Flying may tax the hearts of apnea sufferers
NEW YORK (Reuters Health) - People with severe obstructive sleep apnea taking commercial airline flights may be at greater risk of adverse events from stress on the heart than healthy people, researchers warned at the American Thoracic Society's 2008 meeting in Toronto.
Obstructive sleep apnea, or OSA, occurs when soft tissues in the airways collapse during sleep and temporarily block breathing. This can happen dozens of times an hour, leading to daytime sleepiness and eventually to increases in blood pressure.
In a study, Leigh M. Seccombe, of Concord Repatriation General Hospital in Sydney, Australia, found evidence that patients with OSA may experience higher heart rates and increased bodily need for oxygen during flights compared with healthy people.
Seccombe and her colleagues compared oxygen levels in the blood and ventilation rates in 10 healthy people and 22 people with severe OSA during simulated flight conditions replicating the oxygen and air pressure levels experienced during commercial flights.
"It is normal for the rate of breathing to increase when air pressure falls," Seccombe explained in a statement. "We found that (for patients with OSA) their breathing intensity increases at about the same rate as it does in healthy people."
However, the physiological stress and demand for oxygen was increased in people with OSA.
"In short, the work they do to run the core range of body functions (heart, lungs, brain) is much greater under cabin conditions," said Seccombe, who is currently part of a group working on guidelines that will help doctors decide whether their patients are at risk from air travel.
"We addressed OSA because it is becoming so much more common as obesity increases and there are greater numbers of obese passengers on commercial flights," Seccombe said.
If the results of the current study are typical, "half of the patients with OSA would require supplemental oxygen in-flight if current guidelines (for those with lung disease) were strictly followed," she noted.