More Evidence: What to Expect from Bariatric Surgery

Two new studies give us more evidence on what to expect from bariatric surgery. Both of them provide data on outcomes after five years: one for patients with sleeve gastrectromy and the other for patients with gastric bypass or biliopancreatic diversion. Taken together, they serve to remove some of the uncertainty about long term outcomes.

The study of gastric bypass and biliopancreatic diversion was a randomized, controlled study comparing each of these two procedures to medical treatment of type 2 diabetes in people with a BMI of 35 or greater. They found that, even after five years and regardless of weight loss, the surgery patients had healthier cholesterol levels, lower cardiovascular risk profiles, less medication use, and better control of their diabetes.

This isn’t the first time that surgery has been found to deliver better diabetes control than medical treatment in people with obesity. However, it is the first controlled study with 5-year outcome data. And it adds to the reassurance that bariatric surgery is a pretty good option if you have obesity and diabetes.

The other study is an observational study that provides some of the best long-term data on sleeve gastrectomy yet. Not surprisingly, it shows that five years after this procedure, some patients regain weight and some experience a relapse in type 2 diabetes that the surgery had put into remission.

On average, patients had lost 77% of their excess weight after one year. Weight regain pushed that number down to 56% after five years. Complete diabetes remission rates went from 51% to 20% at the same time points. These data are consistent with other analyses that have suggested “sleeves” are not quite as effective as gastric bypass, but that they have lower complication rates.

It’s worth noting that we don’t really have definitive, randomized comparisons of sleeve and bypass procedures. So as they say, more research is needed.

Nevertheless, the evidence is building to suggest that bariatric surgery is one of the most effective options for people with severe obesity and its complications. Its low utilization looks more and more like a missed opportunity for improving the health of hundreds of thousands — or perhaps millions — of people.

Click here to read the study of bypass and biliopancreatic diversion, here for the study of sleeve gastrectomy, and here for an analysis of comparative effectiveness for bypass and sleeve procedures.

Evidence, photograph © tanakawho / flickr

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September 7, 2015