Metabolic Surgery for Diabetes Treatment: Sleeve Gastrectomy or Gastric Bypass?

Background: Bariatric surgery has gained reputation for its metabolic effect and is increasingly being performed to treat type 2 diabetes mellitus (T2DM). However, there is still a gray area regarding the choice of surgical procedure according to patient characteristics due to inadequate evidences, so far. We aim to compare the efficacy of two most commonly performed bariatric/metabolic surgeries, sleeve gastrectomy (SG) and gastric bypass (GB) with regard to remission of T2DM after surgery.

Methods: Outcomes of 579 (349 female and 230 male) patients who had undergone SG (109) or GB (470) for the treatment of T2DM with 1-year follow-up were assessed. The remission of T2DM after SG or GB surgery was evaluated in matched groups using the ABCD scoring system. The ABCD score is composed of the age, BMI, C-peptide levels and duration of T2DM (years).

Results: The weight loss of the SG patient at 1 year after surgery was similar to the GB patients [26.3 (1.1) vs. 32.6 (1.2) %; p = 0.258]. The mean BMI decreased from 35.7 (7.2) to 28.3 (3.7) Kg/m in SG patients at 1 year after surgery and decreased from 36.9 (7.2) to 26.7 (4.5) Kg/m in the GB patients. The mean HbA1c decreased from 8.8 to 6.1 % of the SG group and from 8.6 to 5.9 % of the GB group. Sixty-one (56.0 %) patients of the SG group and 300 (63.8 %) of the GB group achieved complete remission of T2DM (HbA1c < 6.0 %) at 1 year after surgery without statistical difference. However, GB exhibited significantly better glycemic control than the SG surgery in groups stratified by different ABCD score. At 5 year after surgery, GB had a better remission of T2DM than SG (53.1 vs. 35.3 %; p = 0.055).

Conclusions: In conclusion, although both SG and GB are effective metabolic surgery, GB carries a higher power on T2DM remission than SG. ABCD score is useful in T2DM patient classification and selection for different procedures.