Safe Harbour

Bringing Clarity to the Safety of a Gastric Sleeve

Well-controlled data for surgical procedures is hard to come by. This is especially true for bariatric surgery, where strong feelings come into play and thus, people aren’t willing to accept random assignments to a surgical procedure. So a new study in JAMA Surgery that gives us clarity about the safety of gastric sleeve operations is especially welcome.

This study tells us pretty clearly that gastric sleeves are a little safer than gastric bypasses. But the trade-off is that the chances are a bit higher for a follow-up operation when a person gets a gastric sleeve.

Five-Year Safety Data

This research, led by Ryan Howard, uses data from a national Medicare claims database. Researchers analyzed five-year outcomes for 95,405 patients who had bariatric surgery between 2012 and 2018. Of those, 38,402 had a bypass, while 57,003 had a gastric sleeve. The demographics were skewed: 74 percent of these patients were women, 78 percent were White. This skew is very typical of the patient population that can and does have access to bariatric surgery – unfortunately.

After five years, the incidence of mortality was 4.27 percent for sleeves and 5.67 percent for bypasses. Complications were also lower for the sleeve patients – 22 percent versus 34 percent. But 2.91 percent of sleeve patients required a follow-up surgery, compared to 1.46 percent of the bypass patients.

Similar Costs

Adding up the costs for care, it turns out that the sleeves cost less in the first year, but that advantage fades to nothing by the third year after the surgery. After five years, total costs for all healthcare in the sleeve group has added up to $86,584, versus $85,762. Statistically, these differences are insignificant.

This is remarkably similar to a recent finding from Canada by Jean-Eric Tarride et al. After four years, they found no differences in healthcare costs between sleeve and bypass surgeries.

Controlling for Inherent Bias

It’s important to note that these are observational studies and systematic biases are at work in the selection of a gastric sleeve or a bypass. So the instrumental variable analysis technique in the new study by Howard et al is especially valuable. It serves to balance unmeasured factors that would otherwise confound the comparison. In an invited commentary, Anita Courcoulas and Bestoun Ahmed call this approach a creative and valid success.

Thus, we can be confident that the safety of a gastric sleeve is a bit higher than a bypass. But that safety comes at the cost of a greater possibility for needed a second surgery.

Click here for the study by Howard et al and here for the invited commentary. For the Tarride study and a companion commentary, click here and here. For additional reporting, click here and here.

Safe Harbour, photograph © Manolo Guijarro / flickr

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October 7, 2021

2 Responses to “Bringing Clarity to the Safety of a Gastric Sleeve”

  1. October 07, 2021 at 4:58 pm, Michael said:

    Hi Ted, The options for revisional surgery after a RYGB are a lot less than after a LSG. Just because there were fewer follow-up surgeries after a RYGB doesn’t necessarily mean that there was less need for them. Perhaps after RYGB there was the same or even greater need for revisional surgery, just less surgical options available – so less operations done.

    • October 08, 2021 at 4:41 am, Ted said:

      Good point, Michael. Why? is the important question we can ask when new findings surface.