Remission of Obesity-Related Sleep Apnea and Its Effect on Mortality and Cardiovascular Events After Metabolic and Bariatric Surgery: A Propensity Matched Cohort Study.

BACKGROUND:While obstructive sleep apnea (OSA) is common among patients with obesity and linked to cardiovascular disease, there is a lack of studies evaluating the effects of reaching remission from OSA after metabolic and bariatric surgery (MBS). STUDY DESIGN:A registry-based nationwide study including patients operated with sleeve gastrectomy or Roux-en-Y gastric bypass from 2007 until 2019 in Sweden. Patients who reached remission of OSA were compared to those who did not reach remission, and a propensity score matched control group of patients without OSA at the time of operation. Main outcome was overall mortality, secondary outcome was major cardiovascular events (MACE). RESULTS:In total, 5892 patients with OSA and 11,552 matched patients without OSA completed a 1-year follow-up and were followed for a median of 6.8 years. Remission of OSA was seen for 4334 patients (74%). Patients in remission had a lower risk for overall mortality (cumulative incidence 6.0% v. 9.1%;p<0.001) and MACE (cumulative incidence 3.4% vs 5.8%;p<0.001) at 10-years after operation compared to those who did not reach remission. The risk was similar to that of the control group without OSA at baseline (cumulative incidence for mortality 6.0%, p=0.493, for MACE 3.7%, p=0.251). CONCLUSION:The remission rate of OSA was high after MBS. This was in turn associated with reduced risk for death and MACE compared to patients who did not achieve remission reaching a similar risk seen among patients without OSA at baseline. A diligent follow-up of patients who do not reach remission remains important.