Meta-analysisindependent cross-checkabstract checked I-BAR-137 standard review
Meta-analysis: gallstones after sleeve vs bypass
Comparative Risk of Gallstone Formation After Sleeve Gastrectomy and Roux-En-Y Gastric Bypass: A Systematic Review and Meta-Analysis.
Overview
Silva-Chavez et al.. Obes Surg 2025 · PMID 41251897 · DOI 10.1007/s11695-025-08388-1
Gallstones formed after both operations; in the short term they were somewhat less common after sleeve.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Gallstones SG vs RYGB
- How was the study done?
Meta-analysis
- How many people, animals or samples were studied?
195,665
- What was actually found?
OR 0.68
- How large was the observed effect?
OR 0.68
- What do the results mean in everyday life?
Both operations raise gallstone risk
- What are the study's limitations?
Fragile
- What does it say about Elawady's specific claim?
Partly supports
- Do the results apply to Germany and Europe?
Applicable
- What can explicitly not be concluded from this study?
Risk vs no surgery
Scientific in-depth review
1. Full reference
- Authors
- Silva-Chavez et al.
- Journal
- Obes Surg
- Year
- 2025
- Identifier
- PMID 41251897 DOI 10.1007/s11695-025-08388-1
- Verification
- verified – PubMed efetch 2026-10-26 + Crossref API
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
COI statement (PubMed record): Declarations. Competing Interests: The authors declare no competing interests.
2. Research question
Is gallstone formation more frequent after SG or RYGB?
3. Study design and population
- Study design
- Meta-analysis – Systematic review and meta-analysis of observational studies
- Population
Patients after SG or RYGB
- Country
Multinational
- Period
not stated in abstract
- Sample size
10 studies, 195,665 patients
- Inclusion and exclusion criteria
Observational studies reporting incident cholelithiasis
4. Methods and endpoints
- Exposure / intervention
SG
- Comparator
RYGB
- Endpoints
Incident gallstones
- Statistical methods
DerSimonian-Laird OR; subgroup and influence analyses
5. Actual results
- Results
SG vs RYGB OR 0.68 (0.53-0.88; I2 75%); <2 y follow-up OR 0.59 (0.42-0.82); >=2 y OR 0.84 (0.55-1.28). Excluding the largest study: OR 0.31 (0.03-2.72), I2 99%.
- Absolute risks
not reported in abstract
- Authors' conclusion
SG is associated with lower short-term gallstone risk than RYGB, but results are heterogeneous and sensitive.
6. Strengths
- Large sample
7. Weaknesses
- Fragile to one study
- Observational
8. Risk of bias
- Orienting tool
- AMSTAR 2
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Abstract only.
9. Assessment of the statistical interpretation
Not robust in influence analysis.
10. Relevance to the specific claim
Gallstones occur after both procedures; sleeve does not appear worse than bypass.
11. Independent contrary findings
12. Transferability to Germany and Europe
International.
13. Overall methodological judgement
Limits a sleeve-specific excess claim.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | some concerns |
| Precision of results | low |
| Directness | direct |
| Reproducibility | unknown |
| Consistency with the overall evidence | inconsistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Comparison with non-surgical weight loss.
15. Linked fact checks
- Sleeve gastrectomy causes gallstones (stones form faster after sleeve/rapid weight loss). – Studies with mixed or unclear results