The evidence is compelling. Bariatric Surgery does work to enable weight loss and remission of diabetes. Much has been written on this subject and most recently a paper was published in the New England Journal of Medicine, “Bariatric Surgery versus Intensive Medical Therapy in Obese Patients with Diabetes,” by Schauer, Kashyap, Wolski et. al (senior author: Deepak Bhatt) (N Engl J Med 2012; 366:1567-1576 April 26, 2012). The authors performed a randomized, non-blinded, single-center trial (STAMPEDE- Surgical Treatment and Medications Potentially Eradicate Diabetes Efficiently) where they evaluated “the efficacy of intensive medical therapy alone versus medical therapy PLUS Roux-en-Y gastric bypass or sleeve gastrectomy (standard bariatric surgical procedures) in 250 obese patients with uncontrolled diabetes.” The mean age was 49, plus or minus 8 years (66 percent were women). Eligibility criteria required participants to be 20 to 60 years old. The average hb A1c was 9.2 percent. The primary endpoint (or goal of the study) was the proportion of patients with hb A1c levels of 6.0 or less after 12 months of treatment.
What were the results?
- 93 percent or 139 patients completed the study and participated in the 12-month follow-up
- 12 percent in the medical therapy group alone reached the primary endpoint
- 42 percent in the gastric bypass group reached the primary endpoint (p<0.002)
- 37 percent in the sleeve gastrectomy group reached the primary endpoint (p<0.008)
- Glycemic control (hb A1c) did improve in all three groups.
- Medical therapy group: 7.5 percent.
- Gastric bypass group: 6.4 percent (p<0.001).
- Sleeve-gastrectomy group: 6.6 percent (p<0.003).
- Weight loss was greater in the gastric-bypass group and sleeve gastectomy
Group (loss of 29.4 kg and 25.1 kg respectively) than in the medical therapy group (loss of 5.4 kg). (p<0.001)
- The amount of medications to lower glucose, lipid and blood pressure levels
significantly decreased after either surgical procedure; however, increased in patients receiving medical therapy alone. Insulin therapy remained high (38 percent) at 12 months in the medical therapy group and was reduced to 4 percent and 8 percent in the gastric-bypass group and the sleeve-gastrectomy group respectively.
Thus, 78 percent and 51 percent of the gastric -bypass and sleeve-gastrectomy patients, respectively required no diabetes medications after 12 months (p<0.05).
- Adverse events: additional surgical procedures were required for 4 patients
that included laparoscopic procedures for blood clot evaluation, assessment of nausea and vomiting and a cholecystectomy. There were no deaths or episodes of serious hypoglycemia among all groups.
What is the significance of this study?
According to the references in this study, observational studies of bariatric procedures have shown rates of remission of type 2 diabetes between 55 and 95 percent. A cited non-randomized prospective trial comparing bariatric surgery versus conventional medical therapy for obesity demonstrated remission of type 2 diabetes after two years and 10 years, but also showed recurrence over time. As this trial enrolled patients with more advanced type 2 diabetes with a duration of more than eight years and higher mean hb A1c (including treatment with at least three diabetes medications, as well as insulin administration, in 44 percent of patients), it is not surprising that the remission rate of type 2 diabetes was not as high as previous studies enrolling patients with less advanced type 2 diabetes.