Evidence mapPaperPMID 41739521Full record

SynthesisBJS open2025

Impact of preoperative weight-loss interventions on outcomes after elective non-bariatric surgery: meta-analysis.

Danni Wang, Simon J A Buczacki, Qiufeng Gu, Zhengmei Liao, Yanli Jiang, Sam West, Dimitrios A Koutoukidis

Abstract readMeta-AnalysisSystematic Review
In one paragraph

Synthesis in BJS open, 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

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Danni WangDepartment of Health Promotion and Behaviour Sciences, Anhui Medical University, Hefei, China.ORCID 0000-0002-1273-8403
Simon J A BuczackiNuffield Department of Surgical Sciences, University of Oxford, Oxford, UK.
Qiufeng GuDepartment of Health Promotion and Behaviour Sciences, Anhui Medical University, Hefei, China.
Zhengmei LiaoDepartment of Health Promotion and Behaviour Sciences, Anhui Medical University, Hefei, China.
Yanli JiangDepartment of Health Promotion and Behaviour Sciences, Anhui Medical University, Hefei, China.
Sam WestNuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
Dimitrios A KoutoukidisNuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.

Funding

Cancer Research UK C14094/A27178China Scholarship Council 202309090006National Institute for Health Research NIHR302549The Pharsalia TrustUniversity of Oxford
6 · The paper itself

Abstract

backgroundObesity disproportionately affects patients awaiting elective non-bariatric surgery and complicates perioperative management. This systematic review aimed to assess the impact of weight-loss interventions on intraoperative and postoperative outcomes.

methodsMEDLINE, Embase, CINAHL, and Web of Science databases were searched from inception to October 2025 for trials on weight-loss interventions. Two reviewers independently screened the studies, extracted relevant data, and assessed risk of bias. Pooled mean differences (MDs), standardized mean differences (SMDs), and odds ratios (ORs) were obtained from random-effects meta-analyses.

resultsThirty-five studies with 9378 participants (mean(standard deviation) age 58(8) years; body mass index 35.6(6.4) kg/m2; 61% women) were included. The median duration of intervention was 8 (interquartile range 4-14) weeks. Preoperative weight-loss interventions were significantly associated with a reduction in overall postoperative complications (odd ratio (OR) 0.63, 95% confidence interval (c.i.) 0.43 to 0.93; I² = 32%) and in complications requiring medical intervention graded as Clavien-Dindo ≥ II (OR 0.66, 0.51 to 0.86; I² = 0%). Additionally, they were linked to a decreased risk of postoperative non-infectious wound-related complications (OR 0.38, 0.15 to 0.97; I2 = 0%), and with reduced intraoperative blood loss in gastrectomy (SMD -0.98, 95% c.i. -1.47 to -0.48; I2 = 0%) and hepatectomy (SMD -0.41, -0.82 to 0.00; I2 = 0%). Reductions in blood transfusion (OR 0.49, 0.31 to 0.79; I² = 0%), hospital readmission rates (OR 0.57, 0.47 to 0.70; I² = 0%), and length of hospital stay (SMD -0.08, -0.13 to -0.04; I² = 0%) were also noted. No association was observed for surgical site infection, venous thromboembolism, or return to the emergency department. Compared with standard care or no intervention, weight-loss interventions led to greater weight loss (MD -3.92 (95% c.i. -5.44 to -2.39) kg; I2 = 91%), and fat mass loss (MD -4.78 (-6.49 to -3.06) kg; I2 = 0%) but no change in lean mass (SMD -0.25, -0.51 to 0.01; I2 = 0%). In a sensitivity analysis of studies at low risk of bias, the estimates and precision of most outcomes did not change materially.

conclusionDespite heterogeneity in study design and surgical populations, the evidence consistently demonstrated that weight-loss interventions are feasible, safe, and can reduce postoperative complications across various surgical specialties alongside improving many outcomes.

Indexed as

Elective Surgical ProceduresObesityPostoperative ComplicationsPreoperative CareWeight LossBody Mass IndexHumansTreatment Outcome

Identifiers

PMID41739521
PMCPMC13223571

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.