When Weight Loss Medication Meets Sleep Apnea

Obstructive sleep apnea, where the airway repeatedly narrows or closes during sleep, is common in people living with excess weight. Researchers have long known that weight and sleep apnea are linked, which made it a natural question for the new GLP-1 and GIP medications. This guide walks through the first large trials built to answer it. It is general education, not medical advice.

Why weight and sleep apnea go together

Excess weight can mean more tissue around the neck and upper airway, which can make it easier for the airway to collapse during sleep. Sleep apnea is measured with the apnea-hypopnea index, or AHI: the number of breathing pauses and shallow breaths per hour of sleep. Moderate to severe sleep apnea is generally 15 or more events an hour. Losing weight has long been recognized as one way to reduce it, though not everyone’s airway responds the same way.

The SURMOUNT-OSA trials

SURMOUNT-OSA was a pair of 52-week, randomized, placebo-controlled phase 3 trials of tirzepatide, a medication that acts on both GLP-1 and GIP receptors. Participants were adults with obesity and moderate-to-severe obstructive sleep apnea. In the first trial, people were unable or unwilling to use positive airway pressure (PAP) therapy. In the second, they were using PAP and planned to continue. The results were published in the New England Journal of Medicine in 2024.

What was reported

• Fewer breathing events. At 52 weeks, the average AHI fell by about 27 events an hour in the first trial and about 30 in the second, compared with roughly 5 to 6 events an hour in the placebo groups. Starting AHI averaged about 50 events an hour.
• Substantial weight loss. Average weight loss was about 18 to 20 percent of body weight on tirzepatide, compared with 1 to 2 percent on placebo.
• Some participants no longer met the criteria for sleep apnea. Around 43 to 52 percent of those at the highest dose reached criteria for disease resolution, as defined by the study.
• Side effects were mostly digestive. The most common were gastrointestinal and generally mild to moderate, in line with what was seen in other trials. Our guide to side effects in the big GLP-1 trials covers those in more detail.

How to read the numbers

• It was a medication study with weight loss built in. The trials show that a drug that produces large weight loss also reduces sleep apnea severity. They cannot separate the effect of the drug from the effect of the weight lost.
• The figures here come from the published trial summaries. We have reported them as described in the trial results and conference abstracts. For exact values and confidence intervals, read the paper itself.
• A year is a year. The trials do not tell us what happens over many years, or after stopping. Our guide to stopping a GLP-1 medication looks at that question.
• Everyone is different. People with sleep apnea have different anatomy and different causes, and not everyone with sleep apnea has obesity.

What this does not mean

This is not a reason to stop using a CPAP machine or any other treatment. Sleep apnea can affect heart health, blood pressure and daytime alertness, and treatment decisions belong to a sleep specialist or primary care clinician. In the second trial, people stayed on PAP therapy while taking part.

If you think you may have sleep apnea

• Know the common signs. Loud snoring, gasping or choking at night, unrefreshing sleep, morning headaches and daytime sleepiness are common clues, and a partner may notice them first.
• Ask for an evaluation. A clinician can arrange a home or lab sleep test.
• Bring up weight honestly. If weight is part of the picture, a clinician can discuss the full set of options with you. Our sleep basics guide covers everyday habits that support better rest.

The takeaway

These trials added a new, well-designed piece of evidence: for adults with obesity and moderate-to-severe sleep apnea, a medication that leads to substantial weight loss also led to a large drop in breathing events. It is promising, and it belongs in a conversation with a clinician, alongside the treatments that already work.

Sources

• Malhotra A, Grunstein RR, Fietze I, et al. Tirzepatide for the treatment of obstructive sleep apnea and obesity. New England Journal of Medicine, 2024 (SURMOUNT-OSA).
• Eli Lilly and Company. SURMOUNT-OSA topline results and conference abstract (Malhotra, Grunstein and colleagues), 2024.
• Figures were taken from the topline release and conference abstract; check the published paper for exact values.