There are many things that we do not understand about obstructive sleep apnea.  This is particularly true for women and men at least 60 years of age, where approximately 20-40% are in the moderate to severe sleep apnea range.  Although sleep apnea is very common among older adults (note: age is just a number, but medical studies often group individuals aged 60 years or older as being “older adults”), few studies have examined the consequences of sleep apnea in this group specifically.  The need to include older adults in studies is critical for many reasons, including that this group is a growing share of the population worldwide and that sleep apnea may be like other medical “conditions” that are considered by some as normal in older adults (hypothyroidism, high blood pressure).

In people of all ages, obstructive sleep apnea is typically more pronounced during rapid eye movement (REM) sleep, the stage of sleep during which dreams occur.  During REM sleep, the muscles in your body, other than those that control eye movement, are at their most relaxed (inactive) state.  Because your throat is basically a tube surrounded by muscles, this muscle relaxation is one reason that sleep apnea is at its worst during REM sleep for many patients.  It is fairly common for people to have normal breathing patterns during non-REM sleep but sleep apnea in REM sleep (also called REM-related OSA).  The overall apnea-hypopnea index can be elevated, with the abnormalities limited to REM sleep, and it is unclear whether REM-related OSA has the same harms related to health and sleep quality.

Should we worry about REM-related OSA?

No studies have explored the potential health effects of REM-related OSA.  However, some large studies have examined the possible behavioral consequences of REM-related OSA, like sleepiness and quality of life.  One of these is the Sleep Heart Health Study, in which almost 5700 people across a wide age range underwent sleep studies and completed a number of questionnaires.  One of the research papers from this study showed that REM-related OSA was not associated with sleepiness or lower quality of life.

The March 2013 issue of the Journal of Clinical Sleep Medicine includes a study of REM-related obstructive sleep apnea in older men on which I was a coauthor.  This study evaluated 2700 older men in a study started to determine risks of osteoporosis-related fractures which was then expanded to include sleep-related topics.  Individuals with REM-related OSA had less sleep time and less REM sleep, but there was no relationship with sleepiness, quality of life, or depressive symptoms.  This study emphasizes the fact that treatment of sleep apnea requires consideration of the entire patient

My view of REM-related OSA

The bottom line is the it is unclear how important it is to treat REM-related OSA.  Some patients with REM-related OSA experience sleepiness, fatigue, and poor sleep quality that improves with treatment, and some do not.  My personal experience is that many patients with REM-related OSA have symptoms and will also have improvement with treatment, but it is important to rule out other sleep problems like insomnia or inadequate sleep time (sleeping less than 7-8 hours per night).  By treating patients as more than just numbers, we can focus on their concerns and not a specific number from a sleep study like the apnea-hypopnea index.  We develop a plan to address their symptoms rather than just searching for patients who have any evidence of sleep apnea and then rushing to treat that.  I require patients to obtain the full sleep study report so that I can look at specific findings and determine whether their sleep apnea may be limited to REM sleep, the time sleeping while laying on their back, or have other important features.  Integrating these reports, a full assessment of their symptoms and medical health, and my physical examination, we develop individualized treatment plans that are right for them.

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