Evidence mapPaperPMID 41217501Full record

ArticleBiomolecules & biomedicine2025

Bariatric metabolic surgery and cancer risk: Target trial emulation using iterative time distribution matching.

Jazeel Abdulmajeed, Zumin Shi, Manar E Abdel-Rahman, Fakhar Shahid, Mohammed F Alam, Mashael Al-Shafai, Muhammad E H Chowdhury, Abdullah Shaito, Adedayo A Onitilo, Suhail A Doi

Abstract read
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Article in Biomolecules & biomedicine, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Jazeel AbdulmajeedDepartment of Population Medicine, College of Medicine, QU Health, Qatar University, Doha, Qatar; Business and Health Intelligence Department, Primary Health Care Corporation, Doha, Qatar.
Zumin ShiDepartment of Nutrition Sciences, College of Health Sciences, QU Health, Qatar University, Doha, Qatar.
Manar E Abdel-RahmanDepartment of Public Health, College of Health Sciences, QU Health, Qatar University, Doha, Qatar.
Fakhar ShahidDepartment of Bariatric and Metabolic Surgery, Hamad Medical Corporation, Doha, Qatar.
Mohammed F AlamDepartment of Public Health, College of Health Sciences, QU Health, Qatar University, Doha, Qatar.
Mashael Al-ShafaiDepartment of Biomedical Sciences, College of Health Sciences, QU Health, Qatar University, Doha, Qatar; Biomedical Research Center (BRC), QU Health, Qatar University, Doha, Qatar.
Muhammad E H ChowdhuryDepartment of Electrical Engineering, Qatar University, Doha, Qatar.
Abdullah ShaitoBiomedical Research Center (BRC), QU Health, Qatar University, Doha, Qatar.
Adedayo A OnitiloMarshfield Clinic Health System, Inc. Marshfield Medical Center, Wisconsin, USA; Wisconsin NCI Community Oncology Research Program (WiNCORP), University of Wisconsin, Wisconsin, USA.
Suhail A DoiDepartment of Population Medicine, College of Medicine, QU Health, Qatar University, Doha, Qatar.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Bariatric metabolic surgery (BMS) is a common intervention for severe obesity, yet its effects on cancer risk remain unclear. Observational studies and meta-analyses yield inconsistent findings, while randomized controlled trials often lack adequate follow-up to evaluate cancer outcomes. This study aims to emulate a target trial using observational data, employing a transparent and robust methodology to address this issue. We constructed a large retrospective cohort of adults with obesity in Qatar using electronic medical records from the public health system, with data available from 2018. We developed and applied iterative time distribution matching (ITDM) which is an iterative version of prescription time distribution matching (PTDM) as an improved approach to mitigate immortal time bias. This adaptation facilitated the alignment of time-zero (T0) between BMS recipients and non-recipients. Subsequently, we applied a Cox proportional hazards regression model, controlling for confounders and prognostic covariates, for data analysis. The final study cohort comprised 124,780 individuals aged 30 years and older, including 1,465 who underwent BMS and 1,583 who developed cancer during the follow-up period. The median follow-up duration was 7.79 years (IQR: 4.89-10.85). In the confounder- and prognostic covariate-adjusted Cox model, BMS was associated with a reduced hazard of cancer (HR 0.49, 95% CI 0.31 to 0.76). Given potential residual confounding and the limited outcome data, these findings provide preliminary evidence of a protective association and should be interpreted cautiously. This approach emphasizes transparency in trial emulation design, and future studies should focus on specific cancer types and long-term outcomes as additional data become available.

Indexed as

Bariatric SurgeryNeoplasmsAdultFemaleHumansMaleMiddle AgedObesityProportional Hazards ModelsQatarRetrospective StudiesRisk Factors

Identifiers

PMID41217501
PMCPMC12873741

What Socratic holds

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.