Q: Some of my patients with diabetes ask me about bariatric surgery. What aspects of bariatric surgery should be discussed with my patients?

Bariatric surgery can be an effective therapy for weight loss in those who are obese. The American Diabetes Association (2015) reviewed the current available studies and recommendations regarding bariatric surgery and diabetes. For those with diabetes, an additional positive effect of bariatric surgery can be an improvement in blood sugar control. Seventy-two percent of patients achieve complete normalization of blood sugar 2 years following surgery. This compares to 16% of patients treated medically with lifestyle changes and medications. Characteristics that predict success include younger age, shorter duration of Type 2 diabetes, lower A1c, higher serum insulin levels, and nonuse of insulin.

There are several types of bariatric surgery to understand (1) gastric bypass surgery, (2) laparoscopic gastric binding, and (3) sleeve gastrectomy. Gastric bypass surgery is a permanent change that shrinks the stomach and shortens the path that food takes as it travels through the small intestine. The number of calories absorbed is then limited. Laparoscopic gastric binding (lap-banding) consists of a belt wrapped around the stomach so the patient will feel full with less food. The banding can be adjusted or reversed. In sleeve gastrectomy, 80% of the stomach is removed. Sleeve gastrectomy has become the most popular weight loss surgery in the United States, accounting for 42.1% of the 179,000 procedures in the last year ("Remission rates," 2014).

Disadvantages of the procedures include cost and risk. Although the 30-day mortality rates have decreased to 0.28%, outcomes vary based on the procedure, experience of the surgeon, and the center. Safety improvements are primarily due to improvement in laparoscopic techniques. There may also be concerns with vitamin and mineral deficiencies and osteoporosis. Severe hypoglycemia from insulin hypersecretion is a rare complication.

The American Diabetes Association (2015) recommends consideration for bariatric surgery for adults with BMI >35 kg/m2 and Type 2 diabetes, particularly, patients who have not been able to control their diabetes or associated conditions with lifestyle and pharmacological therapy. Currently there is not enough evidence to recommend surgery in patients with BMI <35 kg/m2.

All approaches to bariatric surgery should include a comprehensive weight-management program with lifelong lifestyle support. Regular diabetes screenings and assessment of blood glucose should continue, even when glucose levels have normalized.

We do not yet have a full understanding of the long-term benefits and risks of bariatric surgery, particularly in those who are not severely obese. Patients who are interested in learning more about bariatric surgery should discuss their concerns with their primary care provider and experts in bariatric surgery to understand their individual potential appropriateness for the procedure.

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