Longitudinal Cohort Study Comparing 2 Surgical Techniques in Patients With Class 3 Obesity and Type 2 Diabetes
Condition: Obesity; Type 2 Diabetes
MeSH terms: Diabetes Mellitus; Obesity; Diabetes Mellitus, Type 2
Study type: Observational

Summary: 
      Wight loss surgery provides good glycemic control in type 2 diabetes. The technique of
      "Roux-en-Y gastric bypass" is more effective than the "Adjustable Gastric Band" on weight
      loss.

      This longitudinal cohort study will compare the effectiveness of the Roux-en-Y gastric bypass
      and Adjustable Gastric Banding on glycemic control in type 2 diabetes and explore the
      responsible mechanisms.

      The evaluation will be made preoperatively and 1 year later as assessed by the decline in
      HbA1c. An evaluation will also be carried out after a weight loss of 10% to indicate whether
      the observed difference is independent of weight loss.
    

Detailed description: 
      Type 2 diabetes is a condition often associated with obesity and often difficult to control.
      In patients with severe obesity, surgical treatment allows a sustainable weight loss and
      higher than that obtained with other treatments available. In most cases, surgery also
      reduces significantly the comorbidities of obesity and diabetes in particular. Among the
      various technical options, adjustable gastric band (AGB) is the simplest and by far the most
      used in France.

      Roux-en-Y gastric bypass (RYGB) is a more complicated intervention combining gastrointestinal
      malabsorption- duodeno-jejunal and gastric reduction and allows a higher weight loss. Several
      studies also suggest that the technique has a remarkable efficiency on glycemic control,
      justifying the extension of its readings/indications. No study controlled, however, has
      compared these two techniques.

      The objective of this study is to compare the efficiency of RYGB vs AGB on glycemic control
      in type 2 diabetes. Although some studies have compared AGB and RYGB, none have compared
      their effectiveness on post prandial glucose control in patients with diabetes. It is
      generally recognized that the effectiveness of RYGB on diabetes is independent of the weight
      loss, but this has never been demonstrated.

      By demonstrating the superiority of RYGB vs AGB, and identifying the responsible mechanisms,
      the study will expand the indications of RYGB in the treatment of type 2 diabetes. Weight
      loss surgery offers a unique model for the clinical study of the pathophysiology of type 2
      diabetes.

      Main objective:

        -  To compare the effectiveness of RYGB vs AGB on glucose control in obese patients with
           type 2 diabetes.

      Secondary Objectives:

        -  demonstrate that the better outcome achieved with RYGB is independent of weight loss.

        -  Identify the mechanisms underlying the better outcome of RYGB
    

Intervention name(s): Roux-en-Y gastric bypass; Adjustable gastric band
Intervention type(s): Procedure; Procedure
Intervention description(s): Laparoscopic Roux-en-Y gastric bypass; Laparoscopic adjustable gastric band
Other intervention name(s): Gastric bypass; Gastric Banding
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Candidate for bariatric surgery (Roux-en-Y gastric bypass OR adjustable gastric band) with
        class 3 obesity (body mass index ≥ 35 kg/m2) and type 2 diabetes (ADA definition)

        OR healthy volunteers
      
Biospecimen description: 
      serum and plasma during meal test (0, 30, 60, 90, 120, 180 min)
    
Keywords: type 2 diabetes; obesity; gastric bypass; adjustable gastric banding; BMI > 35.; obesity for more than 5 years