Weight loss outcomes in laparoscopic vertical sleeve gastrectomy (LVSG) versus laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures: a meta-analysis and systematic review of randomized controlled trials

Purpose: Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic vertical sleeve gastrectomy (LVSG), have been proposed as cost effective strategies to manage morbid obesity. This aim of this meta-analysis was to compared the postoperative weight loss outcomes reported in randomised control trials (RCTs) for LVSG versus LRYGB procedures. Material and Methods: RCTs comparing the weight loss outcomes following LVSG and LRYGB in adult population between January 2000 and November 2015 were selected from PubMed, Medline, Embase, Science Citation Index, Current Contents, and the Cochrane database. The review was prepared in accordance with Preferred Reporting of Systematic Reviews and Meta-Analyses (PRISMA). Results: Nine unique RCTs described over 10 publications involving a total of 865 patients (LVSG n=437, LRYGB n=428) were analyzed. Postoperative follow up ranged from 3 months to 5 years. Twelve-month excess weight loss for LVSG ranged from 69.7% to 83%, and for LRYGB, ranged from 60.5% to 86.4%. A number of studies reported slow weight gain between the 2nd and 3rd years of postoperative follow-up ranging from 1.4 to 4.2% EWL. This trend was seen to continue to 5 years postoperatively (8% to 10% EWL) for both procedures. Conclusions: In conclusion, LRYGB and LVSG are comparable with regards to the weight loss outcomes in the short term, with LRYGB appearing achieving slightly greater weight loss. Slow weight recidivism is observed after the first postoperative year following both procedures. Long-term reporting of outcomes obtained from well-designed studies using ITT analyses are identified as a major gap in the literature at present.