• Posted September 11, 2023

Have Sleep Apnea? CPAP Machine May Help Save Your Life

Millions of people who suffer from sleep apnea go to bed at night with a motorized device called a CPAP machine.

Now, two new studies confirm the treatment has significant benefits not just on quality of sleep, but also for keeping people's hearts healthy.

Together, the studies may offer more reasons to endure the not-always-comfortable treatment known as continuous positive airway pressure (CPAP) that keeps people breathing properly through the night.

"The results are striking,"said Dr. Jordi de Batlle, co-author of one of the studies.

Over the study period, patients who stuck with CPAP treatment reduced their risk of death from heart disease by 36%. And they had a 40% lower risk of death from any cause, his study found.

Previous research has had mixed results, said de Batlle, who is with the Biomedical Research Institute of Lleida in Spain.

His team found that CPAP treatment could help many obstructive sleep apnea (OSA) patients by preventing heart disease and stroke, after already helping reduce sleepiness and improve quality of life.

To test this, the researchers tracked down more than 3,600 OSA patients in Catalonia who had stopped using CPAP in 2011. The investigators compared them to an equal number of patients who continued to use their CPAP until at least 2015 or death.

Besides lower odds for death, those who continued to use their CPAP had an 18% lower risk of hospitalization due to heart disease.

De Batlle acknowledged there could be some biases that magnify the impact. Yet the data are also in line with some past research, he noted.

Another expert said the study used real-world patients who may have been excluded by safety criteria in early clinical trials. "And, indeed, they found a really dramatic lower risk of cardiovascular death,"noted Dr. Janet Wei, a cardiologist in the Smidt Heart Institute at Cedars-Sinai in Los Angeles.

"I do commend the investigators for studying this really important issue of obstructive sleep apnea because we do have evidence that sleep apnea is certainly a risk factor for cardiovascular disease, whether it's hypertension or coronary heart disease, angina, atrial fibrillation, heart failure, et cetera,"Wei said.

But it is still important to remember that the study was observational and retrospective so can't be conclusive, she added.

"We can't be convinced that CPAP necessarily reduces (cardiovascular disease), but I think it's certainly very thought-provoking and kind of reassuring that patients should try to stay on their CPAP treatment,"Wei said.

How could a CPAP machine make such a big difference in death and disease?

While the study isn't designed to answer that question, it's known that when someone with sleep apnea sleeps, their throat muscles relax.

This causes the airway to narrow or close off completely. Breathing is temporarily interrupted.

"These breathing pauses can lead to a decrease in oxygen levels in the blood and disturb the quality of sleep, and potentially cause several conditions, including high blood pressure, cardiovascular diseases, cerebrovascular diseases, metabolic disorders and even cancer. Therefore, reversing the situation by using CPAP could potentially reduce all the negative effects associated with sleeping poorly and suffering intermittent [oxygen deprivation],"de Batlle said.

Losing weight is typically the first recommendation for sleep apnea patients who are overweight or obese, de Batlle said. When weight loss isn't enough to improve the sleep disorder, CPAP is the gold standard.

The findings from the two studies are scheduled for presentation this week at a meeting of the European Respiratory Society in Milan, Italy.

The other study compared the effects of CPAP and the weight loss medication liraglutide on coronary artery plaque volume.

In that proof-of-concept study, researchers found that CPAP may reduce coronary artery plaque volume in patients with sleep apnea. The weight loss medication did not appear to have the same impact.

However, the study was small, with just 30 patients who received one or both treatments for 24 weeks.

"Although this is a pilot study, meaning we cannot draw firm conclusions, we found improvements in some early signs of cardiovascular disease with CPAP treatment,"researcher Dr. Cliona O'Donnell, a registrar in respiratory medicine at St. Vincent's University Hospital and University College in Dublin, Ireland, said in a meeting news release. "This should now be evaluated in larger studies."

Wei said the second study is thought-provoking, but noted its small size.

As for why people might discontinue their CPAP treatment, Wei said some can't tolerate the machine or are too ill to wear it.

"The greatest challenge of management of obstructive sleep apnea is the tolerance of the treatment,"Wei said.

An option would be using different CPAP apparatus, such as a nasal CPAP.

Findings presented at medical meetings should be considered preliminary until published in a peer-reviewed journal.

More information

The U.S. National Institutes of Health has more on sleep apnea.

SOURCES: Jordi de Batlle, senior researcher, translational research in respiratory medicine, Biomedical Research Institute of Lleida, Spain; Janet Wei, MD, cardiologist, Smidt Heart Institute, Cedars-Sinai, Los Angeles; European Respiratory Society International Congress, Milan, Italy, Sept. 9 to 13, 2023