How Do We Know Endoscopic Sleeve Gastroplasty (ESG) Really Works?

Endoscopic sleeve gastroplasty, otherwise known as ESG, is the endobariatric, non-surgical alternative to weight loss surgery for many patients who aren’t interested in or eligible for bariatric surgery. Offering comparable outcomes to those seen with the surgical sleeve gastrectomy, ESG is completely non-surgical, and the entire procedure takes less than an hour. Patients go home shortly afterward and recover within days.

But, how do we know it works? Well, until now, we had plenty of anecdotal and observational data to demonstrate that patients lose a significant amount of weight after ESG. In fact, at True You Weight Loss, patients lose an average of 66% of their excess weight after 12 months. But, until recently, there was not a true, randomized trial to demonstrate the efficacy of ESG.

That’s why the True You Weight Loss team is so thrilled to share the results of the recent MERIT trial, which were announced at the International Federation for the Surgery of Obesity & Metabolic Disorders (IFSO) conference held on October 22, 2021. 

What is the MERIT Trial?

MERIT stands for the Multicenter ESG Randomized Interventional Trial. It represents a significant study for the field of endobariatrics, and for the ESG procedure.

While more than 20,000 ESG procedures have been performed worldwide since 2013, a randomized, controlled study of its effectiveness has never been conducted. MERIT was conducted across nine centers in the U.S. and enrolled a total of 208 patients. The study took two years to conduct.

‘Observational Studies’ vs. ‘Randomized, Controlled Trials’ and Why it Matters

Until now, all published ESG studies, including those from True You Weight Loss, were purely observational. That means patients come to a facility to have their procedure, and their weight loss results are recorded over time, then reported in a medical journal. These are still valuable studies, and show what kind of results patients can achieve. But to “prove” whether a treatment works, you really need to compare it to a “control” group. Meaning, a group that follows the same diet and lifestyle program as our ESG patients follow, but without having the procedure. That way, we can isolate the effect of the actual procedure itself. This is what a “controlled” study means. It’s similar to the way new medications are tested against a placebo group.

The next important element is that patients must be randomized to receive either the treatment, in this case ESG, or control (diet and lifestyle modification). Randomization helps to eliminate differences in the two groups that may affect the results. So, both groups should be similar in terms of their baseline characteristics, and any other factors that might affect how much weight they lose.

What Defines ‘Success’ for a Weight Loss Procedure?

For endoscopic sleeve gastroplasty, the major gastrointestinal and bariatric surgery societies established pre-determined metrics for what defines a successful procedure. Specifically for ESG, this includes two metrics related to overall weight loss and complication rates:

1. The treatment must produce a greater than 25% reduction in excess weight. That means if a patient is 100 pounds overweight, they should lose a minimum of 25 pounds with this procedure.
2. The procedure must have a less than 5% risk of serious complication, also known as an adverse event.

The MERIT Trial Undoubtedly Demonstrates Success of the ESG Procedure

Among the patients who received the ESG procedure, the average excess weight loss with ESG one full year after the procedure was 49%. That means patients who had 100 pounds of excess weight to lose dropped an average of 49 pounds. That is almost double the 25% cutoff for success.

The control group, who went through the same diet and exercise program without the procedure, lost only 4% of their excess weight. In the scenario of a patient who is 100 pounds overweight, that translates to a 4-pound weight loss. That’s not surprising, considering that diet and exercise by itself isn’t very effective. In conclusion, the ESG procedure produced a 45% greater reduction in excess weight.

As for adverse events, there were only three in the study, which was a 2% rate (well below the 5% threshold). Complications included one infection (abscess), one bleeding complication, and one instance of malnutrition.

Of equal importance is the sustainability of the weight loss. In the MERIT trial, patients were followed for a total of two years and maintained their weight loss for the duration of the trial. This is important evidence that proves ESG is a durable, lasting procedure.

ESG Success Rates at True You Weight Loss

At True You Weight Loss, we are proud that our patients’ results exceed even the impressive results demonstrated by the MERIT trial. In fact, on average, our patients lose 66% of their excess weight at 12 months. So, that same patient would lose 66 pounds in just one year.

As for complication rates, True You Weight Loss has had just three complications out of 1,100 ESG procedures as of this posting (November 2021). This puts our complication rate at 0.0027, falling very far below the 5% threshold set forth by our expert medical associations.

Why are our success rates so much higher than what was demonstrated in the MERIT trial? A few reasons, we believe.

1. No financial motivation. The first is that patients in the MERIT trial received their procedures free of charge. This clearly means patients have a little less skin in the game without having to make a significant financial sacrifice to pay for the procedure. We’ve heard many of our patients say they simply can’t afford for the procedure not to work—and that’s a powerful incentive for many.
2. Varying levels of physician expertise. Because the MERIT trial was spread across multiple centers, the procedures were performed by physicians with varying levels of experience/expertise. We know that ESG is a complex procedure that requires technical precision, and the truth is that practice makes perfect. True You Weight Loss and Dr. Christopher McGowan have performed more ESG procedures than any center or physician in the country.
3. COVID-19. The MERIT trial occurred right in the middle of COVID-19. As we’ve seen across the country, the emotional stress of the pandemic has led to alarming rates of weight gain and mental health problems that could have significantly impacted the results. While it’s speculation, we suspect the weight loss numbers could have been even higher if it were conducted in a non-pandemic time.
4. Differing program designs. Once again, the MERIT trial patients were spread across multiple centers that offered varying levels of support. At True You Weight Loss, we offer a fully comprehensive approach that includes 24/7 physician access, unlimited medical follow-up, and long-term one-on-one dietitian support.

In conclusion, regardless of these factors, we know that individual results will vary with any procedure and also between different programs. The great news is that this study shows without question that ESG works remarkably well. Even though all published studies up until now have shown very compelling evidence that it works, this is the highest quality study available that validates the success of ESG.

So, as we tell all of our patients—trust the process, ESG works. For patients researching ESG and relying on individual anecdotes or success stories (or failures for that matter), we can now definitely say there is a high-quality study that demonstrates the efficacy of ESG.

Congratulations and thank you to the MERIT study investigators for contributing this very important work to the field.