People who suffer from sleep apnea - a serious condition where the upper airway is obstructed during sleep - appear to have a higher risk of pneumonia, according to a new study from Taiwan and published in the Canadian Medical Association Journal.
Obstructive sleep apnea - often shortened to sleep apnea, as it is the most common form - is characterized by disturbed sleep caused by soft tissue obstructing the upper airway, cutting off the oxygen supply. This can happen hundreds of times a night. The condition has been linked to heart disease and cognitive impairment.
According to the National Sleep Foundation, about 18 million Americans have sleep apnea.
While several studies have already looked at links between sleep apnea and pneumonia, this latest investigation is the largest to do so.
Dr. Vincent Yi-Fong Su, of Taipei Veterans General Hospital in Taiwan, and colleagues selected over 34,000 patients from Taiwan's National Health Insurance Research Database (nearly 7,000 patients with sleep apnea matched to over 27,000 people without sleep apnea).
They followed the participants for 11 years, from the beginning of 2000 to the end of 2010, and compared occurrence of pneumonia in the two groups.
Sleep apnea appears to be an independent risk factor for pneumonia
They found the group with sleep apnea had a 1.20-fold increase in incident pneumonia, compared with the group without sleep apnea (9.36% developed it in the apnea group versus 7.77% in the controls).
A study suggests that people with sleep apnea - a condition where the upper away is obstructed during sleep - may have a higher risk of pneumonia.
The team concludes that sleep apnea appears to be an "independent risk factor for incident pneumonia," and notes they also found an "exposure-response relation," meaning that patients with more severe sleep apnea appeared to have a higher risk of developing pneumonia than patients with milder forms of the condition.
While they did not explore the mechanisms linking sleep apnea with pneumonia, the researchers suggest it could be that people with sleep apnea are more likely to aspirate liquid from the throat into the lungs.
Another reason could be a weaker immune system, which can result from frequently disturbed sleep.
In October 2013, Medical News Today reported another study led by researchers at the University of California Los Angeles that suggested sleep apnea may hold hidden dangers for women. They found women with sleep apnea may appear healthy, but they have subtle symptoms, which means the condition is often misdiagnosed.