New Bariatric Surgery Guidelines Reflect Rapidly Evolving Field

Miriam E. Tucker

March 28, 2013

Updated clinical practice guidelines for bariatric surgery reflect its therapeutic potential for patients with lower body weight who have other cardiometabolic risk factors. They also affirm that sleeve gastrectomy is an equally acceptable option.

The guidelines, developed by a 12-member panel, were issued jointly by the American Association of Clinical Endocrinologists, The Obesity Society, and the American Society for Metabolic & Bariatric Surgery. They were published online March 25 in the journals of those 3 organizations: Endocrine Practice, Obesity, and Surgery for Obesity and Related Diseases.

They address perioperative nutritional, metabolic, and nonsurgical support for bariatric surgery patients, and reflect new data, explained panel cochair Adrienne Youdim, MD, who is medical director of the Center for Weight Loss at Cedars Sinai Medical Center in Los Angeles, California.

"Since the publication of the 2008 guidelines, there has been an abundance of new research in the area of bariatric and metabolic surgery. These guidelines have been revised to keep pace with the available evidence in this field," Dr. Youdim told Medscape Medical News.

In this update, there is more high-grade evidence than in the previous version; 40% of the recommendations in the updated guidelines stem from strong level 1 and 2 evidence, compared with just 16% in 2008, Dr. Youdim said.

Francesco Rubino, MD, a metabolic surgeon at the Catholic University of Rome in Italy, told Medscape Medical News that this "shows that there is a common [view] among physicians and surgeons in terms of considering this therapy as an important treatment option for patients with obesity and diabetes."

The Guidelines

The updated guidelines contain 74 recommendations, whereas the 2008 version contained 164.

As in the previous version, the panel advises that bariatric surgery be offered to patients with a body mass index (BMI) of 40 kg/m² or greater without coexisting medical problems and to those with a BMI of 35 kg/m² or greater with comorbidities such as type 2 diabetes, hypertension, hyperlipidemia, or obstructive sleep apnea.

The update adds that patients with diabetes or metabolic syndrome and a BMI of 30.0 to 34.9 kg/m² can "be offered a bariatric procedure, although current evidence is limited."

Dr. Rubino called this a "courageous" move, noting that the consideration of bariatric surgery for people with a BMI below the 35 kg/m² cutoff was previously "taboo," although the International Diabetes Federation made this recommendation 2 years ago. "Now we know there is no real medical evidence supporting a specific BMI cutoff. That taboo is no longer there, and the panel recognized that surgery should be considered when other options fail."

The panel advises that the choice of procedure and approach be based on the individualized goals of therapy, available surgical expertise, patient preference, and risk stratification.

Laparoscopic adjustable gastric banding, laparoscopic sleeve gastrectomy, laparoscopic Roux-en-Y gastric bypass, laparoscopic biliopancreatic diversion, and biliopancreatic diversion with duodenal switch can be used for weight loss and/or metabolic control. In general, laparoscopic procedures are preferred over open procedures for safety reasons.

Other detailed evidence-based recommendations in the updated guidelines address perioperative management, medical clearance, early postoperative care, optimal follow-up care, and criteria for postoperative hospital admission.

Changing Philosophy

According to Dr. Youdim, the most important updates are the recognition that sleeve gastrectomy is an effective surgery, comparable to other bariatric procedures in terms of weight loss and comorbidity resolution, and the fact that the remission of diabetes is durable in a significant proportion of bariatric surgery patients, and is likely a function of the hormonal or incretin effect of surgery in addition to the weight loss.

The panel notes that the recognition of this metabolic effect has prompted a recent shift in terminology — from bariatric surgery to metabolic surgery. Dr. Rubino believes this name change will be important in shaping perception about the therapeutic potential.

"As long as we call it 'weight loss' or 'bariatric' surgery, we indicate that the primary intent of it is to make people lose weight. We will continue to promote the very wrong idea that we're trying to achieve weight loss with a very risky and costly intervention [instead of exercise].... It's not true, but that's the perception of obesity. I think calling things by the proper name is a step in the right direction," Dr. Rubino explained.

Dr. Youdim noted that a clearer understanding of the mechanism of diabetes remission in bariatric surgery patients is needed, as are clinical data demonstrating the long-term benefits of surgery in lower-BMI populations.

In addition, more information is needed to preoperatively identify patients who will experience complications from surgery, "including but not limited to recurrence of diabetes and weight regain," she told Medscape Medical News.

The updated guidelines have been endorsed by the European Association for the Study of Obesity, the International Association for the Study of Obesity, the International Society for the Perioperative Care of the Obese Patient, the Society American Gastrointestinal Endoscopic Surgeons, the American College of Surgery, and International Federation for the Surgery of Obesity and Metabolic Disorders.

Dr. Youdim has disclosed no relevant financial relationships. Dr. Rubino reports receiving research grants from Covidien and honoraria from Ethicon, and serving as a consultant and scientific advisory board member for NGM Biopharmaceuticals.

Endocr Pract. Published online March 25, 2013. Abstract