At home sleep study results

I finally had my followup from my at home study last month. I'm still very fatigued despite the readings on my machine indicating my AHI is almost always below 1. My sleep doctor had me do the at home study to see if the machine readings were accurate. While they didn't show any apneas they did show a lot of respiratory disturbances. Basically, she said for some reason I'm still working really hard during the night to breath. She suggested doing a study in a sleep center so we can figure out exactly what's going on and as long as insurance will cover it I'm going to go ahead and do it. I can't figure out why I'd be struggling to breath even with the machine. She asked about a deviated septum or lots of nasal congestion. I know I tend to wake with a little congestion when I don't use my machine, but when I use it I don't notice any. And my ENT once said I had a "very slight" deviated septum but didn't seem concerned about it.

I still wake up a lot during the night. That never changed after starting the CPAP and I don't know why I'm waking. I wake up and feel fully awake quite a few times during the night, but fall back asleep when I realize it's not morning yet and then as it gets closer to morning I'm exhausted and feel like I hardly slept at all. So maybe they'll find there is still a reason that this is happening. Fingers crossed.

Just curious if anyone has had this "respiratory disturbance" thing come up on a home study and if they figured out what it was.

Restless leg syndrome is the most likely cause for what you describe.

It would depend what she meant by "respiratory disturbance"? It could be a cough, sneeze or centrals or a few other things. She is the one with the data of your sleep in front of her. Assuming the machine had a data card in it.

I am a dentist working in dental sleep medicine. What you describe sounds like Upper Airway Resistance Syndrome(UARS) to me. People have the mistaken impression that, if they are not having any apneas, things are necessarily all right. That is a mistake. When people have apneas or hypopneas, they create arousals from deep sleep that make you tired. In UARS, there is still an abnormally high resistance to air flow in your breathing passages. This makes your body work so hard to breathe that, again, it awakens you from deep sleep and makes you feel very tired. These arousals are shorter than the ones from apneas and hypopneas and are called spontaneous arousals. These are recorded in most lab sleep studies and may or may not be recorded in home sleep studies. Arthur B. Luisi, Jr., D.M.D.

Is there a physiological reason for high resistance to air flow? Some physical characteristic that causes this issue or is the syndrome not understood well enough to pinpoint cause?

Certainly, It is different factors in different people and to different degrees. Some of the factors could be: deviated septum, enlarged nasal turbinates(little hills inside the nose), chronic rhinitis(nasal congestion) due to allergies and/or sinus problems, congenitally small nasal passages, enlarged tonsils, Macroglossia(big tongue) just like OSA, large, floppy soft palate and uvula(just like OSA), retognatha(small lower jaw), and others. The net effect is that the air is forced through a restricted airway system, the total pressure goes up, and it gets hard to breathe. Different people need different fixes, although both CPAP and oral appliances will sometimes overcome the resistance in a band-aid type of approach. Arthur B. Luisi, Jr.,D.M.D.