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.

Association of obstructive sleep apnoea with long-term cardiovascular events in patients with acute coronary syndrome with or without hypertension: insight from the OSA-ACS project

BACKGROUND

A close relationship exists between obstructive sleep apnoea (OSA) and hypertension. However, the impact of hypertension on the prognostic significance of OSA in patients with acute coronary syndrome (ACS) remains unclear.

METHODS

This is a post hoc analysis of the OSA-ACS project, which consecutively included patients with ACS and receiving overnight sleep study from June 2015 to January 2020. OSA was defined as AHI ≥15 events/hour. The primary outcome was major adverse cardiovascular and cerebrovascular events (MACCE), including a composite of cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularisation or hospitalisation for unstable angina or heart failure.

RESULTS

A total of 1927 patients with ACS were finally enrolled in this study. The mean patient age was 56.4±10.5 years. Among them, 1247 (64.7%) patients had hypertension, and 1014 (52.6%) patients had OSA. During 2.9 (1.5, 3.6) years of follow-up, OSA was associated with an increased risk of MACCE among patients with hypertension (HR=1.35, 95% CI 1.04 to 1.75, p=0.02), but not in patients without hypertension (HR=1.15, 95% CI 0.79 to 1.68, p=0.47). The interaction between OSA and hypertension for MACCE was not statistically significant (interaction p=0.29). For patients with pre-existing hypertension, OSA was associated with an increased risk of MACCE only among those with grade 3 hypertension (HR 1.54, 95% CI 1.12 to 2.13, p=0.008), but not those with grade 1 or 2 hypertension.

CONCLUSIONS

OSA was associated with an increased risk of MACCE following ACS in patients with hypertension, especially in patients with pre-existing severe hypertension. These findings highlight the importance of identifying OSA in ACS patients with hypertension.

TRIAL REGISTRATION NUMBER

NCT03362385.

Results of a 1-Year Follow-Up Sleep Apnea Screening and Referral Initiative During Routine Yearly Examination of Environmental Inspection Workers

BACKGROUND

There are strong links between obstructive sleep apnea (OSA), chronic disease, mental health, job performance, and motor vehicle accidents. Corporate wellness clinics and health monitoring programs present ideal settings to educate and screen employees for OSA.

METHODS

In January 2020, the Stop-Bang Sleep Apnea Questionnaire was added to the yearly health monitoring program of 571 State of Texas air, water, and hazardous waste workers as part of routine care. Medium- and high-risk (HR) scoring employees were counseled to seek follow-up care from a primary-care provider (PCP). The January 2021 exams provided an opportunity to determine the success of counseling efforts.

FINDINGS

Of the 479 returning employees in 2021, 24 (49%) of HR and 17 (21.8%) of intermediate risk (IR) had discussed OSA with a PCP. Seven (14.3%) HR and 1 (<1%) IR employee underwent a sleep study and 4 (8.2%) were prescribed continuous positive airway pressure (CPAP).

CONCLUSIONS/APPLICATION TO PRACTICE

Screening for OSA at the workplace was inexpensive and, when diagnosed and treated, can mitigate associated chronic disease, improve worker productivity, and reduce associated accidents and injuries. The described OSA screening delivered value to the employer and employees. The screening was performed at a very low cost, involved little time on the part of the nurse practitioner and employees, brought signs and symptoms of OSA to the consciousness level of 571 employees, encouraged at-risk participants to discuss OSA with a PCP and led to 4 (8.2%) being prescribed CPAP.