I asked everyone on this forum the following 3 questions:
1. do you prefer to sleep on your back, side or stomach?
2. did you or do you have cold hands or feet?
3. did or do either of your parents snore and do they have any medical problems?
Overwhelmingly, the answers were: mainly side and stomach only, the vast majority have cold hands or feet, and almost everyone has one or two parents that snore heavily with various degrees of heart disease. Many of you also complain of intense fatigue.
This sounds amazingly like what I see in patients with upper airway resistance syndrome. UARS is a mild variation or precursor to sleep apnea, but it's different in that it's typically seen in young thin women (and men) who don't snore, can't sleep on their backs, have cold hands or feet, have normal or low BP with lightheadedness or dizziness, chronic fatigue and unrefreshing sleep no matter how long one sleeps, various unexplained gastrointestinal problems, hypothyroidism, depression, and many others. Later on, as they gain weight many of these symptoms improve (especially the cold hand and dizziness), but begin to develop high blood pressure, diabetes, heart disease, heart attack or stroke.
Anatomically, they all have relatively narrowed jaws with very narrowed breathing passageways when on their backs. Due to gravity, the tongue (which takes up too much space within a smaller jaw cavity) falls, back partially, and then when in deep sleep, can obstruct completely due to muscle relaxation. If you stop breathing and wake up after 10 seconds, then that's called an apnea. If you stop breathing and wake up anywhere from 1-9 seconds, then you'll wake up to light sleep or be awake, but it won't get counted as an apnea. The minimum number of apneas you need every hour on average to receive a diagnosis of sleep apnea is 5. But if you stop breathing 25 times every hour and wake up after 2-9 seconds, then you're told you don't have any sleep apnea.
There is a significant group of people who stay in UARS, and with the chronic extra stress response due to the inefficient sleep with repeated arousals, their nervous systems and immune systems are heightened. Having a hypersensitive nervous system or immune system can have certain consequences. UARS patients have normal or heightened nervous systems, whereas OSA patients have diminished nervous systems.
Your anatomy is hereditary, so you got your smaller jaws from one or both of your parents. As people with UARS get older and gain more weight, they'll have the classic signs and symptoms of obstructive sleep apnea: severe snoring, breathing pauses, and medical complications such as heart disease, depression, heart attack or stroke.
I can't say if one definitely causes the other but I can say that there's a definitely link between MS and sleep-breathing problems. Some of you already have sleep apnea. I know it's impractical, but it would be interesting if everyone could get formal sleep studies to see how many people with MS have OSA or UARS. One is not exclusive of the other, so if you have a family history of snoring and heart disease, it's important to get checked for sleep apnea.
Snoring is a sign of major breathing problems at night, and is nothing to be laughed at. A heavy snorer should definitely be checked for sleep apnea, since untreated, it raises your heart attack and stroke rate by 3 and 5 times, respectively. Not to mention high blood pressure, obesity, depression, anxiety, heart disease, and Alzheimers (this one's controversial, but there's plenty of convincing evidence). Also, you don't have to snore to have significant sleep-breathing problems.