Objective: The aim of this study was to compare weight loss, obesity-related comorbidities, and biochemical outcomes of LSG versus LRYGB through a meta-analysis of randomized controlled trials (RCTs).
Summary of background data: LSG and LRYGB are the 2 most commonly performed bariatric surgeries for the treatment of obesity. The comparative outcomes of the 2 surgeries is a topic of ongoing debate and medium-term outcomes remain uncertain.
Methods: A search for RCTs comparing LRYGB versus LSG was conducted. Pooled outcomes between 2 procedures were compared using pairwise random-effects meta-analysis at 1, 3, and 5-year follow-up time points. Grading of recommendations, assessment, development, and evaluation was used to assess certainty of evidence.
Results: Thirty-three studies involving 2475 patients were included. LRYGB resulted in greater loss of body mass index compared to LSG at 1 year [mean difference -1.25 kg/m, 95% confidence interval (CI) -2.01 to -0.49, P = 0.001; moderate certainty of evidence] which persisted at 3 years, but there was insufficient evidence at 5 years. Resolution of dyslipidemia was higher for LRYGB than LSG at 1 year (risk ratio 0.58, 95% CI 0.46-0.73, P < 0.001; moderate certainty of evidence) and 5 years (risk ratio 0.68, 95%CI 0.46-0.99, P = 0.04; low certainty of evidence). There was no difference between LRYGB and LSG for remission of type 2 diabetes, hypertension, and hemoglobin A1c, fasting insulin, homeostatic model assessment of insulin resistance, high-density lipoprotein, and the rate of 30-day major and minor complications.
Conclusions: There are insufficient data from RCTs to draw any conclusions regarding the long-term comparative effectiveness beyond 3 years between LRYGB and LSG.