Duodenal Switch vs. Single-Anastomosis Duodenal Switch (SADI-S) for the Treatment of Grade IV Obesity: 5-Year Outcomes of a Multicenter Prospective Cohort Comparative Study

Purpose The aims were to compare the 5-year outcomes of duodenal switch (DS) and single-anastomosis duodenal switch (SADI-S) in terms of weight loss; remission of comorbidities; nutritional status short- and long-term complications; postoperative mortality; and need for revisional surgery. Materials and Methods Multicenter prospective observational study of all consecutive patients undergoing DS or SADI-S in three high-volume hospitals. Results A total of 87 patients were included in the study, 43 submitted to DS and 44 to SADI-S, with similar basal characteristics, nutritional parameters, and BMI (52.9 kg/m 2 DS vs. 52.5 kg/m 2 SADI-S). Operative time was 152 min (± 32.6) in DS vs. 116 min (± 21.9) in SADI-S ( p = 0.043). Short-term complications were similar for DS and SADI-S, both overall (11.8% vs. 11.6%), and ranged as Clavien-Dindo > II (4.5% vs. 4.7%), with no mortality. At 5 years, DS and SADI-S results were as follows: BMI 30.6 vs. 33.3 kg/m 2 ( p = 0.023); %EWL 80.5% vs. 68.6% ( p = 0.006); and %TWL 42.1 vs. 36.0 ( p = 0.006). Comorbidity remission rates for DS and SADI-S were as follows: for diabetes, 92.8% vs. 85.7% (n.s.); for hypertension, 95.2% vs. 85.1% (n.s.); for sleep apnea, 75% vs. 73.3% (n.s.); and for dyslipidemia, 76.4% vs. 73.3% (n.s.). DS showed lower levels of vitamin B 12 , iron, vitamin E, and zinc than SADI-S ( p = < 0.005). In the long term, there were 4 surgical reinterventions (due to 1 internal hernia in the DS group and 1 internal hernia and 2 biliary refluxes in the SADI-S group) with no cases of persistent diarrhea or malnutrition. Conclusion Both DS and SADI-S allowed good weight control and resolution of comorbidities. DS achieved a greater weight loss compared to SADI-S, at the expense of longer operative time and lower vitamin and mineral levels. Graphical abstract