Obstructive Sleep Apnea Increases Inflammation in COPD
Background: Obstructive sleep apnea (OSA) is a common condition that affects about 5% of adults over the age of 40 years. Apnea is a medical word that means to stop breathing for at least 10 seconds. This can occur during sleep at night when the muscles of the throat relax and block the flow of air into and out of the lungs. The person then wakes up and starts to breathe again. This process of stopping breathing and waking up to start breathing can occur hundreds of times during the night and cause poor sleep quality.
In one study 66% of those with COPD who enrolled in pulmonary rehabiliation tested positive for obstructive sleep apnea (Ann Am Thorac Soc. 2015;12(8):1219-25. dos: 10.1513/AnnalsATS.201407-336OC ). Some of these individuals with both COPD and OSA (called overlap syndrome) had pulmonary hypertension (high blood pressure in the blood vessels of the lungs).
Study: In the September 2015 issue of the journal Sleep Medicine (volume 16, pages 1123-1130), Wang and colleagues studied whether OSA affects inflammation in the lungs of those with COPD. They studied 47 individuals with overlap syndrome (both COPD and OSA) along with 28 with moderate to severe COPD. A tube was passed into the mouth and into the lungs (called bronchoscopy) and fluid was injected and then suctioned to obtain samples of cells from the lungs.
Results: Those with the overlap syndrome had more inflammation (neutrophils, tumor necrosis factor-α, and interleukin-8) in the lungs than those with COPD alone. The tumor necrosis factor-α was significantly correlated with the percentage of nighttime spent with the oxygen level less than 90%.
Conclusion: OSA increases inflammation in those with COPD.
My Comments: Inflammation in the lungs is considered “bad” for those with COPD because it can: 1. can increase narrowing of the airways (bronchoconstriction), 2. lead to damage in the lungs, and 3. increase the risk of sudden worsening (a COPD exacerbation).
Typical symptoms of OSA are snoring, stop breathing during sleep (ask your sleep partner about this), fatigue, and daytime sleepiness. I encourage you to ask your health care provider about OSA if you have any of these symptoms. A sleep study is performed to diagnose OSA. Treatments are available that can help keep your throat open when you sleep and prevent drops in your oxygen level during sleep. This can also lead to improvement in our COPD and quality of life.