Bariatric Surgery: An Effective Treatment for Type 2 Diabetes

Who Should Consider Bariatric Surgery?

In 2016, the 2nd Diabetes Surgery Summit issued a treatment algorithm for metabolic surgery for type 2 diabetes treatment. Bariatric surgery is recommended in patients with BMI ≥35 kg/m2 whose hyperglycemia is not adequately controlled by optimal medical and lifestyle intervention. The algorithm also suggests that surgery should be considered in patients with BMI 30 to 34.9 kg/m2 who have inadequately controlled hyperglycemia.6

Even if a patient with type 2 diabetes meets the recommended BMI thresholds, bariatric surgery may not necessarily be the best treatment. “The biggest fear for patients and healthcare providers is the potential for surgical complications,” Ali Aminian, MD, Associate Professor of Surgery from the Bariatric & Metabolic Institute at the Cleveland Clinic in Ohio, said in an interview with Endocrinology Advisor. “Patients need to be screened for factors that may increase the risk of psychological complications, such as the increased risk of suicide after surgery.” In addition, patients who have conditions that place them at a higher operative risk, such as a myocardial infarction within the last 12 months, may not be good candidates for bariatric surgery.

For those who are surgical candidates, bariatric surgery is generally considered to be safe. “Several studies have shown that the safety of bariatric surgery is similar to that of commonly performed laparoscopic procedures, such as cholecystectomy or appendectomy,” Dr Aminian said. The Cleveland Clinic has developed an evidence-based Bariatric Surgery Decision-Making Calculator app for the iPhone7 to help endocrinologists determine the patient’s individualized metabolic surgery score, which recommends the appropriate procedure for the patient.8 The app also includes a Sleeve Gastrectomy Risk Calculator to provide an individualized risk assessment for patients considering sleeve gastrectomy.9

Bariatric Surgery: An Underused Treatment

Despite the benefits and overall safety of bariatric surgery as a treatment for type 2 diabetes, surgery is still significantly underused for this indication. “Some statistics show that only 1% or less of the people who qualify for bariatric surgery by BMI criteria actually get it,” Dr Halperin said. In addition, most insurance plans cover bariatric surgery only for those with BMI ≥35 kg/m2 if they have type 2 diabetes, even though surgery may benefit patients with diabetes and a lower BMI.

Dr Chen suggested that BMI alone should not be used to decide for or against surgery, and that other patient factors should be considered. “BMI is a screening tool that does not take into consideration other markers of metabolic abnormalities or factors such as ethnicity, body composition, age, etc. It is inappropriate for a BMI value to be the barrier to an operative therapy,” Dr Chen said.

According to Dr Halperin, there is not yet consensus about whether bariatric surgery, which prevents hyperglycemia and possibly long-term complications over time, should be performed as a preventive measure. “Surgery is still often thought of a rescue therapy for people who are failing all other therapies. It may make sense to consider surgery earlier as a preventive treatment, instead of waiting until chronic hyperglycemia and diabetes complications [have developed].”

Patient and clinician perceptions of bariatric surgery may contribute to the low rates of surgery as a treatment for type 2 diabetes. Some patients may have personal reasons for not wanting to undergo surgery, such as having a relative or spouse who had a bad experience with surgery, Dr Halperin said.

“Unfortunately, commonly held misperceptions of bariatric surgery continue to be a barrier to the perceived risk of surgery,” Dr Chen said. Some physicians view bariatric surgery as a risky treatment for type 2 diabetes, even though it is commonly performed laparoscopically and is associated with low morbidity and mortality. “Clinicians need to know that improvements in technology have allowed surgeons to offer bariatric surgery as a minimally invasive procedure with a strikingly safe operative profile.”


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