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

Abstract 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 Hôpital 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, co-morbidities 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.