BACKGROUND: Laparoscopic Roux-En-Y Gastric Bypass (LRYGB) contributes significantly to higher weight loss at 6 to 12 months when compared to Laparoscopic Sleeve Gastrectomy (LSG) in patients with severe obesity (SO-body mass index (BMI) ≥ 50 kg/m METHODS: PubMed, EMBASE, and Cochrane Central were searched for studies that compared LRYGB and LSG in SO patients. We pooled outcomes for mortality and complications, defined as bleeding, cardiovascular events, conversion to open procedure, and a composite endpoint of leak, abscess, fistulas, and reoperation. Length of stay and operative time were also pooled. A random-effects model was used, and statistical analyses were performed using R version 4.4.0. RESULTS: A total of 156,767 patients from 28 observational studies were included, of whom 79,324 (50.6%) underwent LRYGB and 77,443 (49.4%) LSG. Length of stay (MD 0.45
95% CI 0.42-0.48
P <
0.01) and operative time (MD 58.88
95% CI 37.88-79.87
P <
0.01) were lower in the LSG group. Overall, there was no difference in mortality (OR 1.28
95% CI 0.80-2.04
P = 0.311) and in complication rates (OR 1.22
95% CI 0.85-1.76
P = 0.287). A subgroup analysis showed lower conversion to open procedure for patients who underwent LSG (OR 2.75
95% CI 1.90-3.98
P <
0.001), and no difference was noted in bleeding (OR 0.98
95% CI 0.47-2.07
P = 0.965), cardiovascular events (OR 0.99
95% CI 0.43-2.29
P = 0.983), and a composite endpoint of leak, abscess, and fistulas (OR 0.82
95% CI 0.67-1.01
P = 0.066). CONCLUSION: Our meta-analysis suggests that there is no difference in mortality and complication rates between the two groups. However, length of stay and operative time were lower in SO patients who underwent LSG.