Analysis of the trajectory of depressive symptoms and influencing factors in patients undergoing metabolic and bariatric surgery

Background and aims This study aims to investigate the factors influencing depressive symptoms both before and after metabolic and bariatric surgery (MBS) in obese patients, as well as to analyze the contributing factors to heterogeneous subgroups with distinct depression trajectories. Methods This study enrolled 184 obese patients who underwent MBS at Changzhou Second People’s Hospital between October 2023 and October 2024. Body composition and clinical laboratory data were obtained preoperatively, as well as at 1 month, 3 months, and 6 months postoperatively. The 9-item patient health questionnaire was used to assess the severity of depressive symptoms. Results Depressive scores showed a significant decrease at 1 month, 3 months, and 6 months postoperatively. Multiple linear regression indicated that anxiety consistently served as a risk factor for the development of depression in MBS patients, while higher medication adherence, vitality, role emotional, and resting potential scores acted as protective factors against depression progression. Growth mixture model analysis identified two heterogeneous subgroups in the depression trajectories of MBS patients. Binary logistic regression revealed that patients with comorbid hypertension and low health transition scores exhibited lower preoperative depression levels and were more likely to belong to the “mild depression decline group”. In contrast, patients with comorbid anxiety, low medication adherence, and high vitamin B12 levels showed higher preoperative depression levels and tended to belong to the “significant depression decline group”. Conclusions Patients with anxiety disorder are prone to developing depression after MBS. Patients with comorbid anxiety, low medication adherence, and high vitamin B12 levels exhibit higher preoperative depression severity and require particular attention. However, their postoperative depression levels decreased significantly, highlighting the importance of postoperative follow-up for effective emotional management in this subgroup.