Comparison of SADI-S Versus SG in Chinese with Diabetes and BMI < 35 kg/m2:a Retrospective Study with Medium-Term Outcomes.

Background: As a modification of the duodenal switch (DS), the single-anastomotic ileo-ileal bypass combined with sleeve gastrectomy (SADI-S) has recently gained popularity and has been successfully employed for weight loss and the remission of type 2 diabetes mellitus (T2DM). However, current studies predominantly focus on patients with severe obesity.

Objectives: In this study, we present the first comparison of single-anastomotic duodenoileal bypass combined with sleeve gastrectomy (SADI-S) and sleeve gastrectomy (SG) for the mid-term treatment of Chinese diabetic patients with a BMI < 35 kg/m2. This research provides comparative reports on the efficacy of these two surgical approaches.

Patients and methods: We included 53 diabetic patients with BMI < 35 kg/m² who underwent either SADI-S or SG and were followed for 2 years postoperatively. Demographic characteristics, weight loss, and nutritional and metabolic outcomes were analyzed at 3-month, 6-month, 1-year, and 2-year follow-up intervals. All surgeries were performed by the same surgeon at a single weight loss center in China between July 2015 and November 2022.

Results: A total of 24 patients who underwent Single Anastomosis Duodenal-Ileal Bypass with Sleeve Gastrectomy (SADI-S) and 29 patients who underwent Sleeve Gastrectomy (SG) were included in our analysis. Comparative analysis of the baseline indicators between the two groups revealed no statistically significant differences (P > 0.05).Both patient groups completed a 2-year follow-up. In terms of weight loss, the SADI-S group demonstrated superior outcomes compared to the SG group, with better results in weight, BMI, and total weight loss percentage (%TWL) at the 2-year follow-up, and these differences were statistically significant (66.9 ± 7.9 vs. 61.2 ± 6.6, p = 0.007; 23.8 ± 2.0 vs. 21.7 ± 1.6, p = 0.000; 31.1% ± 6.3% vs. 24.4% ± 6.4%, p = 0.000). Regarding diabetes remission, the SADI-S group also outperformed the SG group (p = 0.000). Specifically, 91.8% of patients in the SADI-S group achieved complete remission of T2DM, compared to 41.4% in the SG group (p = 0.000). Furthermore, the SADI-S group showed significantly better results in the remission of hyperlipidemia compared to the SG group.However, there was no significant difference in hypertension relief between the SADI-S group and the SG group. Additionally, the incidence of postoperative hypozincemia was significantly higher in the SADI-S group compared to the SG group (p = 0.038). No significant differences were observed in other postoperative nutritional outcomes between the two groups.

Conclusion: In Chinese diabetic patients with a BMI < 35 kg/m², both SADI-S and SG were effective in treating obese T2DM.However, compared with SG, primary SADI-S can achieve better weight loss and remission of obesity-related metabolic diseases.Additionally, the rates of postoperative nutritional deficiencies were found to be acceptable. Nonetheless, multicenter studies with larger sample sizes and longer follow-up periods are necessary to draw definitive conclusions.