Comparison of the incidence of cholelithiasis after sleeve gastrectomy and Roux-en-Y gastric bypass in obese patients: a prospective study

Background: Although the risk of cholelithiasis (CL) increases in patients after Roux-en-Y gastric bypass (RYGB), no prospective study has yet assessed the incidence of CL after sleeve gastrectomy (SG). Objectives: To compare, prospectively, the incidence and predictive factors for CL after both procedures. Methods: A postoperative abdominal ultrasound follow-up was proposed to all patients with an intact gallbladder and who underwent RYGB or SG in Hopital Louis Mourier from 2008 onward. Results: At least one ultrasound was performed on one hundred and sixty patients between 6 and 12 months postsurgery, 43 after SG and 117 after RYGB. Age, gender, initial body-mass index, comorbidities were similar in both groups. Weight loss (WL) at 6 months was significantly lower after SG than after RYGB (26.9 +/- 9.2 and 31.3 +/- 7.5 kg, respectively = .001). The incidences of CL after SG and RYGB were similar (28% versus 34% respectively, P = .57). Most cases of CL occurred in the first year post surgery. During the follow-up, 12% and 13% of patients who underwent SG and RYGB, respectively, became symptomatic. WL of >30 kg at 6 months was a risk factor for CL after bariatric surgery, but we did not find any preoperative predictive factor for gallstone formation. Conclusions: Despite lower WL after SG, the incidence of CL after SG and RYGB was similar at 2 years. Our results suggest that rapid WL is the main element leading to gallstone formation after both procedures. (C) 2015 American Society for Metabolic and Bariatric Surgery. All rights reserved.