- Obstructive sleep apnea is a common disorder that causes people’s breathing to pause frequently during sleep.
- The condition leads to reduced oxygen levels, daytime sleepiness, and snoring, and increases the risk of more severe health problems, such as cardiovascular disease and dementia.
- Risk factors include overweight and obesity, age over 40, a thick neck circumference, smoking and alcohol consumption.
- Now, a study in patients with overweight or obesity has found that treatment with the latest weight-loss drug, retatrutide, greatly reduced sleep apnea symptoms.
There are no definitive figures for obstructive sleep apnea — a condition that causes people to stop breathing frequently during sleep — as it is often undiagnosed.
In the United States, sleep apnea affects up to one-third of adults, according to current estimates..
As well as causing daytime sleepiness, snoring and reduced oxygen levels, sleep apnea increases the risk of a number of health conditions including cardiovascular disease, type 2 diabetes, and dementia.
One of the main risk factors for sleep apnea is obesity, and with rising numbers of people with obesity, the prevalence of sleep apnea is likely to increase. Currently, the main treatment is a continuous positive airway pressure (CPAP) machine — a breathing device with a mask that is placed over the nose and mouth.
But the results of two phase 3 clinical trial now suggest that weight-loss drugs could be an effective treatment for sleep apnea.
In the trials — whose findings appear in The New England Journal of Medicine — treatment with an eleven weekly injection of retatrutide led to significant improvements in sleep apnea symptoms, with up to 50% of participants having only mild sleep apnea by the end of the trial.
Ron Grunstein, MD, PhD, lead author of the paper and Professor of Sleep Medicine at the Woolcock Institute of Medical Research, NSW, Australia, told Medical News Today:
“I think the finding is very important because there are many people with moderate to severe sleep apnea who are looking for alternative treatments to nasal CPAP and, as we emphasized in the paper retatrutide is providing an extra benefit for improving metabolic syndrome or metabolic dysfunction, which CPAP does not provide. The weight loss was substantial in the study and generally the reaction has been very positive.”
Mir Ali, MD, bariatric surgeon, a bariatric medicine specialist and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, who was not involved in this research, also commented on its findings.
“Obstructive sleep apnea (OSA) improving with weight loss is a well-established finding in morbidly obese patients, regardless of how the weight loss is achieved. In fact, OSA is often one of the first conditions to improve following surgical weight loss,” Ali told MNT.
Retatrutide tested in people with and without diabetes
Retatrutide is the latest in a group of medications that work on hormone receptors to control appetite and metabolism. It follows semaglutide (Ozempic/Wegovy), a glucagon-like peptide-1 (GLP-1) agonist, and tirzepatide (Mounjaro/Zepbound), which works on both GLP-1 receptors and glucose-dependent insulinotropic polypeptide (GIP) receptors.
In addition to working on both GLP-1 and GIP receptors, retatrutide also activates glucagon receptors, so is called a triple hormone receptor agonist. It is not yet licensed by the Food and Drug Administration (FDA) or any other authorities as it is still in phase 3 trials.
To investigate retatrutide’s effect on sleep apnea, researchers launched 2 trials — TRIUMPH-1-OSA in 243 people without type 2 diabetes and TRIUMPH-2-OSA in 448 people with type 2 diabetes.
All participants had overweight or obesity (body mass index greater than 27) and moderated to severe sleep apnea, with at least 15 breathing pauses per hour when sleeping.
For both the double-blind, randomized, placebo-controlled trials, researchers divided the participants into 4 treatment groups — placebo, 4 milligrams (mg), 9 mg or 12 mg of retatrutide, by weekly injection.
At the beginning of the study, at 24 weeks and at the end of the 80 week trial, participants stayed overnight in the sleep clinic for polysomnography to assess their sleep apnea.
The researchers recorded the changes in the apnea–hypopnea index (AHI), which records the number of pauses and partial pauses in breathing per hour.
Any dose of retatrutide led to improvements in sleep apnea symptoms
By week 24, all three doses of retatrutide led to symptom improvement. By week 80, in people without diabetes, the 4 mg dose decreased AHI by 23 events per hour, 9 mg by 34 per hour, and 12 mg by 32 per hour, against a reduction of just under 10 events per hour on placebo.
There were similar improvements in those with diabetes, with 4 mg leading to 20 fewer events per hour, 9 mg to 25 fewer per hour, and those on 12mg having 26 fewer apneas or hypopneas per hour, compared with 10 fewer on placebo.
Grunstein explained the findings:
“The improvements in sleep apnea symptoms and the objective effects are likely to be a result of the weight loss. There is no evidence that there is an independent direct effect of retatrutide on breathing control or some cause of sleep apnea.”
Might retatrutide become a routine treatment for sleep apnea?
Grunstein emphasized that further studies would be needed to verify the results, and future use would depend on price and availability, but that their findings were very encouraging.
And Ali cautioned: “The primary approach to treating obstructive sleep apnea is addressing the underlying condition, such as obesity. CPAP therapy is used for patients regardless of weight to improve sleep quality. For a medication to be considered a viable alternative to established therapies, studies would need to prove it improves OSA regardless of weight loss.”
“Increasingly, tirzepatide has become a treatment for sleep apnea, and retatrutide has some additional benefits,” Grunstein told Medical News Today.
“It is the first treatment that’s been shown to improve sleep apnea in patients with type 2 diabetes. I think the big thing is the metabolic advantage with retatrutide. This study converted a lot of people from type 2 diabetes to pre-diabetes and even to not having diabetes,” concluded the study author.
