Long-term changes in disordered eating in patients with obesity after bariatric surgery

Background: There may be differences in disordered eating symptoms between healthy individuals and patients with obesity, and bariatric surgerymay influence postoperative disordered eating behaviors in patients with obesity. This study aims to explore the differences in network analysis structures of factors associated with disordered eating symptoms in healthy individuals versus patients with obesity, and further analyze changes in disordered eating symptoms in patients with obesity following BS. Methods: Between September 2020 and June 2023 in Shanghai, China, participants were stratified into two groups based on body mass index (BMI) criteria: a healthy control group (HC, n=61; BMI 18.5-24 kg/m²) and an obese group (OB, n=78; BMI ≥30 kg/m²). All participants completed the Eating Disorders Inventory-2. The OB group subsequently underwent laparoscopic sleeve gastrectomy at participating institutions, with monthly postoperative EDI-2 assessments conducted. Network analysis was employed to examine differences in factors associated with disordered eating symptoms between healthy individuals and patients with obesity, while linear mixed model combined with time series hierarchical cluster analysis were systematically applied to evaluate the interventional effects of BS on disordered eating. Result: EDI-2 total score was significantly higher in obese patients than in the healthy population ( p < 0.05). Network analysis showed that the core symptom nodes for disordered eating symptoms were Social Insecurity in the healthy population and Interoceptive Awareness, Ineffectiveness and Bulimia in the obese patients. The analysis of the postoperative follow-up data showed that the EDI-2 total score of obese patients decreased significantly from the 3rd month after surgery and remained stable ( p < 0.05). The factors related to disordered eating symptoms in obese patients showed three modes of improvement after surgery: Bulimia factor improved significantly in the early postoperative period (2nd month); Impulse regulation, Maturity Fears, Driver for Thinness and Body Dissatisfaction factors showed progressive improvement (3-24 months); Interpersonal Distrust, Social Insecurity, Perfectionism, Interoceptive Awareness, Ineffectiveness and Asceticism factors showed no significant change or even worsened. Conclusion: This study elucidates the network characteristics of disordered eating symptoms in obese patients prior to bariatric surgery, providing an evidence-based foundation for preoperative psychological interventions. Furthermore, by investigating postoperative trajectories of disordered eating symptoms and related factors, our findings highlight the critical need for future research to: (1) monitor long-term (>2 years) evolution of disordered eating symptoms, and (2) systematically evaluate psychological factor dynamics during postoperative follow-up. These investigations should inform the development of tailored psychological therapies to optimize surgical outcomes.