Objective: To discuss the potential contribution of "metabolic" surgery in providing optimal management of patients with type 2 diabetes mellitus (T2DM).
Methods: A literature search was performed with use of PubMed, and the clinical experience of the authors was also considered.
Results: Bariatric-or, more appropriately, metabolic-surgical procedures have been shown to provide dramatic improvement in blood glucose levels, blood pressure, and lipid control in obese patients with T2DM. In these patients, metabolic surgery involves a low risk of short-term mortality and a significant long-term survival advantage, whereas the diagnosis of diabetes is associated with significant long-term mortality. Experimental studies in animals and clinical trials suggest that gastrointestinal bypass procedures can control diabetes and associated metabolic alterations by mechanisms independent of weight loss. As a result, the use of bariatric surgery and experimental gastrointestinal manipulations to treat T2DM is increasing, even among less obese patients. Although body mass index (BMI) currently is the most important factor for identifying candidates for bariatric surgery, evidence shows that a specific cutoff BMI value cannot accurately predict successful surgical outcomes. Furthermore, BMI appears limited in defining the risk profile for patients with T2DM.
Conclusion: Current BMI-based criteria for performance of bariatric surgery are not adequate for determining eligibility for operative treatment in patients with diabetes. Large clinical trials, comparing bariatric surgery versus optimal medical care of patients with T2DM, should be given priority in order to define the role of surgery in the management of diabetes. Recognizing the need to work as a multidisciplinary team that includes endocrinologists and surgeons is an initial step in addressing the issues and opportunities that surgery offers to diabetes care and research.