The Effects of Glycemic Optimization Before Gastric Bypass Surgery

Investigation of the Effects of Glycaemic Optimisation Before Gastric Bypass Surgery on the Glycaemic Remission and Microvascular Complication Rates of Type 2 Diabetes Mellitus

Metabolic surgery such as gastric bypass, gastric banding or sleeve gastrectomy operations can cause rapid and uncontrolled reductions in blood glucose. There is limited information on whether:

• metabolic surgery is superior to modern medical care for glycaemic control and type 2 diabetes remission.
• metabolic surgery is safe for microvascular complications of Type 2 diabetes
• good glycaemic control pre surgery has any effects on the long term glycaemia and complications of type 2 diabetes.

This study aims to assess:

1. whether metabolic surgery is better for diabetes control compared to medical treatment.
2. whether metabolic surgery is safe for eye, nerve and kidney complications.
3. whether good sugar control before metabolic surgery improves the long term effects of sugar control and microvascular complications.

This is a prospective study involving 150 patients with type 2 diabetes mellitus (T2DM) and obesity. One hundred patients will undergo gastric bypass surgery whilst 50 will be treated with best medical care. The surgical patient group will be randomised to either immediate surgery or 3 months of medical glycaemic optimisation followed by surgery (n=50 group).

Intervention Group A: Patients will undergo gastric bypass surgery within 3 months after randomisation without any pre operative optimisation of glycaemic control.

Group B: Patients will undergo gastric bypass 3-6 months after randomisation. During this period the group will receive modern best medical care based on the American Diabetes Association (ADA)/European Association for the Study of Diabetes (EASD) guidelines. Glycaemic optimisation will be achieved with particular attention to the avoidance of hypoglycaemia.

Group C: Obese patients with T2DM (who choose not to have surgery) will be treated with best medical care based on the ADA/EASD guidelines including anti-diabetes/obesity pharmacotherapy, access to a trained dietician and exercise programme.

Inclusion Criteria:

1. Adult patients with T2DM and BMI above 35kg/m2
2. HbA1c ≥ 8.5% and/or the presence of at least one microvascular complication.

Exclusion Criteria:

• End stage retinopathy, nephropathy or neuropathy.