A new study indicates that those who have sleep apnea may have an increased risk of developing pneumonia.
Those with sleep apnea have disrupted sleep, caused when the upper airway becomes obstructed by soft tissue, which cuts off oxygen. This can happen hundreds of times per night. Several types of heart disease and cognitive impairment have been linked to the condition. Those who have obstructive sleep apnea have a higher risk of aspiration while sleeping. The National Sleep Foundation says that around 18 million Americans suffer from sleep apnea.
Several previous studies have examined the connection between sleep apnea and pneumonia, but this study is the largest yet to do so.
"This study showed that sleep apnea is an independent risk factor for incident pneumonia," wrote Dr. Vincent Fi-Yong Su and Dr. Kun-Ta Chou of the department of chest medicine at Taipei Veterans General Hospital in Taiwan. "Our results also demonstrated an exposure-response relation in that patients with more severe sleep apnea may have a higher risk of pneumonia than patients with sleep apnea of milder severity."
For their study, the researchers tracked 34,100 patients over the course of 11 years from 2000 to the end of 2010. Of those 34,100 patients, 6,816 of those had sleep apnea and 27,284 did not. The researchers found that nine percent of those with sleep apnea developed pneumonia, compared with fewer than eight percent among those who did not have the disorder. The risk was higher among those patients who used continuous positive airway pressure (CPAP) therapy, which is considered the gold standard for treating sleep apnea. The research was published in the Canadian Medical Association Journal.
Those who developed pneumonia were older and also had more comorbidities like diabetes, heart disease, dementia and other conditions. The researchers said that the higher incidence of pneumonia in those with sleep apnea could be due to an increased risk of aspirating contents or liquid from the throat.
The study showed an association between sleep apnea and pneumonia risk. However, it did not prove a cause-and-effect connection and the researchers did not explore the mechanisms connecting sleep apnea and pneumonia.
In October 2013, Medical News Today reported another study from researchers at the University of California Los Angeles suggesting that sleep apnea may pose a hidden threat to women. They found that though women with sleep apnea might appear healthy, they have have subtle symptoms, leading to frequent misdiagnosis of the condition.
