American College Of Surgeons - Inspiring Quality: Highest Standards, Better Outcomes

Should Patients Lose Weight Before Undergoing Bariatric Surgery?

OCTOBER 29, 2019
Clinical Congress Daily Highlights, Tuesday Early Edition


In a bit of tortuous irony for patients undergoing bariatric operations, today’s protocols encourage them to lose a little weight first. Michael Mazzei, MD, Temple University, Philadelphia, PA, presented a retrospective analysis suggesting that surgeons may want to revisit this thinking.

Dr. Mazzei and colleagues compared outcomes within 30 days of bariatric procedures, either sleeve or bypass, using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP®) database of 475,000 patients. The researchers stratified patients into three groups based on weight loss just prior to the procedure: those with no weight loss, those who lost up to 15 percent of their body weight, and those who lost more than 15 percent.

In the month following surgery, complication rates were similar for the group with no weight loss and the group with a little weight loss, suggesting there may be no benefit to the preoperation shedding. In fact, those who lost more than 15 percent of their body weight had 14 times the morbidity rate of those who didn’t lose weight.

Going into the procedure, patients without weight loss had fewer comorbidities compared with the other groups, and those with more than 15 percent of weight loss had more comorbidities. Still, based on regression analyses, the large weight loss was independently associated with increased morbidity.

Dr. Mazzei noted that more studies are needed to determine whether there are potential benefits to mild weight loss prior to bariatric procedures. And whether patients who have lost significant weight may undergo the procedure more safely after a particular window of time remains to be seen.

Additional Information:

The Scientific ForumBariatric/Foregut II – More is Not Better: The Impact of Preoperative Weight Loss on Bariatric Surgical Outcomes, was held TuesdayOctober 29 at the American College of Surgeons Clinical Congress 2019 in San Francisco (program, webcast and audio information).