Comparative Characteristics of Patients with Type 2 Diabetes Mellitus Treated by Bariatric Surgery Versus Medical Treatment: a Multicentre Analysis of 277,862 Patients from the German/Austrian DPV Database

Introduction Bariatric surgery is a well-established treatment option for serious obesity and concomitant type 2 diabetes mellitus (T2DM). In this analysis, we investigated predictors for bariatric surgery in everyday clinical practice. Materials and Methods In the DPV-registry, patients with T2DM from Germany and Austria treated by bariatric surgery were compared to non-surgery controls by descriptive statistics and regression analysis. Results Among 277,862 patients with T2DM, 0.07% underwent bariatric surgery. Surgery patients were predominantly female [61.20%], younger [median age (Q1;Q3) 54.74(47.40;61.61) vs. 70.04 (60.36;77.58) years] and had a longer diabetes duration [11.21 (7.15;17.93) vs. 8.36 (2.94;14.91) years]. They had a higher BMI [40.02 vs. 30.61 kg/m 2 , adjusted p < 0.0001] and a slightly lower HbA1c [7.25 vs. 7.56%, adjusted p < 0.05]. There was a trend using more often insulin therapy (52.79 vs.50.08%, n.s.) with no difference in insulin dose/kg × day [0.56 vs. 0.58, n.s.]. Sleeve gastrectomy was performed most frequently, followed by Roux-en-Y gastric bypass, gastric banding, gastric balloon and others. A 2-year follow-up data in 29 patients demonstrated significant reductions in BMI [45.23 to 38.00 kg/m 2 , p < 0.005] and HbA1c [7.98 to 6.98%, p < 0.005], and a trend for reduced insulin requirements [62.07 vs. 44.83%, n.s.]. Conclusion Despite favourable 2-year outcomes, bariatric surgery is still used rarely in patients with T2DM and obesity. BMI rather than metabolic control seems to represent the major selector for or against bariatric surgery in T2DM.