The Effect of Long-Term Immunosuppression on Patients Undergoing Sleeve-to-Gastric Bypass Conversion Surgery

Sleeve conversion to Gastric Bypass (SG-RYGB) surgery is the most common conversion surgery in the United States. However, chronic Immunosuppressive therapy (CIT) may be a relative contraindication prior to metabolic and bariatric surgery (MBS) due to the potential for a complicated postoperative course and recovery, particularly in patients undergoing complex, secondary MBS.

This study assesses the impact of CIT on both short-term and long-term outcomes following SG-RYGB surgery.

This retrospective review study compared outcomes of patients at a single academic center who underwent SG-RYGB conversion surgery from January 2012 to December 2024. Patients were divided into two groups based on perioperative CIT status: the CIT group included those with documented use of chronic systemic immunosuppressive medications for at least three months prior to surgery, while the non-CIT group had no history of such therapy. Data collected included patient demographics, Body Mass Index (BMI), underlying disease, immunosuppression regimen, and early and late complications, such as rehospitalization, reinterventions, and mortality.

One hundred twenty-six patients had SG-RYGB surgery; the average age for patients was 52.5 ± 11.5 years, 87.3% female. Of these, 23 patients (18.3%) were classified as the CIT group, having received chronic systemic immunosuppression for at least three months before surgery. In the CIT group, organ transplantations (47.8%) and rheumatoid arthritis (26.3%) were most common. Among perioperative and postoperative outcomes, the only statistically significant difference observed was a longer length of stay for CIT patients (P = 0.046), likely reflecting closer postoperative monitoring. Otherwise, short- and long-term postoperative outcomes were comparable between the CIT and non-CIT groups, with no significant differences observed in this cohort.

Except for a slightly longer hospital stay, short- and long-term outcomes appeared comparable between patients with and without CIT undergoing complex conversion surgery. However, larger studies are needed to confirm these findings and to help define the precise effect of CIT on outcomes of complex conversion surgery.