Risk of Acute Pain in Obese Patients Undergoing Atrial Fibrillation Ablation

Background: Previous studies have indicated that obesity can lead to an increased pain sensitivity. However, the risk of acute pain in obese patients undergoing atrial fibrillation (AF) ablation remains unclear. Methods: This was a case-control study. Clinical data of patients with AF who underwent percutaneous ablation at Fuwai Hospital between January and May 2019 were retrospectively collected. Numeric pain rating scale (NPRS) and Body mass index (BMI) were used to assess severity of intra-procedural pain and pre-procedural obesity, respectively. An intra-procedural NPRS score of 4 or higher indicated the presence of acute pain, and a pre-procedural BMI of 28 or greater was considered indicative of obesity. Multivariable logistic regression analysis was performed to explore the risk of intra-procedural acute pain in obese patients. Results: A total of 333 eligible patients were divided into two groups based on presence of intra-procedural acute pain (case group: n=102 [30.6%] and control group: n=231 [69.4%]). Compared with control group, patients with intra-procedural acute pain showed higher percentage of obesity (40 [17.4%] vs 28 [27.5%]) and conscious sedation (96 [41.6%] vs 89 [87.3%]), lower percentage of diabetes history (38 [16.5%] vs 10 [9.8%]), and longer duration of procedure (median, 90 vs 110 min). The occurrence rates of acute pain during AF ablation were 41.2% for obese patients and 27.9% for non-obese patients. Obesity was independently associated with an increased risk of intra-procedural acute pain (adjusted odds ratio [OR], 2.29; 95% CI, 1.18-4.43, P = 0.014). Sub-group analysis indicated a stronger risk of intra-procedural acute pain in obese patients under conscious sedation (adjusted OR, 2.48; 95% CI, 1.13-5.42, P = 0.023). Conclusion: Under conscious sedation, obesity is an independent risk factor for intra-procedural acute pain in adult patients undergoing AF ablation.