The Effects of Laparoscopic Sleeve Gastrectomy with Duodenojejunal Bypass on Japanese Patients with BMI < 35 kg/m² on Type 2 Diabetes Mellitus and the Prediction of Successful Glycemic Control

Background: Laparoscopic sleeve gastrectomy with duodenojejunal bypass (LSG-DJB) is a combination of sleeve gastrectomy and proximal intestinal bypass through duodenal exclusion. This technique has shown excellent weight loss and anti-diabetic effects in severely obese patients. In this retrospective study, we examined the clinical effects of LSG-DJB on mildly obese patients (body mass index (BMI) < 35 kg/m²) with type 2 diabetes mellitus (T2DM) and analyzed factors contributing to the successful postoperative glycemic control.

Methods: Seventy-two consecutive Japanese patients with T2DM with a BMI of < 35 kg/m² who underwent LSG-DJB in a single institution from September 2007 to March 2015 were included for the study. Weight loss, safety, and the impact on T2DM and metabolic syndrome were examined at 1 year after surgery when weight loss reaches an expected plateau. In addition, pre- and postoperative factors between those who achieved diabetes remission (remitters) and non-remitters were compared.

Results: The follow-up rate at 1 year after surgery was 93%. The mean percent total weight loss (%TWL) was 31.6 ± 8.8%, and the mean glycosylated hemoglobin (HbA1c) dropped from 8.9 ± 1.5 to 6.4 ± 1.0%. There were four early- and seven late-severe complications (grade III-A or more based on the Clavien-Dindo classification), which account for the 1-year morbidity rate of 15%. There was no mortality. The complete (HbA1c of < 6% without diabetes medication) and partial (HbA1c of < 6.5% without diabetes medication) remission of T2DM was achieved in 31 and 49% of the patients, respectively. Positive impacts were also observed on hypertension and dyslipidemia. Consequently, the ratio of those who achieved the composite endpoint (HbA1c of < 7%, low-density lipoprotein cholesterol < 100 mg/dL, systolic blood pressure < 130 mmHg) significantly increased from 4.2 to 22% (p = 0.003). Duration of T2DM and preoperative use of anti-hypertensive drugs were independent predictors of diabetes remission. Patients with a higher ABCD score were also at a higher rate of success in T2DM remission.

Conclusions: LSG-DJB for T2DM patients with a BMI of < 35 kg/m² is a feasible and effective surgical method in achieving moderate weight loss and excellent improvement of glycemic control, metabolic syndrome, and cardiovascular risk although the T2DM remission rate was lower compared with severely obese individuals. Proper patient selection for candidates of the procedure is imperative to effectively predict poor responders.