Sleep apnea raises risk of cardiovascular events and death

New research to be presented at this year's European Congress on Obesity (ECO 2026, Istanbul, Turkey, 12-15 May) shows that those living with obstructive sleep apnea (OSA) have a 71% higher risk of cardiovascular events (CVEs) or death from any cause (all-cause mortality) compared with those not living with OSA. The study is a collaboration between Imperial College Health Partners; Imperial College Healthcare NHS Trust, London, UK; and Eli Lilly and Company (Lilly). The study is sponsored by Lilly, the manufacturer of obesity and diabetes medications, including tirzepatide.

OSA is characterised by recurrent upper airway obstruction during sleep and is associated with reduced quality of sleep and life and increased cardiovascular risk. The prevalence of obesity and overweight among people with OSA is between 40-70%, and people living with obesity are more likely to experience more severe OSA than those without the condition. In previous studies, weight loss has been shown to reduce OSA severity and, in some cases, may lead to remission or improved cardiometabolic risk. Despite guideline-directed therapies (e.g., continuous positive airway pressure [CPAP] machines used during sleep), OSA remains both underdiagnosed and undertreated, with important implications for morbidity, mortality, and healthcare resource use (HCRU). Real-world evidence on cardiovascular outcomes and whole system costs associated with OSA outside of sleep clinics is limited.

In this new study, the primary objective was to assess the increased risk of the combined endpoint of CVEs or death among adults (≥18 years) with a diagnosis of OSA compared to adults without OSA. Secondary objectives were to assess risk of key comorbidities (e.g., diabetes, osteoarthritis) and compare HCRU (primary care visits, out-/in-patient admissions) using de‑identified linked electronic health records from persons resident in North-West London (NWL), United Kingdom.

The study used electronic health records from 2.9 million residents. Adults with OSA were matched to up to 5 comparable people based on demographics, deprivation, smoking status, obesity status, comorbidity count, prior CVEs, and being alive at the index date (first OSA diagnosis of the OSA participant in each matched group). The authors then used statistical modelling to work out the odds of those with OSA experiencing any CVEs or death from any cause compared to those without OSA. Participants were followed for up to 4 years from index until endpoint, March 2025 or loss to follow-up/de-registration. HCRU and costs were based on national unit costs and compared using paired statistical methods.

In the analysis, 20,300 people diagnosed with OSA were matched with 97,412 comparators; 57.2% (11,613) of those participants with OSA were living with obesity vs 56.7% (55,264) of the matched participants without OSA. The authors found the risk of CVEs or all-cause mortality among people with OSA was 71% higher than in the matched controls without OSA.

Within four years after the index date, 26.3% (5,342) of those with OSA experienced CVEs or all-cause mortality compared to 17.5% (17,079) of matched controls. Among those who did not already have these other conditions at index, people with OSA also had higher proportions of developing obesity (5.6% vs 4.0%), diabetes (6.8% vs 4.6%), osteoarthritis (4.2% vs 3.0%), anxiety (5.2% vs 3.2%), and depression (4.7% vs 3.0%). Median HCRU was greater among people with OSA: primary care visits (21 vs 14 per person-year [ppy]), outpatient attendances (4 vs 1 ppy), inpatient days (1 vs 0 ppy), vs matched controls without OSA.

In adults, obstructive sleep apnea is linked to higher risk of cardiovascular events or all-cause mortality, especially among those with obesity, even after adjusting for confounders. These findings underscore the need for effective obesity management and highlight the importance of early screening and timely diagnosis. To our knowledge, this is the largest matched case-control study of obstructive sleep apnea outside the U.S. to date."

Heather Fitzke, Co-author of Imperial College Health Partners, London, UK