I have noticed that a few of the members have had some questions about these 2 disorders. With this post we will learn about them together. My disclaimer as most of you know I am just a lowly PSG studying for my RPSGT certificate. Please do not take anything that I post as a diagnosis. You should always seek the advice of your PCP before you do or accept any information you might read on the internet, or anywhere else for that matter.
This is what I know. These disorders are both classified as neurological disorders. However studies have proven, or are currently trying to prove, that they are not always neurological in origin. RLS is a disorder that causes an overwhelming urge to move the legs(sometimes arms). Some people just have to rub their feet together while others actually have to get up and walk around. This can be extremely bothersom when you are trying to relax or SLEEP. There is some argument as to whether this is actually a sleep disorder because it happens while you are awake. I believe it to be a sleep disorder because it can keep you from falling asleep. It is more of an all the time disorder, or what some might call a tick. These movements are scored as isolated leg movements from the time of lights out to sleep onset. They are interpreted on a case by case study. Meaning that if you are experiencing this urge let your PCP, sleep doc, or sleep tech know otherwise they might not catch it.
http://www.rls.org/Page.aspx?pid=471
If you have RLS there is a high probability that you have PLMD, but not always.
http://www.rls.org/Page.aspx?pid=471
PLMD is a parasomnia, Which means that it occurs during and disrupts sleep. This is a rythmic movement of the legs usually, but sometimes the arms as well. These movements generally happen every 20-40 seconds. To be counted as a PLM on a psg 4 individual movements must be recorded in 90 seconds or less to count. so 217 scored isolated leg movements would be 54 PLMs. If you are treating your apnea and not your PLMD chances are you are still not getting a good night's sleep.
PLMD and RLS patients can be sleepwalker,talkers, and eaters. They have also been know to lead to REM behavior disorder. This is the neurological side of the problem. I would be happy to cover these in another post if you like.
I have found a few studies that show that RLS and PLMD are not always neurological in origin. They can sometimes be a result of low iron, kidney probelms(passing stones, or an infection), or can be a warning of or happen during renal failure.
http://www.faqs.org/patents/app/20080250512
They can also be an ealry warning sign for MS, Parkinsons, Or a nervous system disorder of some sort including spinal chord damage.
http://www.faqs.org/patents/app/20080250512
Please keep in mind that I am just a PSG on the road to certification. If you think you might have one, or both of these disorders consult a physician. I just wanted you to have some of the facts about them. I NEEDED you to know that these are not just things that can be blown off because you doubt your sleep study. THey are serious and could be your body screaming for help. Don't ignore your body it knows you as well as you kknow it, maybe better.
This is discussion. Please feel free to post any questions or pertinent information on the subject. Techs/Docs please correct and educate me on anything I might have been wrong about.