Over the past year, weight loss drugs have captured the public’s imagination but also raised existential questions about the future of bariatric surgery.
For obesity, surgery has long been — and continues to be — the most effective treatment, reducing patients’ risk of sleep apnea, diabetes, cancer, cardiovascular disease, and death. However, the gap between weight loss drugs and bariatric surgery is starting to narrow after Wegovy cut the risk of major heart complications by 20% in Novo Nordisk’s SELECT trial.
“Personally, I would have taken a 5% reduction,” said Angela Fitch, president of the Obesity Medicine Association, emphasizing that these results symbolize a paradigm shift in obesity medicine. With even more effective weight-loss drugs already emerging and other clinical trial evidence on the horizon, the hope is that, with medication, “we would see similar sorts of outcomes that we see with surgery,” said Fitch.
Historically, medical doctors and surgeons have engaged in fierce turf wars over patients, for everything from acid reflux to heart disease. Obesity, however, is unique in that it’s long been seen as a lifestyle condition, with only 1% of eligible patients receiving drugs or bariatric surgery. So, the recent surge of interest in weight loss drugs could help reframe obesity as a disease and, at least in the short term, increase the number of patients seeking surgical treatment, according to experts interviewed by STAT.
But the long-term outlook of bariatric surgery is murkier, caught between competing visions of harmonious medical-surgical integration and potential obsolescence under the relentless pace of biotech innovation.
A rising tide lifts all boats
Marina Kurian, president of the American Society for Metabolic and Bariatric Surgery, argued that surgical treatments are here to stay. “The SELECT trial showed a 20% reduction, which is great,” said Kurian. But bariatric surgery blows weight loss drugs out of the water, reducing major heart complications by 40%-50%, on top of various other benefits to “every organ system in the body,” she continued. “All these drugs are getting close, but they’re not close.”
However, Kurian and other bariatric surgeons largely framed surgery’s continued role in terms of the various issues with obesity drugs.
“There’s three reasons why you might choose to not be on medications,” said Dan Azagury, chief of minimally invasive and bariatric surgery at Stanford. “One, you don’t want to be on it for life; two, there’s a cost equation; three, there’s some side effects.” While he acknowledged that the price could eventually come down, for now, drugs like Ozempic and Wegovy cost most people a prohibitive $900-$1,350 per month, especially as insurance companies crack down on prescriptions and Medicare is banned from coverage.
Bariatric surgery, on the other hand, is better covered by insurance and a one-time deal for patients. “Surgery has a real advantage that medicine will never have, and that is a legacy effect,” said Michael Albert, an obesity medicine physician and chief medical officer of telehealth practice Accomplish Health. “Instead of having to take a pill and worry about if your insurance company is going to cover you the next month, you have surgery — in theory, it’s one and done.”
Certainly, bariatric surgery has its downsides as well, namely a fifth of patients gaining back 15% of body weight within five years and the various side effects like bleeding, infections, diarrhea, and stomach leaking. However, the primary reason that surgery hasn’t taken off, despite its advantages, might be something more fundamental: It’s an invasive operation for a seemingly cosmetic issue. So, as the excitement over weight loss drugs pushes the medicalization of obesity, Albert believed “that’s going to have a sort of rising tides effect with surgery as well.”
At Stanford’s Lifestyle and Weight Management Clinic, Azagury described how it currently sees around 2,000 patients a year, offering patients both medical management and surgery. With the current 1% utilization rates and obesity rates expected to reach nearly half of American adults by 2030, there’s nowhere to go but up, Azagury suggested, if the public starts seeing obesity as a disease. “The 99% of patients that we weren’t able to treat will come out of the woodwork,” he said. “Even if 90% of them choose to do medical weight loss but 5% choose to do surgery, that’s still going to be fivefold the number of surgeries.”
These two treatments are also complementary, not mutually exclusive, according to Jenny Choi, a bariatric surgeon at Albert Einstein College of Medicine in New York. “We see probably about 300 to 400 new patients a month. I would say probably 20% to 25% of patients are on medication,” said Choi. “Some patients are considering surgery because they did lose some weight with the medication, but they stalled.”
