BACKGROUND: Although cholecystectomy incidence is known to be high after Roux-en-Y gastric bypass (RYGB) surgery, the actual increase in incidence is not known. Furthermore, the outcome of cholecystectomy after RYGB is not known.
OBJECTIVES: To estimate cholecystectomy incidence before and after RYGB and to compare the outcome of post-RYGB cholecystectomy with the cholecystectomy outcome in the background population.
SETTING: Nationwide Swedish multiregister study.
METHODS: The Swedish Register for Cholecystectomy and Endoscopic Retrograde Cholangiopancreatography (n = 79,386) and the Scandinavian Obesity Surgery Registry (n = 36,098) were cross-matched for the years 2007 through 2013 and compared with the National Patient Register.
RESULTS: The standardized incidence ratio for cholecystectomy before RYGB was 3.42 (2.75-4.26, P<.001); the ratio peaked at 11.4 (10.2-12.6, P<.001) 6-12 months after RYGB, which was 3.54 times the baseline level (2.78-4.49, P<.001). After 36 months, the incidence ratio had returned to baseline. The post-RYGB group demonstrated an increased risk of 30-day postoperative complications after cholecystectomy (odds ratio 2.13, 1.78-2.56; P<.001), including reoperation (odds ratio 3.84, 2.76-5.36; P<.001), compared with the background population. The post-RYGB group also demonstrated a higher risk of conversion, acute cholecystectomy, and complicated gallstone disease and a slightly prolonged operative time, adjusted for age, sex, American Society of Anesthesiologists class, and previous open RYGB.
CONCLUSION: Compared with the background population, the incidence of cholecystectomy was substantially elevated already before RYGB and increased further 6-36 months after RYGB. Previous RYGB doubled the risk of postoperative complications after cholecystectomy and almost quadrupled the risk of reoperation, even when intraoperative cholangiography was normal.