The largest sleep apnea study shows CPAP improves life quality but without any cardiovascular benefit
The largest sleep study ever undertaken has found that the leading therapy for obstructive sleep apnea (OSA), Continuous Positive Airway Pressure (CPAP), does not reduce recurrent strokes and heart attacks in people with cardiovascular disease but does significantly improve their quality of life and mood.
Researchers from Flinders University and The George Institute for Global health, who published their findings in The New England Journal of Medicine, spent more than four years studying 2,700 people with OSA and cardiovascular disease from seven countries who used CPAP machines to manage their OSA.
Flinders University’s Professor Doug McEvoy, who presented the findings at the European Society of Cardiology Conference today, said he was surprised that his team didn’t find cardiovascular benefits from CPAP usage but he was particularly encouraged by the significant impact on mood and reported wellbeing.
“We were surprised not to find a reduction in cardiovascular events from CPAP usage, however patients who used the machines for a minimum of three hours a night reported significant improvements in their wellbeing from their snoring, mood, quality of life and the amount of time they needed to take off work due to sickness,” said Professor McEvoy.
“We knew that people who have OSA have an increased risk of cardiovascular disease and wanted to see if we could help reduce the burden of cardiovascular disease by treating this sleep disorder. While we didn’t show that, we believe our findings will be of great value to healthcare providers and encouraging news for tens of millions of OSA sufferers worldwide.”
Co-author Professor Craig Anderson, from The George Institute for Global Health, said CPAP machines clearly improved the lives of people with sleep disordered breathing.
“As well as raising the risk of having a heart attack or stroke, OSA causes a whole host of other problems such as lethargy, daytime napping, poor thinking, and impacts on relationships through excessive snoring,” he said.
“We have shown that CPAP can help improve the lives of people with CPAP, which is significant, and of real benefit to people who suffer from sleep disordered breathing.
“More research is now needed on how to reduce the significant risk of suffering a heart attack or stroke for those who suffer from sleep apnea.”
• Trial participants were recruited from over 80 clinical centres in China, Australia, New Zealand, India, USA, Spain and Brazil and were predominantly overweight and older males, habitual snorers and had moderately severe OSA.
• Out of the 2700 people on the trial, 1346 were assigned to receive CPAP.
• The study found 17 per cent of participants receiving CPAP treatment and routine care went onto develop serious cardiovascular events such as stroke and heart attack, compared to 15.4 per cent who received routine care alone.
• The researchers also found that CPAP treatment produced a 20% improvement in severe depression, a two thirds reduction in severe sleepiness, and 20% less days lost from work.