Gallstone formation prophylaxis after gastric restrictive procedures for weight loss: a randomized double-blind placebo-controlled trial.

OBJECT: To determine if a 6-month regimen of prophylactic ursodeoxycholic acid is effective in the prevention of gallstones.

SUMMARY BACKGROUND DATA: Rapid weight loss after surgery for the treatment of morbid obesity is associated with a high incidence of gallstone formation.

METHODS: Patients with vertical banded gastroplasty (VBG) and adjustable gastric banding (AGB) were enrolled in this study. A single-center, randomized, double-blind, prospective trial evaluated 500 mg of ursodeoxycholic acid versus placebo, beginning within 3 days after surgery and continuing for 6 months or until gallstone development, for patients with morbid obesity. Transabdominal sonography or abdominal CT scan was obtained preoperatively at 3, 6, 12, and 24 months after surgery or until gallstone formation.

RESULTS: From March 1997 to April 2000, 262 patients were submitted to surgery. Seventy-seven patients refused to participate in the study; 43 patients with previous gallstone operation or verified gallstones preoperatively were excluded. Of 152 patients, 76 were randomized to placebo and 76 to 500 mg of ursodeoxycholic acid daily. Preoperative age, sex, weight, BMI, and postoperative weight loss were not significantly different between groups. Gallstone formation was significantly less (P = 0.0018, Fisher exact test) frequent with ursodeoxycholic acid than with placebo at 12 months, 3% versus 22%, and 8% versus 30% (P = 0.0022) at 24 months, cholecystectomy in 4.7% versus 12%, respectively (P < 0,02, Fisher exact test).

CONCLUSION: A daily dose of 500 mg of ursodeoxycholic acid for 6 months is effective prophylaxis for gallstone formation following gastric restrictive procedures.