Photomicrographs of Liver Structure and Steatosis

Sleeve vs Bypass: Effect on Liver Fat

Following closely on a landmark study of bariatric surgery and liver fat, today we have a new RCT comparing the effects of gastric sleeve and gastric bypass. In short, these two procedures work equally well. After one year, patients with both procedures had about a 20 percent reduction in liver fat. The other endpoint was liver fibrosis. On this measure, most patients in both groups were stable. Again, there were no big differences between the two groups.

If you think a 20 percent reduction in liver fat doesn’t sound impressive, think again. This reduction meant that after a year, all of the bypass patients had either no steatosis or only a low degree of it. For 94 percent of the sleeve patients, this was also true.

Together with the landmark study by Ali Aminian et al, this research tells us that either a gastric bypass or sleeve can be a potent tool for controlling NAFLD, which is common in persons with obesity and type 2 diabetes. Controlling NAFLD is important because it can lead to progressive scarring (fibrosis) of the liver, cancer, liver failure, and death. Serious stuff.

A Careful RCT

To compare the effects of these two surgical procedures, Kathrine Aglen Seeberg and colleagues randomly assigned patients to receive either a gastric sleeve or a bypass. These were patients with type 2 diabetes and an average BMI of 42. Mean age was 47.5 years and 65 percent of the patients were female. A total of 100 patients completed this trial.

It’s worth noting that, for most of the outcomes, the numbers for gastric bypass were slightly, but not significantly better. Because the study had only 100 subjects, the power to detect small differences was not great. But investigators will be following this cohort for five more years.

Some data suggest that bypass may be more effective in people with type 2 diabetes. But other analyses find minimal or no differences. So it will be valuable to see what the longer-term outcomes are in this cohort.

A Potent Tool

Without a doubt, bariatric surgery is a potent tool for persons with obesity and complications such as diabetes or liver disease. For diabetes, it offers the best chance of long term remissions from the disease. For liver disease – NASH – it cuts the risk of progressive harm by 88 percent.

We get it. Bariatric surgery is daunting. But if you or a person you care for has either NASH or type 2 diabetes, along with obesity, surgery might be their best chance for better health.

Click here for the new study by Seeburg et al, here, here, and here for further perspective.

Photomicrographs of Liver Structure and Steatosis, figure from a paper by by Paola Raquel B. de Oliveira et al, licensed under CC BY 4.0.

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November 30, 2021