SUPPLEMENTARY DATA:

Surgical technique of Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG)

In brief, laparoscopic RYGB included the creation of a small proximal gastric pouch of about 20mL along the lesser curvature of the stomach, the division of the jejunum 40cm distal to the ligament of Treitz, an end-to-side gastrojejunostomy of about 1.5cm in diameter using a circular stapler, and a side-to-side jejunojejunostomy 150cm distal to the gastrojejunostomy. The laparoscopic SG consisted in the resection of the greater curvature from the distal antrum (5cm proximal to the pylorus) to the angle of His including the complete fundus. A laparoscopic stapler, EndoGIA (Autosuture, Norwalk, CT, USA) with a 60-mm cartridge (3.5-mm staple height, blue load), was used to divide the stomach alongside a 34 French bougie (placed against the lesser curvature of the stomach).

Table 1. Logistic regression analysis of clinical features associated with initial remission of type 2 diabetes or insulin cessation

T2D remission / Sustained
insulin cessation
OR / 95% CI / p / OR / 95% CI / p
Age
(years) / 1.003 / 0.940-1.071 / 0.919 / 1.014 / 0.947-1.085 / 0.688
BMI
(Kg/m2) / 1.134 / 0.963-1.336 / 0.131 / 1.055 / 0.936-1.188 / 0.381
Gender
(Female as reference) / 0.919 / 0.215-3.920 / 0.909 / 1.267 / 0.314-5.019 / 0.095
Baseline HbA1c
(%) / 0.901 / 0.583-1.394 / 0.641 / 0.660 / 0.437-0.998 / 0.049
T2D duration
(years) / 0.844 / 0.742-0.961 / 0.011 / 0.929 / 0.854-1.012 / 0.091
Type of insulin regimen
(non-BB as reference) / 4.429 / 1.156-16.971 / 0.030 / 4.039 / 1.373-18.494 / 0.015
Type of surgery
(SG as reference) / 1.750 / 0.427-7.170 / 0.355 / 4.413 / 0.771-25.264 / 0.095
Maximum EWL
(%) / 1.068 / 1.017-1.122 / 0.009 / --- / --- / ---
EWL at last follow-up visit
(%) / --- / --- / --- / 1.039 / 1.009-1.069 / 0.009
Length of follow-up
(years) / --- / --- / --- / 0.963 / 0.934-0.993 / 0.015

T2D: Type 2 diabetes; BMI: body mass index; HbA1c: hemoglobin A1c, BB: basal bolus insulin therapy; SG: sleeve gastrectomy; EWL: excess weight loss.

Figure 1: Weight trajectories (A), hemoglobin A1c changes (B), and Type 2 diabetes remission rates (C) throughout follow up in subjects that underwent Roux-en-Y gastric bypass (RYGB) or Sleeve Gastrectomy (SG).

** 74 (74) 74 (74) 74 (74) 74 (74) 58 (51) 54 (40) 47 (32) 35 (24) 22 (20)

A: Black bars: RYGB-group; Grey bars: SG-group. B and C: Black line: RYGB; Grey line: SG-group. * p<0.005 RYGB-group vs SG group. **: Number of patients that were eligible for follow-up (number of patients with data available at each time point).

Figure 2: Kaplan-Meier curve showing rates of Roux-en-Y gastric bypass (RYGB) and Sleeve Gastrectomy (SG) subjects who presented with initial remission of type 2 diabetes that were free of diabetes relapse.

Dotted line: RYGB. Solid line: SG

Figure 3: Kaplan-Meier curve showing rates of Roux-en-Y gastric bypass (RYGB) and Sleeve Gastrectomy (SG) subjects who initially achieved a hemoglobin A1c <7% and subsequently maintained this glycemic goal.