Medication following bariatric surgery for type 2 diabetes mellitus (BY-PLUS) study: rationale and design of a randomised controlled study

Introduction Bariatric surgery is an effective method of controlling glycaemia in patients with type 2 diabetes mellitus (T2DM) and obesity. Long-term studies suggest that although glycaemic control remains good, only 20%–40% of patients will maintain remission according to the American Diabetes Association criteria.Purpose This trial aims to examine the safety and efficacy of combining Roux-en-Y gastric bypass or sleeve gastrectomy with goal-directed medical therapy to improve long-term glycaemic control of T2DM.Methods and analysis This prospective, open-label multicentre randomised controlled trial (RCT) will recruit 150 patients with obesity and T2DM from tertiary care obesity centres. Patients will be randomised 1:1 to receive either bariatric surgery and standard medical care or bariatric surgery and intensive goal-directed medical therapy, titrated to specific targets for glycated haemoglobin (HbA1c), blood pressure (BP) and low-density lipoproteins (LDL) cholesterol. The primary endpoints are the proportion of patients in each arm with an HbA1c