The Effect and Predictive Score of Gastric Bypass and Sleeve Gastrectomy on Type 2 Diabetes Mellitus Patients with BMI < 30 kg/m2

Abstract

Background: Metabolic surgery is a novel therapy for mild obesity (BMI 30–35 Kg/m2) in type 2 diabetes mellitus (T2DM) patients. The ABCD score, which comprise age, BMI, C-peptide level, and duration of T2DM (years), was reported as useful in predicting the success of T2DM treatment using metabolic surgery. This study examines gastric bypass and sleeve gastrectomy as a salvage treatment for non-obese (BMI < 30 kg/m2) T2DM patients and evaluates the role of ABCD scores. Methods: From January 2007 to July 2013, 512 (71.2 %) of 711 T2DM patients enrolled in a metabolic surgical program had at least 1-year follow-up were recruited. Clinical data and outcomes of 80 (15.6 %) patients with BMI < 30 Kg/m2 were compared with those of the other 432 (84.4 %) patients with BMI ≥ 30 Kg/m2. Complete remission was defined as HbA1c ≤ 6 %, and partial remission was defined as HbA1c < 6.5 %. A binary logistic regression was used to identify predictors of T2DM remission. Results: Mean age of the 80 non-obese T2DM patients was 47.7 ± 9.1 years, and mean HbA1c and disease duration were 9.1 ± 1.8 % and 6.5 ± 5.1 years, respectively. Mean total body weight loss was 17.1 ± 7.4 % at 1 year, and mean BMI decreased from 26.9 ± 2.2 to 22.7 ± 2.5 kg/m2 at 1 year. Complete remission of T2DM was achieved in 25.0 % of patients, and partial remission was achieved in 23.8 %. The complete remission rate was significantly lower than the 49.5 % found in patients with BMI 30–35 and 79.0 % of patients with BMI > 35 Kg/m2. In univariate analysis, non-obese patients who had T2DM remission after surgery were heavier and had a wider waist, higher C-peptide levels, shorter disease duration, more weight loss, and higher ABCD score than those without remission. The ABCD score remained the only independent predictor of success after multivariate logistical regression analyses (P = 0.003). Conclusions: Metabolic surgery may be useful in achieving glycemic control of selected non-obese T2DM patients. The ABCD score is a simple multidimensional grading system that can predict the success of T2DM treatment.