The effect of obstructive sleep apnea on readmissions and atrial fibrillation after cardiac surgery.

STUDY OBJECTIVE: To understand the effect of obstructive sleep apnea on readmission rates and post-operative atrial fibrillation in the cardiac surgical population.

DESIGN: Retrospective cohort study.

SETTING: Administrative database consisting of 2007-2014 data from California, Florida, New York, Kentucky, and Maryland from the State Inpatient Databases, Healthcare Cost and Utilization Project.

PATIENTS: A total of 506,604 patients ≥18 years old who underwent coronary artery bypass grafting surgery (CABG) and/or valve surgery were included in the study. After excluding for death during the index hospitalization and missing data, 396,657 patients remained for 30-day readmission analysis.

INTERVENTIONS: None.

MEASUREMENTS: Primary outcomes were unadjusted rates and adjusted odds of 30-day readmission. Secondary outcomes included post-operative atrial fibrillation and readmission diagnoses. Bivariate associations were assessed between OSA status, covariates and potential confounders, and outcomes. Odds ratios (OR) with 95% confidence intervals (CI) were estimated. Statistical significance was assessed at p < 0.05.

MAIN RESULTS: The overall 30-day readmission rate was 17.2%, with a rate of 19.6% vs. 17.1% in the OSA vs. non-OSA group (p < 0.001). Patients with OSA had higher odds of 30-day readmission (OR = 1.08, 95% CI 1.06-1.11) and higher odds of developing post-operative atrial fibrillation (OR = 1.04, 95% CI 1.01-1.08) compared to non-OSA patients. The most common reason for readmission was atrial fibrillation (38.6%), with OSA patients presenting with atrial fibrillation more frequently than their counterparts (41.7% vs. 38.4%, p < 0.001).

CONCLUSIONS: Patients with OSA are at increased risk of 30-day readmission and post-operative atrial fibrillation following cardiac surgery compared to those without OSA. Although the importance of OSA is increasingly recognized, it remains a significant risk factor for post-operative readmissions and morbidity. Further research is needed to optimize perioperative management of patients with OSA, but these results highlight the importance of this disease on patient outcomes and healthcare costs.