Effects of continuous positive airway pressure on cardiac events and metabolic components in patients with moderate to severe obstructive sleep apnea and coronary artery disease: a meta-analysis

Study Objectives: This meta-analysis aimed to systematically assess the effects of continuous positive airway pressure (CPAP) in secondary prevention of major cardiovascular events (MACEs) in patients with moderate-to-severe obstructive sleep apnea and coronary artery disease. Methods: PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov were searched for observational studies and randomized controlled trials that compared CPAP with usual care in patients with moderate-to-severe obstructive sleep apnea with coronary artery disease. The primary outcomes were MACEs, all-cause death, acute coronary syndrome, rehospitalization for heart failure, repeat revascularization, and arrhythmia. Results: A total of 11 studies (5 randomized controlled trials and 6 observational studies) with 5,410 patients reported outcomes of MACEs. Treatment with CPAP was associated with a modest risk reduction in MACEs (risk ratio [RR] 0.87, 95% confidence interval [CI] 0.78 to 0.98; P =.02). Similarly, CPAP significantly reduced the risk of all-cause and cardiovascular death by 23% (RR 0.77, 95% CI 0.60 to 0.99; P =.04; I-2 = 0%). Subgroup analysis revealed that CPAP adherence time >= 4 hours/night had a greater benefit on MACEs by 42% (RR 0.58, 95% CI 0.42 to 0.79; P <.001; I-2 = 0%) and repeat revascularization by 44% (RR 0.56, 95% CI 0.34 to 0.92; P =.02; I-2 = 0%). Also, CPAP had a positive effect on systolic and diastolic blood pressure. Conclusions: CPAP therapy might prevent subsequent MACEs and all-cause death among patients with moderate to severe obstructive sleep apnea and concomitant coronary artery disease. CPAP use exceeding 4 hours/night may add more benefits on MACEs, repeat revascularization, and blood pressure.