Obstructive Sleep Apnea and Outcomes in Cardiac Surgery: A Systematic Review with Meta-Analytic Synthesis (PROSPERO...

Background: Obstructive sleep apnea (OSA) is a prevalent but frequently underdiagnosed comorbidity in patients undergoing cardiac surgery, including coronary artery bypass grafting (CABG), aortic valve replacement (AVR), and mitral valve repair or replacement (MVR). This systematic review and meta-analytic synthesis investigates the relationship between OSA and postoperative morbidity and mortality, with particular attention to the predictive utility of established screening instruments. Methods: A systematic search of the PubMed database was conducted (April 2025), identifying 724 articles published in the last ten years. Seventeen primary studies met the inclusion criteria for qualitative synthesis, and four additional studies were included in the meta-analyses. Outcomes assessed included atrial fibrillation, major adverse cardiac and cerebrovascular events (MACCE), acute kidney injury (AKI), respiratory complications, pneumonia, hospital length of stay (LOS), and mortality. Risk of bias was assessed qualitatively based on study design and reporting limitations. This review was registered in the PROSPERO database under registration number CRD420251049574. Results: Meta-analyses demonstrated significantly elevated odds of atrial fibrillation (OR = 2.44, 95% CI: 1.46-4.07), major adverse cardiac and cerebrovascular events (OR = 2.06, 95% CI: 1.61-2.63), acute kidney injury (OR = 2.24, 95% CI: 1.67-3.01), and respiratory complications (OR = 1.15, 95% CI: 1.05-1.25) among patients with OSA. Additionally, OSA was associated with a significantly prolonged hospital length of stay (standardized mean difference [SMD] = 0.62, 95% CI: 0.46-0.78) and a marginal increase in pneumonia risk (OR = 1.07, 95% CI: 1.00-1.15). Evidence regarding stroke, intensive care unit (ICU) stay, and mortality was inconsistent or underpowered. Conclusions: Across core outcomes, findings were consistent across multiple studies involving a large patient population. Obstructive sleep apnea is a clinically consequential risk factor in cardiac surgery, associated with increased perioperative complications and prolonged hospitalization. These findings support the integration of routine OSA screening into preoperative risk assessment protocols. Further prospective, multicenter trials are warranted to assess the efficacy of perioperative management strategies, including continuous positive airway pressure (CPAP) therapy, in improving surgical outcomes.