The objectives are to compare the results of the Gastric By-Pass (GBP) to that of optimized medical therapy in patients with obesity and poorly controlled type 2 diabetes in terms of mortality, weight loss, glycemic control, quality of life, cost, cost-effectiveness and cost utility of these two strategies.

Optimizing the management of type 2 diabetes (T2D) will remain a major public health concern for decades to come. T2DM has already affected 4% of the French population and generates each year over 12 billion euros of expenditure. By combining therapies, oral and/or injectable (insulin or analogues of GLP-1), the current management of T2DM provides two thirds of patients with a satisfactory metabolic control (HbA1c < 7%) and reduced incidence of cardiovascular complications. Its effect on mortality, however, remains more limited, presumably because of the persistence of other cardiovascular risk factors. A recent study has confirmed that French patients with T2DM present an overall mortality risk significantly higher than the general population. In France, this group registered a mortality of 32 deaths per 1000 persons.

Bariatric surgery is now a recognized method for the treatment of severe obesity. It allows for the permanent loss of at least 50% of initial excess weight. In obese patients, this surgery is also associated with a significant reduction in cardiovascular risk factors and particularly T2D. A recent meta-analysis of retrospective studies available suggests that surgery results in remission of T2DM in over 75% of cases. The only prospective randomized study showed that gastric restriction by placing a gastric band, provides better glycemic control than just medical treatment in obese patients with recently discovered T2DM. The gastric by-pass (GBP) which also includes an intestinal by-pass, seems to have an even higher metabolic efficiency than gastric bypass alone. In patients with T2DM, the GBP restores postprandial insulin secretion independently of weight loss. Despite the significant morbidity of the intervention, long-term results seem broadly supportive of the GBP. In a large case-control study, GBP was associated with a decrease of 90% of deaths related to diabetes. In a controlled study conducted in surgical candidates obese diabetics, the GBP decreased the overall world mortality by 75% after 6 years. Despite these very encouraging data, the GBP is now proposed to only a small proportion (< 1%) of patients likely to benefit from the procedure.

Inclusion Criteria:

• Type 2 diabetes mellitus with HbA1c > 7.5 %
• Body mass index > 35 and < 50 kg/m2
• Candidate for Gastric By-Pass
• Treatment with GLP1 (glucagon-like peptide) analogue or insulin

Exclusion Criteria:

• Contraindication to bariatric surgery
• Pregnancy
• Affiliation of health care assurance
• Psychiatric disorders