and from moderate to severe within a month or so).

As far as I know there are two kinds of PLMS: The ones that do not disturb sleep (but may disturb the spouse ), and the ones that cause arousals (the sleeper will wake up) or micro-arousals (preventing deep sleep, usually unnoticed by the sleeper), causing fragmented and less restful sleep. Are WED sufferers more likely to have the PLMS causing arousals?
In the sleep studies I've seen, yes. But, I've only seen a handful. A sleep doc would be needed for that. Maybe Dr B would know.

Are the sleep arousals caused by the PLMS, or are the PLMS just a reaction to an arousal that was caused by something else (like WED symptoms)?
I think both. Before I had WED regularly, I had severe PLMS. In my sleep study before medication, the PLMS awakened me. BUT, since I now have severe WED, too, I know the WED awakens me. It's different. I am dreaming of moving or am aware that my legs are moving from WED and it takes me several minutes to come out of sleep into wakefulness. It's clearly different, but both awaken me.

Is it interesting to monitor PLMS at all?
Interesting as in helpful? Not sure. I'd be curious just to know if it changes and to see if there was a correlation to anything, but I don't see how it would help otherwise.

Can the presence and severety of PLMS give an indication on how the WED should be treated? Are certain forms of WED (painful/electric, ideopathic/secondary) more associated with PLMS than others?
No idea. My mom's side of the family - multiple generations - has the electric type, clearly inherited. My mom has no PLMS. My sister does. My uncle does. Not sure of my other uncle or my grandmother or my brother (genetically, a half brother). My dad had no WED, but had PLMS. No idea if it bothered him and he died young so can't ask. All of us have electical, but not all of us have PLMS. And, my sister and I could have two separate sets of genes that combined to make a different form. I believe I read research that suggested just this, but am very foggy today, so may be misremembering.

[Rustsmith]

There are a number of interesting points in this discussion about the correlations between RLS, PLMs and sleep apnea. My personal experience was that I was diagnosed with a specific type of "mild" sleep apnea called Upper Airway Restriction Syndrome (UARS) along with PLMS and WED. The quickest differentiation between UARS and Obstructive Sleep Apnea (OSA) is that the number of true apneas are quite limited with UARS, but the hyponeas that are more prevalent also frequently result in micro-arousals. UARS is also more frequent in younger, small, thin females while OSA is more likely to occur in older, overweight males. This means that the effect on sleep of UARS is very hard to distinguish from PLMS unless you look at the timing and cause of the arousal. I should also add that UARS requires more sophisticated monitoring equipment than is used in most sleep studies, which may be part of the reason for the issues with sleep studies that sleepdancer mentioned.

As for PLMS, it is said that 85% of those of us with WED also have PLMS. It would be interesting to know if there is something that the remaining 15% have in common. Are they mostly secondary WED? Were they boarderline on the diagnosis of PLMS (almost enough leg movements, but not enough to qualify for a diagnosis), or do they have very mild RLS so that the PLMS just hasn't shown up yet.

As for PLMS, I found some of the information about other causes of PLMS in this paper quite interesting - http://www.jpgmonline.com/article.asp?issn=0022-3859;year=2010;volume=56;issue=2;spage=157;epage=162;aulast=Natarajan
However, the fact that the treatments for PLMS and WED are usually the same implies an organic relationship and similar causes. Could it be that the "idiopathic" PLMS is just cases where the daytime WED symptoms are too mild to be noticed? The simple fact that one occurs while awake and the other while asleep seems like a very fine distinction (even though it does have some relevance).

And finally a couple of comments on CPAP treatments. I believe that insurance coverage plays a role in many "mild" sleep apnea diagnoses at sleep clinics. The insurance companies require an AHI score of 10 to qualify for coverage. Scoring of the sleep study data is subject to some degree of interpretation, especially in mild cases. So if the initial pass at scoring a patient come up 8 or 9, there is an incentive for the clinic to review the data more closely to reach a value of 10. For UARS where the majority of the AHI is going to be the more subjective hypopneas, this is easier to do than the more clearly defined apnea findings.

As for CPAP treatments, CPAP appears to be more effective for the control of OSA than UARS. On a sleep apena bulletin board, I have seen reports of people with moderate to severe OSA with treated AHI values less than 1. So it stands to reason that mild cases should be zero. As for UARS, most of the CPAP machine software is currently optimized for the treatment of OSA. The sensitivity of the machines to the hypopneas prevalent in UARS is much less. This is probably part of the reason why many insurance companies will not cover CPAP treatment of UARS.

[Frunobulax]

And finally a couple of comments on CPAP treatments. I believe that insurance coverage plays a role in many "mild" sleep apnea diagnoses at sleep clinics. The insurance companies require an AHI score of 10 to qualify for coverage.

This is different here in Germany. The insurance companies will cover CPAP machines if a sleep doctor writes a letter pointing out why the patient needs it. My sleep doctor said I'm not a bad case, but severe enough to warrant CPAP therapy - especially since my WED restricts the amount of sleep, which makes it important that the sleep I get is as restful as possible.

