Association Between Obstructive Sleep Apnea and Cardiovascular Events in Acute Coronary Syndrome Patients With or Without Revascularization - A Prospective Cohort Study.

Background: The effects of obstructive sleep apnea (OSA) on the prognosis of acute coronary syndrome (ACS) without revascularization remain unclear, so the aim of the present study was to elucidate the association of OSA with subsequent cardiovascular events in ACS patients with and without revascularization.

Methods and results: We prospectively recruited hospitalized ACS patients undergoing sleep monitoring between June 2015 and January 2020. OSA was defined as an apnea-hypopnea index ≥15 events/h. The primary endpoint was a major adverse cardiovascular and cerebrovascular event (MACCE), including cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularization, or hospitalization for unstable angina or heart failure. Among 1,927 patients, 52.6% had OSA and 69.4% underwent revascularization. During a 2.9-year follow-up (1.5-3.6 years), the risk of MACCE was similar in patients with or without revascularization. OSA was an independent predictor of MACCE in the non-revascularization group (22.6% vs. 14.6%; hazard ratio (HR) 1.861; 95% confidence interval (CI) 1.239-2.796; P=0.003) but not in revascularization group (22.3% vs. 19.3%; HR 1.135; 95% CI 0.882-1.460; P=0.324). The incremental risk in the non-revascularization group was attributable to more hospitalizations for unstable angina (14.2% vs. 8.6%; HR 1.896; 95% CI 1.124-3.199; P=0.016).

Conclusions: For patients with ACS, OSA was independently associated with higher risk of recurrent cardiovascular events among patients without revascularization but not among patients undergoing revascularization. The benefits of suitable OSA treatment for patients without revascularization need further investigation.