The association of obesity and in-hospital outcomes among patients undergoing ablation for atrial fibrillation: a propensity-score matched analysis

Abstract Background Obesity is a strong risk factor for atrial fibrillation (AF), and it can affect the prognosis of AF. However, the impact of obesity (BMI≥30 kg/m²) on postoperative complications after AF ablation has not been extensively studied. We aimed to evaluate the association of obesity with in-hospital outcomes among patients with AF who ablation procedures. Methods The study utilized the National Inpatient Sample (NIS) database 2016-2020. Patients were divided into obese and non-obese groups and matched with propensity score matching (1:1). This matching involved adjusting for baseline variables (including age, gender, primary expected payer, race, and median household income) and comorbidities (including diabetes, hypertension, hyperlipidemia, history of coronary artery bypass grafting (CABG), chronic kidney disease, hyperthyroidism, cardiomyopathy, prior stroke or transient ischemic attack, heart failure with preserved ejection fraction (HFpEF), heart failure with reduced ejection fraction (HFrEF), heart valve disease, coronary artery disease, chronic obstructive pulmonary disease (COPD), alcohol misuse, anemia, and smoking). Furthermore, a weighted analysis was conducted utilizing weights provided by the NIS, and multivariate logistic regression was used to calculate the odds ratio. Results A total of 29,440 patient with AF who underwent ablation were included. After propensity matching, (8,110 in obese and 8,110 in non-obese group) the baseline characteristics were not significantly different between the two groups. Obesity was independently associated with higher risk of pseudoaneurysm, hematoma, postoperative anemia, acute kidney injury, vasopressor need, mechanical ventilation, pulmonary embolism, and ischemic stroke in patients who underwent ablation for AF (Figure 1). In addition, obese group had significantly higher length of stay (median and IQR 2 [1-3] vs 2 [1-4]) and total charges (median and IQR: 131,248$ [95,303-197,784] vs 143,693$ [102,720-206728]) compared to non-obese group (p<0.001). However, in-hospital mortality was not significantly different between the two groups. Conclusion In patients who underwent AF ablation, obesity is associated with significantly higher risk of post-operative complications, as well as increased LOS and total hospital charges.