So, bariatric surgery could help patients who had limited success with medications — or vice versa. “A lot of surgeons are now offering the medications as an adjunct to their operations,” said Choi, because some patients continue to have severe obesity — either because they started at a high baseline BMI, regained weight after surgery, or didn’t respond well to surgery. Indeed, in a recent study of patients with low weight loss after surgery, those who received drug treatment as well lost an additional 8% of body weight. “I actually like the medications being around because I feel like I can offer patients more than just surgery,” said Choi.
An existential threat
While bariatric surgery volumes have been increasing from 158,000 people in 2011 to 263,000 in 2021, its continued ascendance is far from certain. Last month, Intuitive Surgical reported that the growth of bariatric surgery was slowing down as demand for obesity treatments skyrocketed. “Numbers are down a little bit,” admitted Kurian, the president of the bariatric surgery society, with several other surgeons interviewed by STAT concurring based on their own case volumes.
The hype over weight loss drugs — to bariatric surgery’s detriment — is likely to intensify with the development of more effective medications, such as Eli Lilly’s latest experimental drug, which led to 24% weight loss in a mid-stage trial. While bariatric surgery has long been well-funded because of high procedural reimbursement rates, the balance of power is now shifting toward pharmaceutical companies, according to Zaher Toumi, a bariatric surgeon at Spire Washington Hospital in England.
“Over the last few years, they’ve infiltrated everything,” said Toumi, with these companies involved in medical education, specialty training, and governmental lobbying. Combined with the near nonstop coverage of weight loss drugs in news outlets and social media, “little by little, in people’s mind, they are thinking that obesity now is the kind of problem treatable by medications.” With this greater awareness, Toumi agreed that bariatric surgery volumes would likely increase — but only in the short term.
“I expect the numbers to start going down after five years,” Toumi said, as pharmaceutical companies keep pushing the narrative of obesity as a medical disease but not necessarily a surgical one. Beyond the fact that medical doctors outnumber surgeons 18 to 1 in the United States, performing a two-hour operation isn’t as scalable as prescribing a drug, according to Eric Sheu, a bariatric surgeon at Brigham and Women’s Hospital. “It would just not be feasible at all to have surgery for everyone.”
A shift in surgical volumes could also have ripple effects, reducing the number of residents interested in bariatric surgery — “you want to be trained at something that is reasonably durable,” said Toumi — as well as research investments from medical device makers and the authority of the specialty’s professional organizations. “It will be almost impossible to get medications which are more effective than bariatric surgery,” said Toumi, but that evidence gap might not even matter against these kinds of headwinds.
There’s precedent for the eventual obsolescence of surgery, according to Choi. Anti-reflux surgery used to be the go-to treatment for stomach ulcers and heartburn, but with the advent of proton pump inhibitor medications in the late 1980s, gastroesophageal reflux disease quickly became a medical problem, better managed in the clinic than the operating room. “I think overall our volume may take a dip,” Choi said about bariatric surgery. “Am I going to be as busy as I was before? Maybe not.”
Charting the future of bariatric surgery
But there’s another historical case study for bariatric surgery’s future. When coronary stents were on the rise in the ’90s and early 2000s, “everyone was like ‘cardiac surgery is dead,’” said Kurian. After all, who would want open heart surgery when your cardiologist can do a quick, outpatient procedure to open up the clogged arteries? “What happened, unfortunately, is that a lot of people got stented, but some of them probably should have had surgery,” Kurian continued. So, cardiac surgeons didn’t go extinct; they just shifted toward caring for the more complex cases, including all the patients in whom stenting failed.
All the experts interviewed by STAT said that, for similar reasons, bariatric surgery will always be necessary for patients who are sicker, don’t respond to medications, or can’t tolerate the side effects. “I just had a patient today who I was like, ‘You need to lose another 200 pounds, and you’ve already lost 180 pounds with medical therapy,’” said Albert. “There will be opportunities for surgery; that is not going away.”
Ultimately, the future of obesity medicine might parallel that of cancer, where chemotherapy can be given before surgery to reduce tumor size and after surgery to kill residual cancer cells, said Sheu. Neither medication nor bariatric surgery will be the “magic bullet” to the obesity problem, and each of their strengths may be necessary to patch up the other’s weaknesses.
“None of these things are cures; surgery is not a cure, medicine’s not a cure,” Sheu said. “These are all just treatment options in a toolbox, and they’re going to have to be combined.”
