Catching On to the Impact of REM Sleep.
In our research over the years, and in my new book, LIFE SAVING SLEEP, we emphasize the critical nature of consolidating REM sleep in our patients with sleep disordered-breathing. We found those with longer REM sleep intervals reported the best sleep quality and the most daytime improvements in mood and energy. To achieve these results, the advanced PAP devices such as auto-bilevel or ASV fared far better than CPAP mode. Prior posts and research discuss these PAP machines.
New research published along with an editorial about the study report on the severity of sleep apnea during REM sleep. The key finding is a worse apnea-hypopnea index (sleep breathing events) in REM, particularly during the morning hours of sleep, is linked to worse hypertension (high blood pressure).
The big reason the finding is so clinically important is most sleep apnea patients using CPAP cannot average more than 4 to 6 hours of sleep. Yet, REM sleep is most pronounced in the final third of the night, more often than not between the 6th and 8th hours of sleep. In other words, a CPAP user is frequently not treating their most severe sleep apnea events. Instead, many remove their masks after 5 to 6 hours and then fall back asleep without the mask. If so, they may be suffering their worst sleep breathing events with no treatment to intervene. It’s also possible CPAP is ineffective in treating the most severe breathing events, and so once the individual enters REM, the patient wakes up from poorly treated sleep apnea. Afterwards, instead of going back to sleep with the mask, they just go back but no mask.
In our work with advanced devices, we found many patients were averaging more than 6 hours, which means many were hitting the 7 or 8 hour mark. In all likelihood they were getting a better REM response during these final hours.
Last, a major study in Europe a year ago revealed longer use of CPAP clearly demonstrated improved cardiovascular outcomes, and once again the suggestion is more REM sleep was effectively treated in these study patients. When you follow a lot of older research, you will see many reports on how CPAP did not help cardiovascular outcomes, but nearly all of the studies showed lower averages of use, like 4 to 5 hours, some even lower.
Putting it all together, the reason longer hours of sleep with PAP is valuable appears to be this link to addressing the severe breathing events in REM sleep. In our experience most patients will get more REM with advanced devices, and they may discover they only need 6 or 7 hours of sleep instead of the conventionally touted 8 hours to still achieve a great deal of REM each night.