A medication used to manage Type 2 diabetes has been found effective in treating sleep apnea.

The worldwide clinical trial demonstrates that tirzepatide significantly lowers breathing interruptions during sleep, a key indicator of the severity of a patient's obstructive sleep apnea (OSA).

Tirzepatide is one of the class of blockbuster GLP-1 medicines, sold as Mounjaro to fight diabetes and as Zepbound to help with weight loss.

"This study marks a significant milestone in the treatment of OSA, offering a promising new therapeutic option that addresses both respiratory and metabolic complications," said study leader Dr. Atul Malhotra, director of sleep medicine at UC San Diego Health.

OSA is characterized by repeated episodes of irregular breathing during sleep due to total or partial blockage of the upper airway. It can result in reduced oxygen levels in the blood and has been linked to an increased risk for high blood pressure, heart disease and other heart-related complications. 

More than 900 million people worldwide are believed to have OSA, and the 469 participants in this study were recruited from the United States and eight other countries. All were clinically obese and had moderate-to-severe sleep apnea.

Some used continuous positive airway pressure (CPAP) treatment, in which a machine maintains an open airway during sleep. All were given 10 or 15 milligrams (mg) of tirzepatide or a placebo. 

Over the course of one year, patients who used tirzepatide had a significant drop in breathing interruptions during sleep. Their improvement was much greater than that seen in the placebo group. Researchers said some patients might no longer need CPAP therapy.

The findings, published June 21 in the New England Journal of Medicine, add to evidence that a drug targeting both apnea and obesity is better than treating either condition on its own. Researchers said the drug therapy improved other aspects related to OSA, such as improving weight. Some patients, however, had mild stomach issues.

For patients who hate wearing a CPAP mask over their nose and mouth when they go to bed, the findings could be welcome news.

"This breakthrough opens the door to a new era of OSA management for people diagnosed with obesity, potentially transforming how we approach and treat this pervasive condition on a global scale," Malhotra said in a UC San Diego Health news release.