Cohort studyindependent cross-checkfull text checked★ key study I-BAR-102 in-depth review

US study: survival after sleeve and bypass

Reduction in Long-term Mortality After Sleeve Gastrectomy and Gastric Bypass Compared to Nonsurgical Patients With Severe Obesity.

Overview

Courcoulas et al.. Ann Surg 2023 · PMID 34387200 · DOI 10.1097/SLA.0000000000005155

Over 5 years, people who had a sleeve died about 70% less often than similar people who did not have surgery (1.0% vs 2.7%).

Does the study support the specific claim? No · Methodological quality: moderate

Study explained simply

What did the researchers want to find out?: Compare deaths after SG/RYGB with matched non-operated patients
How was the study done?: Matched cohort, health records
How many people, animals or samples were studied?: 13,900 SG; 17,258 RYGB; 87,965 controls
What was actually found?: Lower death rates after both operations
How large was the observed effect?: SG HR 0.28 (0.13-0.57)
What do the results mean in everyday life?: Sleeve was not associated with earlier death
What are the study's limitations?: About one third lost to follow-up; observational
What does it say about Elawady's specific claim?: Contradicts "sleeve kills"
Do the results apply to Germany and Europe?: Plausible for Europe and Egypt
What can explicitly not be concluded from this study?: Cannot exclude unmeasured confounding

Authors: Courcoulas et al.
Journal: Ann Surg
Year: 2023
Identifier: PMID 34387200 DOI 10.1097/SLA.0000000000005155
Verification: verified – PubMed efetch 2026-10-26 + Crossref API
Retracted: no
Corrections: none
Extent checked: full text
Conflicts of interest and funding: Funded by NIH/NIDDK R01DK105960; funder had no role. Some authors report research grants outside the work (full text).

Do sleeve gastrectomy and gastric bypass each lower long-term mortality compared with matched patients with severe obesity who did not have surgery?

Study design: Cohort study – Retrospective matched cohort (3 Kaiser Permanente regions), each procedure compared with its own matched nonsurgical controls
Population: Adults 19-79 y, BMI >=35, primary SG or RYGB 2005-2015, and up to 3 matched controls each
Country: USA
Period: 2005-2015
Sample size: 13,900 SG, 17,258 RYGB, 87,965 nonsurgical
Inclusion and exclusion criteria: Excluded <1 y prior enrolment, prior cancer, pregnancy; matched on site, sex, age, BMI, diabetes, insulin, race/ethnicity, comorbidity score, prior utilisation

Exposure / intervention: Sleeve gastrectomy or Roux-en-Y gastric bypass
Comparator: Usual care (very little obesity pharmacotherapy or intensive lifestyle treatment)
Endpoints: All-cause mortality; cardiovascular-, cancer- and diabetes-related mortality
Statistical methods: Cox regression with restricted cubic splines, multiple imputation, many prespecified confounders; E-value sensitivity analysis

Results: 5-y all-cause mortality: SG HR 0.28 (0.13-0.57); RYGB HR 0.43 (0.35-0.54). Unadjusted 5-y cumulative mortality SG 1.02% vs 2.74% controls. At 3 y, SG: cardiovascular death HR 0.33 (0.19-0.58), cancer death HR 0.26 (0.11-0.59), diabetes death HR 0.15 (0.04-0.53). 5-y follow-up rates 70.9% (SG), 72.0% (RYGB), 64.5% (controls).
Absolute risks: Unadjusted 5-y mortality 1.02% after SG vs 2.74% in matched controls (difference ~1.7 percentage points).
Authors' conclusion: Sleeve gastrectomy, like gastric bypass, appears to be associated with lower mortality compared with matched usual-care patients.

Orienting tool: ROBINS-E
Type of assessment: simplified assessment (abstract only)
Full formal assessment: no
Overall risk of bias: some concerns
Rationale: Loss to follow-up and residual confounding; authors quantify robustness with E-values.

HR 0.28 vs crude risk ratio ~0.37 (stats/I-BAR-102_courcoulas_2023.py); CI log-symmetric; wide CI for SG because of few deaths.

Direct evidence that sleeve gastrectomy is associated with lower all-cause and cancer mortality.

Short sleeve follow-up (5 y).

US insured population; biology transferable.

Supports lower mortality after sleeve; moderate certainty.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	moderate
Risk of bias	some concerns
Precision of results	moderate
Directness	direct
Reproducibility	replicated
Consistency with the overall evidence	consistent
Regional transferability	moderate
Adequacy of the interpretation (by the archive)	not applicable

Very long-term (>10 y) sleeve survival.