Differences in the effects of laparoscopic sleeve gastrectomy and laparoscopic Roux-en-Y gastric bypass on gut hormones: systematic and meta-analysis

Surg Obes Relat Dis. 2021 Feb;17(2):444-455. doi: 10.1016/j.soard.2020.10.018. Epub 2020 Oct 19.


Background: Laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures are becoming more popular in the world of bariatric surgery.

Objectives: This study investigates how LSG and LRYGB affect gut hormones and examines their differences.

Setting: Systematic review and meta-analysis.

Methods: The literature was retrieved from PubMed, Web of Science, Embase, and the Cochrane Library database before April 2020.

Results: We included 53 articles in our meta-analysis. After bariatric surgery, the patients' ghrelin, fasting acyl-ghrelin, fasting peptide YY (PYY), and their AUC in the LSG group were significantly lower than those in LRYGB group. Fasting ghrelin levels were significantly reduced in patients who received LSG. After LRYGB, the postoperative fasting PYY was higher than at baseline, and the results were statistically significant. Additionally, we found an increase in fasting ghrelin levels after LRYGB. Lastly, insulin levels were both reduced after LSG and LRYGB with no significant difference.

Conclusions: In terms of gut hormones, ghrelin decreased significantly after LSG, while PYY increased after LRYGB. However, the impacts caused by the change in gut hormones after undergoing either LSG and LRYGB on patients are complicated, therefore, the results should be interpreted cautiously.

Keywords: Ghrelin; Laparoscopic Roux-en-Y gastric bypass; Laparoscopic sleeve gastrectomy; Meta-analysis; Peptide YY.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Gastrectomy
  • Gastric Bypass*
  • Ghrelin / analogs & derivatives
  • Humans
  • Laparoscopy*
  • Obesity, Morbid* / surgery
  • Treatment Outcome


  • Ghrelin
  • acyl-ghrelin