Efficacy in DIabetes treatment: Surgery Or coNventional: the EDISON-trial.

The prevalence of type 2 diabetes (DM2) in the Netherlands has increased dramatically in recent years and is expected to rise to 1.3 million persons in 2025. Most DM2 patients are overweight and 30-50% have obesity (body mass index > 30 kg/m2). Current therapies for diabetes increase bodyweight even further, making it very difficult to achieve the target Hba1c level of 7% or less. Patients with DM2 have a higher risk for cardiovascular disease. The complications of DM2 seriously decrease the quality of life and the life expectancy of DM2 patients, but also have large socioeconomic consequences. Weight loss is the hallmark of therapy but unfortunately current diet, exercise or drug interventions give only modest weight reduction that is not lasting.

The only intervention with proven long-term efficacy with respect to weight loss is bariatric surgery. Furthermore, bariatric surgery appears to improve DM2 in obese DM2 patients. Therefore, the number of bariatric surgeries in obese DM2 patients is increasing. However, the scientific evidence for this operation procedure is scarce and largely emanates from a meta-analysis mostly containing retrospective analyses of databases. Furthermore, the cost-effectiveness of RYGB versus conventional treatment of DM2 patients with a BMI > 35 kg/m2 has not been established. From both the patient as well as a socioeconomic perspective this procedure might be of great importance.

In this trial we investigate if RYGB is more (cost-)effective in the long-term than conventional therapy in DM2 patients with a BMI > 35 kg/m2 not adequately regulated by dual oral therapy.

The prevalence of type 2 diabetes (DM2) in the Netherlands has increased dramatically in recent years and is expected to rise to 1.3 million persons in 2025. Most DM2 patients are overweight and 30-50% have obesity (body mass index > 30 kg/m2). Current therapies for glucoregulation, with the exception of metformin and glucagon-like peptide-1 (GLP-1) analogues, increase bodyweight even further. The ensuing aggravation of insulin resistance makes it very difficult to achieve the target Hba1c level of 7% or less. Above this value the risk of chronic micro-and macrovascular complications rise dramatically. In fact, patients with DM2 have a 2-4 times increased risk for cardiovascular disease.These complications seriously decrease the quality of life and the life expectancy of DM2 patients, but also has large socioeconomic consequences. In 2005 health care costs associated with DM2 in the Netherlands amounted 814 million euro and indirect costs are unknown. Weight loss is the hallmark of therapy but unfortunately current diet, exercise or drug interventions give only modest weight reduction that is not lasting.
The only intervention with proven long-term efficacy with respect to substantial (10 kilograms or more) weight loss is bariatric surgery. Furthermore, bariatric surgery appears to improve DM2 in obese DM2 patients. Therefore, the number of bariatric surgeries in obese DM2 patients is increasing. However, there is currently only 1 prospective randomized controlled trial specifically addressing the efficacy of gastric banding versus conventional therapy in obese DM2 patients. This study showed a large benefit of gastric banding as compared to conventional therapy and was cost-effective at the short and long-term. Current practise in the Netherlands is to do a laparoscopic Roux-en-Y Gastric bypass (RYGB) procedure in obese patients with DM2, not gastric banding. The scientific evidence for this operation procedure is scarce and largely emanates from a meta-analysis mostly containing retrospective analyses of databases. In this meta-analysis the bypass was nevertheless more effective in both reducing bodyweight (-41% vs. 65.7% of the excess weight) and HbA1c (47.9% vs. 83.7% improvement of glucoregulation). Furthermore, the cost-effectiveness of RYGB versus conventional treatment of DM2 patients with a BMI > 35 kg/m2 has not been established. From both the patient as well as a socioeconomic perspective this procedure might be of great importance.



Hypothesis:

We hypothesize that RYGB is more cost-effective in the long-term than conventional therapy in DM2 patients with a BMI > 35 kg/m2 not adequately regulated by dual oral therapy who according to the Dutch Guidelines of General practitioners (standaarden van Nederlands Huisarts Genootschap) should commence insulin therapy.

0, 3, 6, 12, 24 and 36 months.

1. Roux-en-Y Gastric bypass (RYGB);

2. Conventional treatment arm: standard of care according to the Dutch Guidelines of General practitioners (NHG standard).