Five-Year Weight Loss Outcomes in Laparoscopic Vertical Sleeve Gastrectomy (LVSG) Versus Laparoscopic Roux-en-Y Gastric Bypass (LRYGB) Procedures: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND: Laparoscopic vertical sleeve gastrectomy (LVSG) has overtaken the laparoscopic Roux-en-Y gastric bypass (LRYGB) as the most frequently performed bariatric surgical procedure. To date little has been reported on the long-term outcomes of the LVSG procedure comparative to the traditionally favoured LRYGB. We undertook a systematic review and meta-analysis to review the 5-year outcomes of comparing LVSG and LRYGB. We undertook a systematic review and meta-analysis to compare 5-year weight loss outcomes of randomized controlled trials comparing LVSG to LRYGB.

MATERIALS AND METHODS: Searches of electronic databases (PubMed, Embase, CINAHL, Cochrane) were undertaken for randomized controlled trials describing weight loss outcomes in adults at 5 years postoperatively. Where sufficient data was available to undertake meta-analysis, the Hartung-Knapp-Sidik-Jonkman estimation method for random effects model was utilized. The review was registered with PROSPERO and reported following in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

RESULTS: Five studies met the inclusion criteria totaling 1028 patients (LVSG=520, LRYGB=508). Moderate but comparable levels of bias were observed within studies. Statistically significant body mass index loss ranged from -11.37 kg/m (range: -6.3 to -15.7 kg/m) in the LVSG group and -12.6 kg/m (range: -9.5 to -15.4 kg/m) for LRYGB at 5 years (P<0.001). Systematic review suggested that LRYGB produced a greater weight loss expressed as percent excess weight and percent excess body mass index loss than LVSG: this was not corroborated in the meta-analysis.

CONCLUSIONS: Five year weight loss outcomes suggest both LRYGB and LVSG are effective in achieving significant weight loss at 5 years postoperatively, however, differences in reporting parameters limit the ability to reliably compare the outcomes using statistical methods. Furthermore, results may be impacted by large dropout rates and per protocol analysis of the 2 largest included studies. Further long-term studies are required to contradict or validate the results of this meta-analysis.