It is not clear that AMBIEN changes the architecture of sleep. Compared to the other benzodiazepines. any changes to REM sleep are minimal or not at all. Studies done have not been consistent.
Also, let me note that since my pulmonologist prescribed ambien 5 mg my (AHI) have improved significantly

I HAVE OSA AND USE A CPAP MACHINE NIGHTLY. MY AHI IS USUALLY IN THE RANGE OF 10 TO 20. THEN I ADDED 5 MG OF AMBIEN AND IT’S NOW ALMOST ALWAYS NOW 0 TO 5! I SPOKE TO MY PULMONOLOGIST AND HE SAID THAT AMBIEN ACTUALLY IMPROVES APNEA, ESPECIALLY CENTRAL SLEEP APNEA. That me, because I was under the impr...