Toronto: During a flight, people with severe obstructive sleep apnea (OSA) might be at a greater risk of cardiac stress than healthy people, according to a study. Researchers compared oxygen levels and ventilation of healthy people with those suffering severe OSA during simulated flight conditions.

"We predicted that OSA patients would have a much sharper fall in oxygen levels because they might not increase their breathing as much," said Leigh Seccombe, who led the study.

"We found that patients with OSA do have a lower blood oxygen level before and during flight stimulation, but that the change in oxygen was similar. We also found that their breathing intensity increases at about the same rate as it does in healthy people," she added.

But "the work they do to run the core range of body functions (heart, lungs, brain) is much greater under cabin conditions," explained Seccombe.

"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," said Seccombe.

"Half of the patients with OSA would require supplemental oxygen in-flight if current guidelines (for those with lung disease) were strictly followed if these results are typical."

The findings of the study were presented on Sunday at the American Thoracic Society's annual meeting here. IANS