Effectiveness of bariatric surgical procedures: A systematic review and network meta-analysis of randomized controlled trials

Abstract

Background: Bariatric surgery has proved to be an effective strategy in treating obesity. However, randomized controlled trials (RCTs) of 3 most common bariatric surgery procedures, Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and laparoscopic adjustable gastric band (LAGB), reported inconsistent results. We performed a systematic review and network meta-analysis to synthesize evidence of effectiveness of the 3 common bariatric procedures from relevant RCTs.

Methods: The present study was a systematic review and network meta-analysis of RCTs. All RCTs must meet the following criteria to be included in the analysis: patients with body mass index (BMI) ≥30 kg/m, reported at least 1 outcome of interest, compared at least 2 of the 3 bariatric procedures, and had follow-ups of at least 1 year. Primary outcome was weight loss, expressed as differences in mean BMI reduction and percentage excess weight loss (%EWL) following 1 year after the surgery. Network meta-analysis was based on Bayesian framework with Markov Chain Monte Carlo simulation approach.

Results: Eleven RCTs that met the criteria were included in the review. Of 9 trials (n = 765), the differences in mean BMI reduction were -0.76 (95% CI: -3.1 to 1.6) for RYGB versus SG, -5.8 (95% CI: -9.2 to -2.4) for RYGB versus LAGB, and -5.0 (95% CI: -9.0 to -1.0) for SG versus LAGB. Eight RCTs (n = 656) reported percentage excess weight-loss (%EWL), the mean differences between RYGB and SG, RYGB and LAGB, and SG and LAGB were 3.8% (95% CI: -8.5% to 13.8%), -22.2% (95% CI: -34.7% to -6.5%), and -26.0% (95% CI: -40.6% to -6.4%), respectively. The meta-analysis indicated low heterogeneity between studies, and the node splitting analysis showed that the studies were consistent between direct and indirect comparisons (P > .05).

Conclusion: The RYGB and SG yielded similar in weight-loss effect and both were superior to LAGB. Other factors such as complications and patient preference should be considered during surgical consultations.

Figure 1

The search result. LAGB = laparoscopic adjustable gastric banding, RCT = randomized controlled trial, RYGB = Roux-en-Y gastric bypass, SG = sleeve gastrectomy.

Figure 2

The network of included studies. The circles represent pooled number of studies and the width of bridging bar reflects the number of comparison. LAGB = laparoscopic adjustable gastric banding, RYGB = Roux-en-Y gastric bypass, SD = standard deviation, SG = sleeve gastrectomy.

Figure 3

Forest plots of network meta-analysis results for (A) BMI reduction and (B) %EWL. Open circles indicate mean BMI difference of individual study while closed squares indicate results from the pooled network meta-analysis. The global I² value for the mean BMI reduction analysis was 10.9% (A) and mean %EWL was 0.0% (B). %EWL = percent excess weight loss, BMI = body mass index, CI = confidence interval, LAGB = laparoscopic adjustable gastric banding, RYGB = Roux-en-Y gastric bypass, SD = standard deviation, SG = sleeve gastrectomy.