Comparing perioperative differences: Sleeve gastrectomy vs. Roux-en-Y gastric bypass

NewsGuard 100/100 Score

A recent study published in JAMA Network Open evaluates the differences in perioperative outcomes between laparoscopic sleeve gastrectomy (SG) and laparoscopic Roux-en-Y gastric bypass (RYGB).

Study: Comparison of Sleeve Gastrectomy vs Roux-en-Y Gastric Bypass: A Randomized Clinical Trial. Image Credit: Donenko Oleksii / Shutterstock.comStudy: Comparison of Sleeve Gastrectomy vs Roux-en-Y Gastric Bypass: A Randomized Clinical Trial. Image Credit: Donenko Oleksii /


The worldwide prevalence of obesity has increased substantially, with many studies indicating that this metabolic disorder is associated with significant mortality. Individuals with severe obesity may undergo metabolic and bariatric surgery, which is otherwise known as weight loss surgery, for weight management.

Although SG and RYGB are the most commonly performed surgical bariatric procedures, no studies have compared their safety and effectiveness. Until 2017, the most widely performed bariatric surgical procedure was RYGB in Sweden, until it ultimately shifted to SG.  

RYGB has been associated with providing sustained weight loss and improvements in overweight-related comorbidities; however, this procedure is associated with an increased risk of abdominal pain, small bowel obstruction, nutritional deficiencies, alcohol use disorder, and post-bariatric hypoglycemia 

European randomized clinical trials have compared SG and RYGB and revealed no significant differences in weight loss and resolution of comorbidities between the two procedures. Although diabetic patients who underwent RYGB exhibited better glucose control than those subjected to SG, these findings are based on limited-size clinical trials. 

About the study

The current randomized and large-scale clinical trial compared the effectiveness of SG and RYGB in weight loss and risk to adverse events to determine which weight reduction surgical technique is more efficient. This study is extremely important due to the sudden increase in SG procedures in Sweden and Norway.

Perioperative outcomes of SG and RYGB, based on a large Swedish and Norwegian randomized clinical trial, were presented. A previously published Bypass Equipoise Sleeve Trial (BEST) methodology was followed, which was a multicenter randomized clinical trial that assessed the five-year outcomes of SG and RYGB.

Perioperative outcomes were measured between zero and 30 days of SG and RYGB, along with 90-day mortality. The study cohort included individuals 18 and older with a body mass index (BMI) between 35 and 50.

All study participants were recommended bariatric surgery. Participants with inflammatory bowel disease, uncontrolled psychiatric disease, moderate to severe gastroesophageal reflux disease, under-substance use, and those with a history of major upper gastrointestinal tract surgery were excluded. Eligible participants were randomly selected for SG or RYGB.

Study findings

A total of 878 and 857 patients underwent SG and RYGB, respectively, in twenty-three hospitals. The study cohort consisted of 74% females and 26% males, and their average age was 42.9 years, with a mean BMI of 40.8. 

A low rate of perioperative complications was observed in both groups without statistical significance. Although aSG was associated with  lower perioperative risk than RYGB, this was not considered clinically relevant due to the existence of other comorbid factors and differential long-term weight control efforts.

A higher number of serious adverse events within 30 days of the procedure was observed in the RYGB group in comparison to the SG group. In randomized studies, a more significant risk difference between groups could be due to selection bias, as healthier patients are more likely to undergo SG. 

Contradictory study outcomes are also affected by the nature of the cohort. For example, the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) study included patients with higher BMI and comorbidities than BEST. Therefore, MBSAQIP was associated with more complicated surgical procedures than BEST. 

The BEST data reflects the possibility that a surgical community with a wider experience of performing RYGB can swiftly shift to SG with low complication rates. However, the possibility of an opposite transition must be reviewed.

As compared to previous assessments on perioperative complications after RYGB, the current study observed small bowel obstruction to be the most common perioperative complication. A higher incidence of small bowel obstruction after RYGB could be linked with the Lönroth surgical technique for RYGB.

The operating time between RYGB and SG was compared, in which a greater operating time was associated with RYGB, which could be due to the greater complexity of this surgical procedure. In both SG and RYGB, the length of post-operative hospitalization was one day after surgery.


The current randomized and large-scale observational study assessed the outcomes of SG and RYGB in individuals with a BMI of 35 to 50. Both surgical procedures were associated with low and insignificantly different perioperative morbidity. The study highlighted that perioperative risk should not be considered a criterion for selecting between SG and RYGB procedures.

Journal reference:
Dr. Priyom Bose

Written by

Dr. Priyom Bose

Priyom holds a Ph.D. in Plant Biology and Biotechnology from the University of Madras, India. She is an active researcher and an experienced science writer. Priyom has also co-authored several original research articles that have been published in reputed peer-reviewed journals. She is also an avid reader and an amateur photographer.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Bose, Priyom. (2024, February 01). Comparing perioperative differences: Sleeve gastrectomy vs. Roux-en-Y gastric bypass. News-Medical. Retrieved on March 05, 2024 from

  • MLA

    Bose, Priyom. "Comparing perioperative differences: Sleeve gastrectomy vs. Roux-en-Y gastric bypass". News-Medical. 05 March 2024. <>.

  • Chicago

    Bose, Priyom. "Comparing perioperative differences: Sleeve gastrectomy vs. Roux-en-Y gastric bypass". News-Medical. (accessed March 05, 2024).

  • Harvard

    Bose, Priyom. 2024. Comparing perioperative differences: Sleeve gastrectomy vs. Roux-en-Y gastric bypass. News-Medical, viewed 05 March 2024,


The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News Medical.
Post a new comment
You might also like...
Understanding obesity's effects on liver metabolism