By Virginia Gurley, MD, MPH
MB (Marc Braman, MD, MPH):
“Asthma & Sleep.” And we are joined again by our sleep and circadian rhythm expert, Dr. Virginia Gurley. Welcome back, Dr. Gurley.
VG (Virginia Gurley, MD, MPH):
Thank you, Dr. Braman.
MB:
Asthma affects many people, including both children and adults, and most commonly recognized symptoms of wheezing, shortness of breath, you can also have coughing. What do we know about how sleep affects asthma?
VG:
Surprisingly, there aren’t many studies on how sleep affects asthma. Studies have shown that during sleep a key measure of how well we breath, called forced expiratory volume, is decreased, which means air doesn’t flow out the lungs as easily and breathing is not as effective as when we’re awake. It’s not clear whether the usual decrease in forced expiratory volume that occurs during sleep is greater in people with asthma, but it does seem to contribute to worsening of symptoms during sleep, and this is called nocturnal asthma.
MB:
What about how much sleep a person gets, does that have an effect on asthma?
VG:
Here again, there aren’t many asthma-specific studies, but quite a few studies have shown that getting less than 6 hours of sleep increases inflammation, and since inflammation in the airways is a big part of asthma, it makes sense that not getting enough sleep could make asthma worse.
MB:
That makes a lot of sense. How about the other side of the coin, what do we know about how asthma affects sleep?
VG:
Here, we have many more studies, and unfortunately, most of them show that asthma can have a very negative effect on sleep, especially sleep quality. As we discussed a few minutes ago, asthma symptoms tend to be worse during sleep, and in fact, there are many people with asthma who only have symptoms of asthma during sleep. Now, not all coughing at night is asthma. People who have stomach acid reflux often have nighttime coughing and wheezing. Clearly, anyone that regularly experiences nighttime coughing, wheezing and difficulty breathing, is not going to get restful, restorative sleep. Sadly, many people don’t tell their doctor about their chronic nighttime coughing, and then their asthma, or their gastric reflux, goes undiagnosed and untreated.
MB:
It sounds like good management of sleep-time asthma symptoms can provide a great win-win.
VG:
That’s right, fewer nighttime symptoms allows for better quality sleep, which may lead to less airway inflammation, which leads to fewer asthma symptoms.
MB:
Excellent. Thank you so much, Dr. Gurley!
VG:
Thank you, Dr. Braman.
Breathing patterns during sleep in patients with nocturnal asthma. Morgan AD, Rhind GB, Connaughton JJ, Catterall JR, Shapiro CM, Douglas NJ. Thorax. 1987 Aug;42(8):600-3.
Sleep and immune function. Besedovsky L, Lange T, Born J. Pflugers Arch. 2012 Jan;463(1):121-37. doi: 10.1007/s00424-011-1044-0. Epub 2011 Nov 10. Review.
ABC of sleep disorders. Catterall JR, Shapiro CM. Nocturnal asthma. BMJ. 1993 May 1;306(6886):1189-92. Review.
