A recent international conference called the Diabetes Surgery Summit has developed preliminary recommendations regarding metabolic surgery for the treatment of patients with type 2 diabetes and obesity.
Traditionally, bariatric surgery (commonly referred to as gastric or weight loss surgery) has been used as a weight control method for the treatment of obesity. The surgery works to lower weight by reducing the size of the stomach with a gastric band or through removing a part of the stomach. Recently however, there is compelling evidence to suggest that bariatric/metabolic surgery may be an appropriate treatment option for type 2 diabetes (T2D). Since most clinicians and patients are unaware that surgery may be a viable treatment option, a Diabetes Surgery Summit (DS-11) convened to address this issue.
The DS-11 met with leading diabetes organizations to develop global recommendations that combine medical and surgical therapies. Developing selection criteria for surgery would hopefully lead to insurance reimbursement policies for the surgical treatment of diabetes. After conducting a MEDLINE literature review spanning ten years, a questionnaire was used to measure consensus for 32 conclusions. To prevent conflict of interest, voting delegates were academics (instead of industry representatives) with nonsurgeons making up the majority of the group, followed by academic surgeons. Randomized control studies (RCT) that assessed the effectiveness of surgery vs. nonsurgical therapies for T2D as well as the effects of different types of surgery on blood sugar levels were included in the literature review. Available studies were also included to assess the cost-effectiveness of metabolic surgery.
Results show that metabolic surgery was excellent in lowering blood sugar levels as well as weight but that these benefits were most prevalent in the first 5 years. Surgery was also effective in reducing cardiovascular risk factors. Several bariatric operations caused a T2D remission but reoccurrence was likely over time. From an economic standpoint, surgery appeared to be cost effective with the cost per quality-adjusted life-year (QALY) for bariatric/metabolic surgery being $3200-$6300; well below the $50, 000/QALY deemed appropriate for coverage. Drug costs were also lower for surgery patients.
Risks of surgery included death, complications, reoperations and readmissions and varied from hospital to hospital. The most important predictor of surgery outcome was the training and skill of the surgeon. Nutritional deficiencies requiring lifelong vitamin/nutritional supplements were another disadvantage of surgery.
Based on the evidence, metabolic surgery should be recommended to treat:
- T2D in patients with Class III obesity (BMI over equal to or greater than 40 kg/m2)
- Class II obesity (BMI 35.0-39.9 kg/m2) and diabetes
- T2D and BMI 30.0-34.9 kg/ms
As a short term intervention, metabolic surgery may be used as an antidiabetes intervention for people with T2D and obesity. Additional studies are required to further assess its long term benefits.
Written By: Aurelie Hartawidjojo, BSc, BScPT