The Weight Loss Drug Revolution: GLP-1 RA drugs inspire new excitement for metabolic bariatric surgeons

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Glucagon-like peptide-1 receptor agonist (GLP-1 RA) drugs are emerging as a medical breakthrough in the treatment of obesity.

Some of the people most excited for them are doctors who counsel patients on metabolic bariatric surgical treatments, and the surgeons who perform those procedures.

Proponents say metabolic bariatric surgery to reduce the size of the stomach remains a valid treatment that is vastly underutilized, even misunderstood, in contemporary American medicine and health care. The new medications are not about to put them out of business, they said.

“People ask that question: Is bariatric surgery going to become obsolete? We also get asked the question: Does lifestyle change become obsolete? Do we not need to worry about diets anymore?” said Kristina Henderson Lewis, M.D., M.P.H., S.M., and associate professor of epidemiology and prevention at Wake Forest University School of Medicine.

“I think the answer to both of those is no,” Lewis said. “If anything, it makes me more excited about the outcomes that we can expect to achieve with lifestyle interventions and bariatric surgery.”

The beginning of the end?

Once the U.S. Food and Drug Administration approved the GLP-1 RA drugs for obesity management, in 2022 and 2023, there was a noticeable change in U.S. health care. Comparing the second half of 2022 with the second half of 2023, GLP-1 RA drug prescriptions shot up 132.6%. The number of patients undergoing metabolic bariatric surgery dropped 25.6%, according to “Metabolic Bariatric Surgery in the Era of GLP-1 Receptor Agonists for Obesity Management,” published in JAMA Network Open.

Is that the beginning of the end of bariatric surgery? Or the beginning of a new era of therapy?

“I think the way to think about this is from a different direction, and from the patient’s perspective, that this is almost the golden age of treatment for obesity,” said study corresponding author Thomas C. Tsai, M.D., M.P.H., a metabolic bariatric surgeon in the Department of Surgery at Brigham and Women’s Hospital in Massachusetts. “Really, it’s about how we take all the different treatment options we have and use that multidisciplinary approach to meet the overall health goals of patients.”

The time has come for obesity specialist physicians to borrow concepts from oncologists and cancer treatments, Tsai said. GLP-1RA drugs can be neoadjuvant or adjuvant treatments combined with a form of surgery that remains a gold standard treatment with the highest degree of total body weight loss, and with the most data showing long-term effectiveness.

“Really, the thinking is moved from thinking of, what is the best treatment at any given time? To thinking about, what is the best treatment course for a patient over the life cycle of what effectively is a chronic disease?” Tsai said.

That study had another telling finding, he said. Even with the shift from surgery to pharmacologic management, fewer than 6% of patients with obesity in the commercially insured population actually were treated with best-in-class medications or best-in-class surgical procedures. Only about 1% of patients who met indications for it were undergoing the procedures at a given year, Tsai said.

While those percentages are small, there is a large number of Americans dealing with obesity and overweight. The drugs are effective, but the surgeries can help people lose up to 35% of their body weight, said Caroline Apovian, M.D., FACP, FTOS, DABOM, co-director of the center for weight management and wellness at Brigham and Women’s Hospital and a professor of medicine at Harvard Medical School.

“How many people are we talking about in the United States?” she said. “Well, BMI over 40 has grown four-fold since 1960. This is about maybe seven to 10 million Amercians. Yes, those people can be helped by our new medications, but a good proportion of those people can be helped even more by bariatric surgery.”

A step forward in obesity treatment

In October 2022, NatureMedicine published “Two-year effects of semaglutide in adults with overweight or obesity: the STEP 5 trial.” The study found “substantial, sustained weight loss,” approximately 15% of body weight, for adults with obesity or with overweight and at least one weight-related comorbidity. It was part of a steady stream of reports about the new miracle drugs melting away body mass.

The same month, there was another medical development, with perhaps less attention. The American Society for Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) published their new “Guidelines on Indications for Metabolic and Bariatric Surgery – 2022.”

They replaced a consensus statement developed by the National Institutes of Health in 1991. The new guidelines were long overdue, said ASMBS President Ann Rogers, M.D., FACS, FASMBS, DABS-FPMBS, director of the surgical weight loss program at Penn State University. She credited ASMBS past president Shanu N. Kothari, M.D., for pressing the specialty for new standards of care.

“It just says something about the stigma of obesity, because we have new treatments for all sorts of things like breast cancer and colon cancer and – you name a disease, and we have something much newer than 1991,” Rogers said.

Then, the surgeries were open. The first laparoscopic metabolic bariatric surgery was done later in the 1990s. Now they are minimally invasive, and moving toward robot-assisted, with safety rates on par with or better than operations such as gall bladder removal, hernia repair or knee replacement, Rogers and Tsai said.

Some insurance companies have embraced the new standards, some have not, Rogers said. “But for patients, I think it’s opened the door for a lot of people to realize that they have this disease,” she said.

What do the insurance companies say?

Rogers, who has performed thousands of metabolic bariatric surgeries, described current trends in the patient experience with the procedure and with insurance.

Worldwide, metabolic bariatric surgery patients tend to be approximately 80% women. Most commercial insurance plans will cover bariatric surgery, Rogers said, as long as patients spend a certain amount of time or make a minimum number of physician visits in a preparation program. There is nutritional education, and insurers may or may not pay for visits with a dietitian. Some will require cardiology or pulmonary evaluations, a sleep study, or other tests. Some insurers mandate patients not gain weight during the program – not even one pound, she said.

“I mean, we jump through all sorts of hoops so that patients can get authorization for the surgery,” Rogers said. “There’s just a bunch of nonsense, really, that is not based in science.”

Patients have encountered insurance company “headwinds” in covering the new GLP-1 RA drugs. The same resistance has existed for years about paying for metabolic bariatric surgery, Tsai said.

“There really needs to be a societal conversation about, how do we increase access for life-saving medications like GLP-1s and life-saving treatments like metabolic and bariatric surgery for patients, so they can really benefit from the significant amount of medical innovation that’s happened over the last several decades,” he said.

The patient experience

Once the programs start, bariatric surgical patients become some of the best-informed surgical patients that doctors will meet, Rogers said. They get to know about nutrition, the surgical procedure itself, and potential complications. Many of them have friends or relatives who also had the surgery, so the potential patients ask them questions about their experiences, she said.

Worldwide, the programs tend to have a dropout rate of approximately 50%, Rogers said. But for the other half, eventually it is time to pick a date and the type of procedure. ASMBS estimated in 2019, almost 60% of the surgeries were sleeve gastrectomies, approximately 18% were gastric bypass, and there are other variations.

“By far the most common question is, what should I do? And I like that – thank you for not coming in with a preformed opinion,” Rogers said.

But there are expectations. Many patients will talk a good game about wanting to improve their diabetes or another health condition.

“They may not state that overtly, but everybody comes in expecting to lose a lot of weight, and then if everything else gets better, so much the better,” Rogers said.

While it’s impossible to predict exact effects, research suggests that will happen, and it’s possible to talk about averages. For example, men tend to lose more weight faster than women – often a point of annoyance for wives who undergo counseling and surgery together with their husbands, Rogers said.

Then begins long-term follow-up. Many patients, now invested and grateful, go on to live healthier and longer lives. They also revere their surgeons, Rogers added.

Primary care physicians not familiar with current practice may be living in the past, when the procedures were viewed as ill-advised, even dangerous, Rogers said.

“I would love to have people listen and believe that this is a very safe set of operations,” she said. “People continue to believe that bariatric surgery is rash and it should be the last possible choice. No, it’s conventional therapy.”