Cited by 200Bariatric Surgery and OutcomesGallbladder and Bile Duct DisordersBiliary and Gastrointestinal Fistulas

The DOI matches its Crossref record; 46 of the 46 references it cites were found in a registry or an index; 2 of the 28 sources its claims cite were checked for support.

Gallstone Formation Prophylaxis After Gastric Restrictive Procedures for Weight Loss: A Randomized Double-Blind Placebo-Controlled Trial

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Abstract

In Brief 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. This long-term follow-up study was designed to determine if a 6-month regimen of prophylactic ursodeoxycholic acid is effective in the prevention of gallstones after restrictive bariatric surgery. Patients with vertical banded gastroplasty and adjustable gastric banding were enrolled in this study. A daily dose of 500 mg of ursodeoxycholic acid for 6 months is effective prophylaxis for gallstone formation after gastric restrictive procedures.

Overview

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Written from the paper’s full text.

TL;DR

A 6-month regimen of ursodeoxycholic acid 500 mg/d reduced gallstone formation after gastric restrictive bariatric surgery compared with placebo. The benefit persisted at 24 months and was accompanied by fewer cholecystectomies for symptomatic cholelithiasis.

Key findings

  • Gallstone formation was significantly less frequent with ursodeoxycholic acid than placebo at 12 months (3% vs 22%; P = 0.0018, Fisher exact test) and at 24 months (8% vs 30%; P = 0.0022).
  • Over 24 months, cholecystectomy for symptomatic cholelithiasis was performed in 3 ursodeoxycholic acid patients versus 12 placebo patients (4.7% vs 12%; P < 0.02), at a mean of 14.9 ± 4.3 months after bariatric surgery.
  • Preoperative age, sex, weight, BMI, and postoperative weight loss did not differ significantly between groups. Compliance averaged 84% for ursodeoxycholic acid and 79% for placebo; mild/moderate side effects such as nausea and constipation were 9.3% vs 6.6%, with no severe side effects or serious adverse drug reaction withdrawals.
  • The authors conclude that 500 mg/d ursodeoxycholic acid in divided doses for 6 months is effective prophylaxis for gallstone formation after gastric restrictive procedures.

Methods

  • Single-center, randomized, double-blind, placebo-controlled trial in patients undergoing vertical banded gastroplasty (VBG) or adjustable gastric banding (AGB) for morbid obesity; eligibility included age >18 years and BMI ≥40 kg/m², or BMI ≥35 kg/m² with comorbidities. Exclusions included prior cholecystectomy, gallstones, pregnancy/inadequate contraception, and certain concomitant medications.
  • 152 patients were randomized: 76 to placebo and 76 to ursodeoxycholic acid 500 mg/d, beginning within 3 days after surgery and continuing for 6 months or until gallstone development. Follow-up included transabdominal sonography or abdominal CT preoperatively and at 3, 6, 12, and 24 months after surgery or until gallstone formation.
  • Primary efficacy analysis was the proportion developing gallstones in the intent-to-treat for efficacy group (124 patients completed follow-up gallbladder sonography). Statistical testing used Fisher exact test, Wilcoxon-Mann-Whitney-U test, and χ² tests; power calculation assumed 76 patients per group to detect a 20% difference with beta 0.2 and two-sided alpha 0.05.

Limitations

  • The authors report a high dropout rate of 28 patients (18%), possibly related to capsule size, and lower compliance in the VBG group (20 patients, 26%) than in the AGB group (8 patients, 10%). They also note uncertainty about how long ursodeoxycholic acid should be taken and about long-term effectiveness during weight loss.
  • The text makes evident that only 124 of 152 randomized patients were eligible for the intent-to-treat efficacy analysis, and the reported screening/randomization numbers are inconsistent across the abstract and results. Surgical procedure type (VBG vs AGB) was not randomized, limiting subgroup comparisons.

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Integrity signals

Registry

Crossref · 10.1097/01.sla.0000094305.77843.cf

Cites

46 of 46 references verified0 citation errors · 0 not checkable

Statistics

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Verification

Claims the paper makes

10 Own method · 9 No full text of the sources · 9 Own result · 3 Own interpretation · 2 Not checked yet · 1 Partly supported · 1 Couldn’t confirm · accuracy not yet measured

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  • It may state two separate claims as one. 11
  • Probably not a substantial claim. 8
17 of 17
  • The paper relies on this without support.

    Gallstone formation is correlated with weight loss.

    “It is generally accepted that gallstone formation is correlated with weight loss.”
1 of 1

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Citations

Cites

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Research works printed but not linked: 1

  1. Hell, 1998, Long term results with vertical banded gastroplasty in the treatment of morbid obesity., Obes Surg, 8, 373

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Metadata

Authors
Miller, K., Hell, E., Lang, B., & Lengauer, E.
Venue
Annals of Surgery
Published
2003-11
Volume
238
Issue
5
Pages
697-702
ISSN
0003-4932 (ISSN-L)
OpenAlex
W1983687527
Cited by
200
References
45
Citations by year
2026: 9 · 2025: 5 · 2024: 2 · 2023: 15 · 2022: 12 · 2021: 7 · 2020: 19 · 2019: 10 · 2018: 9 · 2017: 7 · 2016: 13 · 2015: 8 · 2014: 12 · 2013: 4 · 2012: 10
FWCI
6.76
Type
journal article
Language
en
Open access
Locations
  • Annals of Surgery (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Surgery › Bariatric Surgery and Outcomes
  • Health Sciences › Medicine › Gastroenterology › Gallbladder and Bile Duct Disorders
  • Health Sciences › Medicine › Gastroenterology › Biliary and Gastrointestinal Fistulas
Keywords
ursodeoxycholic acid, prophylaxis, bariatric surgery, morbid obesity, vertical banded gastroplasty, gastric banding, rapid weight loss, cholecystectomy, gallstone prevention
MeSH terms
Adolescent, Adult, Cholagogues and Choleretics, Double-Blind Method, Female, Humans, Male, Middle Aged, Obesity, Morbid, Postoperative Complications, Prospective Studies, Ursodeoxycholic Acid, Gastroplasty, Cholecystolithiasis, Gallstones

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