Comparative analysis of sleeve gastrectomy with transit bipartition versus single anastomosis sleeve ileal bypass in morbidly obese patients with type 2 diabetes: a retrospective cohort study

Abstract

Objective – to compare the effectiveness of sleeve gastrectomy (SG) + transit bipartition (TB) and the novel metabolic procedure, sleeve gastrectomy with single anastomosis sleeve ileal bypass (SASI), in the treatment of morbidly obese patients with type 2 diabetes mellitus (T2DM).

Materials and methods. A retrospective cohort study was conducted among morbidly obese patients with T2DM who underwent bariatric surgical procedures, specifically SG+TB and SASI, between September 2013 and December 2024 at the study hospital. Exclusion criteria included a history of previous bariatric surgery, upper laparotomy, severe comorbidities (ASA III – IV), and psychological instability. A total of 33 patients who underwent metabolic surgery for T2DM were divided into two groups: Group I underwent SG+TB, and Group II underwent the SASI operation. The mean age of patients was 42.6 years (range: 26 to 64 years), with a mean preoperative weight of 107.5 kg (range: 92.0 – 189.5 kg), a mean preoperative body mass index of 43.2 kg/m² (range: 36.7 – 65.0 kg/m²), and a mean excess weight of 50.8 kg (range: 28 – 106 kg). The average duration of metabolic disease before surgery was 7.5 years (range: 3 – 21 years). The mean preoperative glycaemia was 11.8 mmol/L (range: 6.5 to 23 mmol/L), and the mean glycated hemoglobin (HbA1c) was 7.6% (range: 6.5 – 13.2%). The primary outcomes were the percentage of excess weight loss (%EWL), resolution of diabetes, and improvement of comorbidities. The secondary outcome was postoperative nutritional status.

Results. A cohort of 33 patients had a follow-up period of 12 to 48 months. After the Santoro operation, excess weight loss (EWL) was 72% at 6 months, 88% at 1 year, 92% at 2 years, and 86% at 4 years. After the SASI operation, EWL was 76% at 6 months, 89% at 1 year, 93% at 2 years, and 82% at 4 years. Complete resolution of diabetes occurred in all patients within the first 6 months postoperatively. Mean postoperative glycemic and HbA1c levels normalized at 1 year postoperatively. Disease control was defined as achieving normal HbA1c levels (< 6%). Among insulin-dependent patients, 76% achieved disease control during the 12- to 48-month follow-up. Patients receiving oral treatment reduced HbA1c to < 6% in 100% of cases at 1 year postoperatively and in 89% of cases over the subsequent 5 years. Two years postoperatively, the mean total protein concentration was 7.7±1.7 g/dL in Group I and 7.2±1.5 g/dL in Group II (p > 0.1). The mean albumin concentration was 4.1±0.6 g/ dL in Group I and 4.0±0.8 g/dL in Group II. The mean daily bowel movement frequency was 1.6±1.8 in both groups.

Conclusions. The novel procedure – single anastomosis sleeve ileal bypass – demonstrates effectiveness as a less invasive surgical treatment for morbid obesity and T2DM. It is expedient to conduct further investigations to evaluate the efficacy of this method and to establish clear indications and contradictions for SASI.