Probiotics administration following sleeve gastrectomy surgery: a randomized double-blind trial

Background: Probiotics are commonly used after bariatric surgery; however, uncertainty remains regarding their efficacy. Our aim was to compare the effect of probiotics vs placebo on hepatic, inflammatory and clinical outcomes following laparoscopic sleeve gastrectomy (LSG). Methods: This randomized, double-blind, placebo-controlled, trial of 6-month treatment with probiotics (Bio-25; Supherb) vs placebo and 6 months of additional follow-up was conducted among 100 morbidly obese nonalcoholic fatty liver disease (NAFLD) patients who underwent LSG surgery. The primary outcome was a reduction in liver fat content, measured by abdominal ultrasound, and secondary outcomes were improvement of fibrosis, measured by shear-wave elastography, metabolic and inflammatory parameters, anthropometrics and quality of life (QOL). Fecal samples were collected and analyzed for microbial composition. Results: One hundred patients (60% women, mean age of 41.9±9.8 years and body mass index of 42.3±4.7 kg m −2 ) were randomized, 80% attended the 6-month visit and 77% completed the 12-month follow-up. Fat content and NAFLD remission rate were similarly reduced in the probiotics and placebo groups at 6 months postsurgery (−0.9±0.5 vs −0.7±0.4 score; P =0.059 and 52.5 vs 40%; P =0.262, respectively) and at 12 months postsurgery. Fibrosis, liver-enzymes, C-reactive protein (CRP), leptin and cytokeratin-18 levels were significantly reduced and QOL significantly improved within groups ( P ⩽0.014 for all), but not between groups ( P ⩾0.173 for all) at 6 and 12 months postsurgery. Within-sample microbiota diversity (alpha-diversity) increased at 6-month postsurgery compared with baseline in both study arms ( P ⩽0.008) and decreased again at 12 months postsurgery compared with 6 months postsurgery ( P ⩽0.004) but did not reach baseline values. Conclusions: Probiotics administration does not improve hepatic, inflammatory and clinical outcomes 6- and 12 months post-LSG.