8.11 Metabolic surgery should be recommended as an option to treat type 2 diabetes in appropriate surgical candidates with BMI 40 kg/m2 (BMI 37.5 kg/m2 in Asian Americans) and in adults with BMI 35.039.9 kg/m2 (32.537.4 kg/m2 in Asian Americans) who do not achieve durable weight loss and improvement in comorbidities (including hyperglycemia) with reasonable nonsurgical methods. A
8.12 Metabolic surgery may be considered as an option for adults with type 2 diabetes and BMI 30.034.9 kg/m2 (27.532.4 kg/m2 in Asian Americans) who do not achieve durable weight loss and improvement in comorbidities (including hyperglycemia) with reasonable nonsurgical methods. A
8.13 Metabolic surgery should be performed in high-volume centers with multidisciplinary teams that understand and are experienced in the management of diabetes and gastrointestinal surgery. C
8.14 Long-term lifestyle support and routine monitoring of micronutrient and nutritional status must be provided to patients after surgery, according to guidelines for postoperative management of metabolic surgery by national and international professional societies. C
8.15 People presenting for metabolic surgery should receive a comprehensive readiness and mental health assessment. B
8.16 People who undergo metabolic surgery should be evaluated to assess the need for ongoing mental health services to help them adjust to medical and psychosocial changes after surgery. C
Several gastrointestinal (GI) operations including partial gastrectomies and bariatric procedures (35) promote dramatic and durable weight loss and improvement of type 2 diabetes in many patients. Given the magnitude and rapidity of the effect of GI surgery on hyperglycemia and experimental evidence that rearrangements of GI anatomy similar to those in some metabolic procedures directly affect glucose homeostasis (36), GI interventions have been suggested as treatments for type 2 diabetes, and in that context they are termed metabolic surgery.
A substantial body of evidence has now been accumulated, including data from numerous randomized controlled (nonblinded) clinical trials, demonstrating that metabolic surgery achieves superior glycemic control and reduction of cardiovascular risk factors in patients with type 2 diabetes and obesity compared with various lifestyle/medical interventions (17). Improvements in micro-vascular complications of diabetes, cardiovascular disease, and cancer have been observed only in nonrandomized observational studies (4453). Cohort studies attempting to match surgical and nonsurgical subjects suggest that the procedure may reduce longer-term mortality (45).
On the basis of this mounting evidence, several organizations and government agencies have recommended expanding the indications for metabolic surgery to include patients with type 2 diabetes who do not achieve durable weight loss and improvement in comorbidities (including hyperglycemia) with reasonable nonsurgical methods at BMIs as low as 30 kg/m2 (27.5 kg/m2 for Asian Americans) (5461). Please refer to Metabolic Surgery in the Treatment Algorithm for Type 2 Diabetes: A Joint Statement by International Diabetes Organizations for a thorough review (17).
Randomized controlled trials have documented diabetes remission during postoperative follow-up ranging from 1 to 5 years in 30%63% of patients with Roux-en-Y gastric bypass (RYGB), which generally leads to greater degrees and lengths of remission compared with other bariatric surgeries (17,62). Available data suggest an erosion of diabetes remission over time (63): 35%50% or more of patients who initially achieve remission of diabetes eventually experience recurrence. However, the median disease-free period among such individuals following RYGB is 8.3 years (64,65). With or without diabetes relapse, the majority of patients who undergo surgery maintain substantial improvement of glycemic control from baseline for at least 5 (66,67) to 15 (45,46,65,6870) years.
Exceedingly few presurgical predictors of success have been identified, but younger age, shorter duration of diabetes (e.g.,
Beyond improving glycemia, metabolic surgery has been shown to confer additional health benefits in randomized controlled trials, including substantial reductions in cardiovascular disease risk factors (17), reductions in incidence of microvascular disease (74), and enhancements in quality of life (66,71,75).
Although metabolic surgery has been shown to improve the metabolic profiles of patients with type 1 diabetes and morbid obesity, establishing the role of metabolic surgery in such patients will require larger and longer studies (76).
Metabolic surgery is more expensive than nonsurgical management strategies, but retrospective analyses and modeling studies suggest that metabolic surgery may be cost-effective or even cost-saving for patients with type 2 diabetes. However, results are largely dependent on assumptions about the long-term effectiveness and safety of the procedures (77,78).