Well, I believe it's the cessation of breathing itself which is the primary detriment. That is, the lack of oxygen intake. This as opposed to the sleep disturbance caused by the sudden reaction to this detriment, with the characteristic "snort".
I stand ready to be corrected.
Never dropping into REM sleep has a very bad effect on your mental and physical health.
It might even be the root cause of some mental problems.
Even in people without sleep apnea are bad tempered and foggy when they are short of sleep.
Living that way for years begins to wear you down, laying in mental pathways, that even after the sleep problem has been corrected can still cause health problems.
Sleep and dreaming is not well understood even now but we do know that it does far more than rest tired muscles.
Its all working together. You are trying to sleep, obstructions in your airway wont allow it and you stop breatrhing. When you stop breathing while sleeping - your body does amazing things to keep you alive and try to wake you up.
Yes, the “snort’ is when you start breathing again but thats only an audible alarm as to what is happening in your body. Your body trys to wake you by shocking you, scaring you into being startled awake, becasue, HEY YOU ARE NOT BREATHING!
Every time you hear the “snort” this happens - Your abdomen muscles contract violently and compress the space around your chest and heart (* this also weakens and stretches the bag around the heart and makes you even more susceptible to congestive heart failure that is the hallmark of sleep apnea) , to make you forceable exhale and to bump your blood pressure up so your mind will wake up and you will start breathing again. During this you typicaly change from REM sleep stage 2 or 3 to stage 1 and will probly never reach stage 4 or 5 ever again without CPAP help.
This action has only taken a few seconds but has interuppted your sleep. Now imagine your body doing this over 200 times in one hour, all night long, every night of your life.