Obstructive sleep apnea and cardiovascular events in acute coronary syndrome: a meta-analysis

Obstructive sleep apnea (OSA) in patients with the acute coronary syndrome (ACS) were at high risk for cardiovascular events, but the results are currently inconclusive. We aimed to conduct a systematic review to determine the incidence of cardiovascular events among ACS patients with OSA by a meta-analysis of observational studies.

PubMed, Embase, and Cochrane Library were searched for studies related to the association between OSA and the risk of cardiovascular events in patients with ACS. Risk of bias in observational studies was assessed according to the Risk Of Bias In the Non-randomized Studies-Of Interventions tool.We performed a meta-analysis using a random-effects model to calculate estimates of pooled hazard ratios (HR) with 95% confidence intervals (CI), and heterogeneity was assessed using the statistics.

A total of 12 studies evaluating ACS patients with OSA were included in the meta-analysis. OSA was related to the increased risk of MACE (HR = 2.2; 95% CI, 1.274-3.805, I2  = 76.1%). The effect of OSA on MACCE (HR = 1.921; 95% CI, 1.45-2.546; I2  = 19.1%) and readmission for unstable angina (HR = 3.137, 95% CI, 1.06-9.283; I2  = 52.4%) were statistically significant in the pooled analysis. All of the outcomes in the included studies had a serious risk of bias and the Grading of Recommendation, Assessment, Development, and Evaluation evidence level of all the evaluation results were very low.

OSA was associated with a significant increase in the risk of cardiovascular events for patients with ACS. Additional randomized controlled trial studies are required to confirm the results and to prove the treatment of OSA can change the prognosis.