GLP-1s and Sleep Apnea: What the SURMOUNT-OSA Trial Found

Obstructive sleep apnea (OSA) happens when tissue around the throat and upper airway relaxes and partially or fully blocks breathing during sleep, often dozens or hundreds of times a night. Excess weight — particularly fat around the neck and upper airway — is one of the strongest risk factors, because that tissue adds pressure that makes the airway more likely to collapse during sleep. Because GLP-1 medications produce substantial weight loss, researchers designed a dedicated trial, SURMOUNT-OSA, to test whether that weight loss translates into measurably less severe sleep apnea. The logic is straightforward: less tissue around the airway should mean fewer collapses per hour of sleep. But logic isn't proof, which is exactly why a randomized, controlled trial — rather than just inference from general weight-loss data — matters here. Before this trial, doctors had reason to suspect GLP-1s would help sleep apnea, but no dedicated data confirming it, or quantifying by how much.

SURMOUNT-OSA (Malhotra et al., NEJM 2024) enrolled adults with obesity and moderate-to-severe obstructive sleep apnea, randomizing them to tirzepatide or placebo over 52 weeks, in two parallel groups: one not using CPAP, one continuing CPAP therapy. In the group not using CPAP, tirzepatide reduced the apnea-hypopnea index (AHI) — the number of breathing interruptions per hour of sleep — by about 27 events per hour on average, roughly a 55% reduction. In the group continuing CPAP, the reduction was similar, around 30 events per hour, about a 63% reduction. Body weight fell by roughly 18-20% in the tirzepatide groups over the same period. Importantly, about half of participants on tirzepatide achieved AHI reductions large enough that they no longer met the clinical threshold for moderate-to-severe OSA by the end of the trial — a meaningful clinical shift, not just a statistical one. Participants also reported improvements in daytime sleepiness and blood pressure, both of which are commonly affected by untreated sleep apnea.

No — and the trial itself doesn't support that conclusion. SURMOUNT-OSA tested tirzepatide as an addition to standard care, not a replacement for it; one study arm specifically kept participants on CPAP throughout the trial and still saw meaningful benefit from adding tirzepatide. CPAP works immediately, every night, by mechanically keeping the airway open, while a GLP-1's effect on apnea builds gradually over months as weight comes off, and depends on continuing the medication. Some people may eventually be able to reduce CPAP pressure settings or, with their sleep physician's guidance, revisit whether they still need CPAP at all after significant, sustained weight loss — but that's a decision for a sleep specialist to make using a follow-up sleep study, not something to decide alone. Stopping CPAP prematurely, before apnea severity has actually been retested, carries real risk: untreated sleep apnea is linked to hypertension, irregular heart rhythms, and long-term cardiovascular strain.

Sleep apnea is more common in men overall, but the gap narrows sharply after menopause — some estimates suggest postmenopausal women's risk approaches that of men, compared to a much lower relative risk before menopause. Falling estrogen and progesterone are part of the explanation: progesterone in particular has a stimulating effect on breathing drive, and its decline may reduce that protective effect. Fat redistribution toward the abdomen and upper body after menopause — a well-documented shift — also adds tissue around the neck and airway, independent of total weight. Sleep apnea is additionally under-recognized in women in general, partly because the classic symptom profile (loud snoring, witnessed pauses in breathing, dramatic daytime sleepiness) was studied mostly in men; women more often report insomnia, fatigue, morning headaches, or low mood, symptoms that overlap heavily with both [perimenopause](/blog/the-34-symptoms-of-perimenopause-a-complete-checklist) and general midlife fatigue, and are easy to attribute to menopause alone rather than an independent sleep-breathing problem.

The starting point is a sleep study — either an in-lab polysomnography or a validated home sleep apnea test — which is the only way to actually measure your AHI and confirm a diagnosis; symptoms alone can't reliably distinguish sleep apnea from other causes of fatigue or [brain fog](/blog/menopause-brain-fog-why-memory-slips-and-what-helps). Signs worth raising with a doctor include loud snoring, a partner reporting pauses in your breathing, waking up gasping, morning headaches, unrefreshing sleep despite adequate hours in bed, and daytime sleepiness that interferes with driving or concentration. If you're already taking a GLP-1 for weight management and are later diagnosed with sleep apnea, it's worth knowing the SURMOUNT-OSA data exists — it may factor into your treatment plan alongside CPAP, not instead of it. And if you're managing sleep apnea risk factors alongside other cardiovascular concerns, it's also worth understanding your broader [heart disease risk in menopause](/blog/atrial-fibrillation-risk-in-menopause-what-changes-after-45), since untreated OSA and heart rhythm issues are closely linked.