-SWS wrote:... I'm fairly certain you already know this, John... ...
Thanks for confirming my understanding of what I had read. I had not meant to imply that one mixed apnea a diagnosis of "CompSAS/CSDB" makes. I recognized that one mixed event was just the juncture between two issues I appear to have.
The obstructive sleep apnea runs in my mothers family. I am pretty certain cardiovascular complications from untreated obstructive sleep apnea was the cause of my grandfathers early death.
The central sleep apnea appears to be growing over time. I clearly have symptoms of problems with the cerebellum and issues with my autonomic nervous system. The central apnea (waking and asleep) as well as dysregulation of the normal sleep cycle (as the spontaneous arousals seems to indicate) are just two of the most recent examples.
-SWS wrote:... So this information is for the brand spankin' newcomers ...
Shoot, even an old timer appreciates a good explanation. I've read and reread articles. You concisely explained the differences. I certainly appreicate it.
-SWS wrote:... However, you described progressive biological undershoot culminating in central apnea. The CompSAS/CSDB pattern typically intersperses initial breathing overshoot as well as subsequent undershoot --- with highly cyclic oscillatory characteristics regarding that unsteady tidal-flow volume sequencing. And quite often that recurring sequence culminates in one or more central apneas. ...
In my case there appears to be no real overshoot effort. I just stop. Often I resume breathing with no overshoot. Just a fairly normal breathing rate. As I sit here typing this, I am doing that. I take a deep breath, then resume breathing normally for a while. I stop monitoring it and my breathing goes shallower and shallower, stops, take a deep breath, repeat. Unfortunately while asleep the apnea can last for quite a long time. As I've noted my BiPAP unit would turn off automatically. The algorithm of the unit would assume no one was wearing the mask, since there was no respiration. Even after I disabled the Auto Off feature, my body / brain would kick me with a shot of adrenaline. I awaken with an instant fight or flight response. Heart racing. I try to calm myself and go back to sleep. Over and over and over again. I would not wish this on anyone!
-SWS wrote:... So while you might have at least some
pathophysiology in common with typical CompSAS/CSDB, your
pathogenesis clearly differs ...
Exactly. I am fairly certain that several factors led my neurologist / sleep specialist to conclude this is due to dysregulation of breathing as a result of the Sporadic Olivopontocerebellar atrophy (OPCA). It might actually indicate my diagnosis might be better lumped under Multiple Systems Atrophy (MSA) than just Sporadic OPCA. Those factors? (1) Abnormal ABG and PFT results, (2) the presence of sleep onset central apneas, (3) central apneas during NREM sleep, (4) the lack of pronounced hyperventilation to accompany the hypoventilation, and (5) the CLEAR tendency for the breathing to stabilize during deep sleep and REM sleep.
My neurologist wants to reconfirm the Sporadic OPCA, but wanted to help me first attain better sleep.
Thanks. I will save and read this. I found the following interesting:
Finally, patients with waking hypercapnia primarily due to ventilatory control abnormalities (obesity hypoventilation syndrome, central alveolar hypoventilation) or neuromuscular disease may have central apneas during sleep as well. This is likely a product of the high plant gain in such patients (Figure 5A) or an absence of ventilatory drive during sleep when respiration is largely dependent on these chemical control mechanisms (63, 64).
In this case "central alveolar hypoventilation" (but not "congenital central hypoventilation syndrome (CCHS)" aka "Ondine's curse") makes sense. Though I am definitely morbidly obese, OHS does not seem to apply, since my breathing stabilizes during REM sleep. With OHS, the breathing tends to be less stable during REM sleep. For other readers, see the following disucssion of Hypoventilation Syndromes:
http://emedicine.medscape.com/article/304381-overview
My neurologist had iniitially mentioned Ondine's Curse (CCHS) or Pickwickian Syndroms (OHS), but dropped OHS after the sleep study indicated better respiration during REM sleep. Not that he feels I inherited CCHS. The "Sporadic" in "Sporadic OPCA" indicates this does not appear to be an inherited disorder. Also, my sleep fell apart AFTER I had lost almost 40 pounds not after I had gained weight. Now with better sleep I will be able to drop the weight again.
So, I will start working with this neurologist to pin down my neurological issues. Sporadic OPCA is essentially a "holding pattern" diagnosis. We know something is wrong. We know where I have problems - based on the symptoms. We just don't know quite yet which direction it will ultimately head.
And I started to work with him to document the potential need for Long Term Disability, since I also have other issues that reduce my ability to function adequately in my job. I have more and more problems with sensory input overload. This disables my ability to function in busy environments (offices, airports, etc.). So, I will be exploring this more to see what I can do to manage the situation.