[debbluebird]

I recently realized that I have very little WED. When I do have WED, then I am very restless in bed, having to move. This doesn't happen to me very often. I mostly have PLMs every night. I also have sleep apnea. But I do know that most of my life, I moved my legs, in my sleep and just before I went to sleep. Back then, it didn't keep me awake.

[sleepdancer2]

Just a note on the difference between WED movements and PLMD. WED movements will be random as far as timing and varied in appearance. In PLMD, the periodicity is the identifier. The movements are rhythmic - you could time them on a stopwatch - and they will be repetitive and stereotypical. Even though the movements in my video link are exaggerated as a result of augmentation, you can still see their patterned appearance.

[ViewsAskew]

Sleepdancer2, good point. I find that seems less so with PLMW. Not sure why. I don't have them that often (thankfully), but they seem less regular.

To me, the best way to differentiate is that there is NO sensation with PLMs and there usually is with WED/RLS. I may feel as if my body will move anyway with RLS/WED, but technically, we are moving our own limb/body part in response to the icky sensation. With PLMs, the movement is being done to us. When I have PLMWs, it's a very bizarre feeling to be standing and have your leg shoot out from under you!

[sleepdancer2]

That's interesting ViewsAskew. Is your PLMW from augmentation? There was a period of a few years where my PLMD was showing up when I was awake enough to be aware but not wide awake. If I opened my eyes or became alert, the movements would immediately stop. Just curious, does your PLMW happen with your eyes open? I remember many times becoming aware of the movements but knowing they'd stop if I opened my eyes so I'd wait till my legs were in the air and open my eyes real quick trying to get a glimpse of them in action. (lol The things we do to entertain ourselves with this stuff. ) Anyhow, during this period I became aware of sensations that preceded the explosive movements. It was like a drawing or pulling sensation in my knees that increased until bursting into movement. The best way I can describe it is like a rubber band being twisted till it was tight then suddenly released. Always interesting to hear what others experience.

[ViewsAskew]

That's interesting ViewsAskew. Is your PLMW from augmentation? There was a period of a few years where my PLMD was showing up when I was awake enough to be aware but not wide awake. If I opened my eyes or became alert, the movements would immediately stop. Just curious, does your PLMW happen with your eyes open? I remember many times becoming aware of the movements but knowing they'd stop if I opened my eyes so I'd wait till my legs were in the air and open my eyes real quick trying to get a glimpse of them in action. (lol The things we do to entertain ourselves with this stuff. ) Anyhow, during this period I became aware of sensations that preceded the explosive movements. It was like a drawing or pulling sensation in my knees that increased until bursting into movement. The best way I can describe it is like a rubber band being twisted till it was tight then suddenly released. Always interesting to hear what others experience.

Yeah, mine happens when I'm wide awake. Standing, sitting, eyes wide open . When I'm standing, my knee shoots out, leaving me to almost crumple on one side as I no longer have support from that leg. And, yes, it was worst with augmentation. It rarely happens now. It took about a year after stopping DAs for it to abate to its current level of rarely.

My WED feels more like what you describe, but not quite. It's definitely a build up of a sensation that must resolve itself. To me, it's my regular WED on steroids, which is why I've always felt it was WED, not PLMW. But, when they say that WED is voluntary, this to me does not feel voluntary! The only way I can resolve what the literature says with my experience is that I move, but much as I would if I touched something hot - the nerves are so frazzled by the sensation that you MUST move and you do it without thinking about it - so fast that maybe your limbic brain is in control, not your rational one.

[Rustsmith]

I used to have occasional instances of PLMW before I started DAs. They would almost always occur after I got in bed but was waiting for my wife to finish getting ready. They always occurred with no warning and were usually just a very violent leg kick. However, I remember one night where I really scared her just as she was getting into bed. All of a sudden both legs and both arms violently lashed out in front of me and then dropped back to where they were.

I was also diagnosed during my sleep tests has having the normal, rhythmic movements of PLMS.

As for my WED, I have the form where there isn't much sensation, only an urge to move. When I do have sensations, it is usually feels like I have a tremor in my hands, chest or legs, but I can see that nothing is moving.

[badnights]

I don't have clear PLMs. Although one sleep study showed that I do have them, they have never been an issue that I know of. I tend to think of them as a larger problem with lots of possible causes, not something tied intimately to WED but to the larger sleep-wake picture, which WED is also tied to.

The fact that the same treatment controls both WED and PLMD means little in terms of causes - just look at how the same treatment can be used for WED and Parkinson's, which have quite different physiological causes even though they share at least some real estate in the brain. Or look at the various conditions gabapentin is used to treat - WED, seizures, nerve pain. Similar, but different causes.

Frunobulax, you mentioned a variation in your sleep quality that didn't match the variation in WED intensity, and that you could end up in zombie mode despite apparently having 7 hr sleep. That happens to me a lot, and I've speculated on it here before, but my theory is different than yours - because I don't have noticeable or memorable PLMS. I think the zombie fog happens because I don't get enough deep sleep, and some nights I get less than others.

The reason for that, for not getting enough deep sleep, has to tie in somehow to the ultimate cause of WED. Not getting deep sleep must relate to the hyperarousal that is, I think, being increasingly recognized as a hallmark of WED. Too many excitatory transmitters like glutamate running around the brain, or something like that.