Obesity surgery in the time of Ozempic: ‘They are not two competing treatments, but rather complementary ones’

Innovative anti-obesity drugs, which help patients lose around 15% of their body weight, have revolutionized the fight against this complex, chronic disease. These drugs, known as GLP-1 receptor agonists, mimic hormones that naturally induce feelings of satiety. They act in the intestine, sending signals to the brain to make us feel full. Their success has been so profound that it is reshaping the foundation of obesity care, prompting a reevaluation of well-established therapeutic strategies, including obesity (bariatric) surgery. Research published in JAMA Network Open documents that, between 2022 and 2023, while the number of prescriptions for these new drugs in the United States increased by 123%, the number of patients undergoing bariatric surgery dropped by 25%.

Experts agree that in a disease as complex as obesity, no tool is superfluous — whether it be medication or surgery. However, the emergence of these new drugs has led to a review of how different strategies should fit into the management of this chronic condition and how to determine the precise limits and timing for each therapeutic option. “They are not two competing treatments, but rather complementary ones,” says José Balibrea, head of Endocrine-Metabolic and Bariatric Surgery at the Germans Trias i Pujol Hospital in Badalona, Spain.

Bariatric surgery includes all surgical techniques that alter the gastrointestinal anatomy to reduce food intake and absorption. It is recommended for the most severe cases of obesity — patients with a body mass index (BMI) above 40, or above 35 if there are associated health conditions. The JAMA Network Open study acknowledges that, for now, bariatric surgery remains “the most effective and long-lasting treatment for obesity.” However, the rise of new anti-obesity drugs and the growing trend toward medication over surgery presents a scenario full of uncertainties. It remains unclear whether this trend will continue or what the long-term effects of this potential shift in healthcare practices will be.

Andreea Ciudin, head of the Comprehensive Obesity Treatment Unit at Vall d’Hebron Hospital in Barcelona and board member of the Spanish Society for the Study of Obesity, acknowledges that GLP-1 agonists are a revolutionary strategy. “For the first time, we have treatments based on the pathophysiology of obesity,” she explains.

“In a person without obesity, when they eat, the intestine synthesizes a peptide, whose function, among others, is to signal to the brain that they have eaten and are full. In obesity there is an imbalance in appetite regulation and in how the metabolism works. One of the causes is that the brain does not receive this satiety signal properly, either because the intestine doesn’t produce the peptide correctly or because the signal doesn’t reach the brain effectively.”

The new drugs, marketed under brands such as Ozempic, mimic the function of this peptide, sending the correct satiety signals to the brain. These drugs have become one of the most promising tools in the fight against obesity, but all the experts consulted agree that their emergence does not signal, at least in the short to medium term, the end of bariatric surgery. In fact, none of the available treatments — whether surgical or pharmacological — are curative. Obesity remains a chronic condition, and the approach to its management must continue to be multidisciplinary, warns Albert Goday, head of the Endocrinology section at Hospital del Mar.

“The scenario is not that these drugs have arrived and will take over the entire market, making surgery obsolete,” he explains. “This message is absolutely wrong. Having different options for such a serious and heterogeneous chronic disease is extremely positive. But the 400 people waiting for surgery at our hospital will not be removed from the waiting list just because two highly effective drugs are available.”

The reality is more complex. Antonio Fernández, 36, and his partner, Sara Gómez, 34, understand this all too well. Both underwent surgery five years ago. At the time, Fernández weighed 155 kilos, and Gómez weighed 118. They struggled with everyday tasks, like tying their shoes. “With that much weight, you feel useless. You can’t move, you can’t work, you can’t live a normal life. You don’t feel capable of anything,” says Fernández.

He was the first to enter the Severe Obesity Unit at Hospital del Mar and begin to “change his chip.” He emphasizes that it’s not just an operation: “The biggest process is recognizing that you have a disease and allowing yourself to be helped and advised by professionals to learn how to eat and live.”

After Fernández, his wife followed suit. Then, several other family members with severe obesity also sought help. Goday notes that the couple became role models for those around them, demonstrating a “positive contagion capacity” that helped improve the health of other family members. “What we’re most proud of is that we’ve managed to empower them, and now they understand that they live with a disease and need to manage it to prevent it from spiraling out of control. They are not to blame for this disease,” the doctor stresses.

The most effective treatment

When it comes to the hopes surrounding GLP-1 agonists, Goday is clear: “They are welcome, but they are not the only pillar of treatment.”

Obesity is far more complex than it might appear. Given the various types and degrees of the disease, access to medication, and the health outcomes, the situation is nuanced. Anna Casajoana, a bariatric surgery specialist at Hospital del Mar, explains that the amount of weight that can be lost through medication is lower than what can be achieved through surgery.

“Right now, the drugs we have — as much as they are improving — are indicated for cases of overweight patients. They are not a treatment for established obesity,” says Casajoana. “Could it be a bridge for patients who are unsure about surgery and want to try pharmacological treatment first? It’s an option, but once you stop the medication, the weight returns because no other intervention, like education on healthy habits, has been made. In the future, we all hope that treatment for obesity will not rely solely on surgery, because we know surgery is not a magic solution. But today, it is the most effective treatment we have.”

The available GLP-1 agonists are still in their first generation. While they show promising results and research continues to improve and optimize their potential, for now, health outcomes are more favorable with surgery. A study published in Nature Medicine concluded, for instance, that surgical interventions were linked to a greater reduction in the incidence of congestive heart failure.

“Surgery leads to significantly greater weight loss, improves cardiovascular problems, and addresses fatty liver disease. Diabetes control is comparable, but surgery significantly increases longevity and reduces the risk of cancer,” says Balibrea, who is also a spokesperson for the Spanish Association of Surgeons.

On the other hand, neither GLP-1 agonists nor bariatric surgery are free from the risk of relapse. Weight gain can occur after both therapeutic strategies. Goday again stresses the importance of a comprehensive approach: “You have to recognize that you have a chronic disease. Medication, without the broader context of empowering the individual, is not going to work. And surgery isn’t a definitive treatment either. This disease is trying to win by any means, and your environment, food prices, and advertising are all helping it to win the game. While there are more tools available now, we still face many enemies in winning this battle.”

All the experts consulted agree that, in the most severe cases, surgery will still be necessary. “Bariatric surgery will be reserved for patients who, after receiving treatment, do not respond, who do not achieve the desired results, or who cannot afford the medications,” Balibrea summarizes.

Synergies between drugs and surgery

In the evolving landscape shaped by new therapeutic strategies, there is also room for synergies. Balibrea believes that these drugs can help reduce the number of second surgeries caused by weight gain. “After bariatric surgery, you can add one of these drugs to maintain weight loss or to prevent weight gain if it’s detected early.” The drugs could also be used to aid weight loss before surgery.

Ciudin agrees: “We need to rewrite the narrative. [These two therapeutic strategies] cannot be mutually exclusive — they can work hand in hand. Bariatric surgery is not going to disappear; it still plays a role in treating severe obesity, just as it did when it first emerged. But there is still much to be done to determine where these new drugs fit in and if they have a potential comparable to bariatric surgery.”

Sign up for our weekly newsletter to get more English-language news coverage from EL PAÍS USA Edition