Incidence and risk factors for de novo cholelithiasis after bariatric surgery

Obesity and rapid weight loss after bariatric surgery (BS) are risk factors for the development of cholelitiasis. The aim of this study is to know the incidence of the de novo symptomatic cholelitiasis (DNSC) after BS and to analyze the risk factors for its development. Single-centre retrospective observational study of patients undergoing BS between January 2010 and December 2017. The incidence of DNSC has been studied and sex, age, comorbilities, surgical tecnique, initial BMI and percentage of excess BMI lost (%EIMCP) at 6th, 12th and 24th postoperative months have been analyzed. Among the 415 patients who underwent BS, 280 have been studied since they were not previously cholecystectomized and had a preoperative negative abdominal ultrasound. Twenty-nine developed DNSC (10.35%), with a remarkably higher increase in cumulative incidence during the first postoperative year (5%, 95% CI 2,4-7,6). A higher percentage of excess BMI lost at the 6, 12 and 24 postoperative months was statistically significantly correlated with an increased risk of DNSC. Incidence of DNSC and cholecystectomy after BS are relatively high, mainly during rapid weight loss period and even more the higher the percentage of excess BMI lost is. Concomitant cholecystectomy during BS in case of preoperative cholelithiasis regardless of symptoms and the use of ursodeoxycholic acid during the period of greater risk for DNSC development are two therapeutic options to consider.