Evidence map›Paper›PMID 41382010›Full record

ArticleBMC gastroenterology2025

The causal relationship between body mass index and perianal abscess: a Mendelian randomization study.

Long Wu, Huan Wu, Xiao-Yun Li, Yun-Huan Zhen, Hai-Yang Li

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Article in BMC gastroenterology, 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

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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

5 authors.

Long Wu *Department of Colorectal Cancer Center, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou Province, 550001, China.ORCID http://orcid.org/0000-0002-7004-9569
Huan Wu *Department of Infectious Diseases, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou Province, 550001, China.ORCID http://orcid.org/0000-0002-2870-0872
Xiao-Yun LiDepartment of Colorectal Cancer Center, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou Province, 550001, China.
Yun-Huan ZhenDepartment of Colorectal Cancer Center, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou Province, 550001, China.
Hai-Yang LiKey Laboratory of Hepatobiliary and Pancreatic Diseases Treatment and Bioinformatics Research, Department of Hepatobiliary Surgery, Guizhou Medical University, The Affiliated Hospital of Guizhou Medical University, No.28 Guiyi Street, Yunyan District, Guiyang, Guizhou Province, 550001, China. lihaiyang@gmc.edu.cn.ORCID http://orcid.org/0009-0003-4572-1880

Funding

Cultivation Program for General Projects of the National Natural Science Foundation of China gyfynsfc [2023]-01Cultivation Program for Regional Projects of the National Natural Science Foundation of China gyfynsfc [2024]-19General Program of Guizhou Provincial Basic Research Program (Natural Science) QKHJC-zk[2025]-461Key Program of Guizhou Provincial Basic Research Program (Natural Science) QKHJC-ZK[2025]-015Project of Key Laboratory of Diagnosis and Treatment of Hepatobiliary and Pancreatic Diseases and Bioinformatics Research, Guizhou Medical University 2024FY-001Science and Technology Fund Project of Guizhou Health Commission gzwkj2023-042Science and Technology Fund Project of Guizhou Health Commission gzwkj2024-010The Guizhou Provincial Science and Technology Projects QKH JC-ZK [2024]-210
6 · The paper itself

Abstract

backgroundObservational studies suggest an association between elevated body mass index (BMI) and perianal abscess risk, but residual confounding and reverse causality limit causal inference. Mendelian randomization (MR) offers a robust approach to assess causality by leveraging genetic variants as instrumental variables. This study aimed to evaluate the causal relationship between BMI and perianal abscess using a MR framework.

methodsWe analyzed European-ancestry genome-wide association study (GWAS) data for BMI (n = 359,983) and perianal abscess (1,287 cases/182,423 controls). A total of 364 independent SNPs associated with BMI at genome-wide significance (P < 5 × 10⁻⁸) were selected as instrumental variables, with stringent linkage disequilibrium clumping (r² < 0.01, clumping distance > 10,000 kb). Causal estimates were derived using inverse-variance weighted (IVW), MR-Egger, weighted median, and MR-PRESSO methods. Multivariable MR (MVMR) adjusted for lipid metabolism disorders and insulin resistance. Sensitivity analyses assessed pleiotropy, heterogeneity, and instrument strength.

resultsGenetically predicted higher BMI was causally associated with an increased risk of perianal abscess (IVW: OR = 1.94, 95%CI: 1.46-2.68, P = 3.8 × 10⁻⁶). Consistency across methods (MR-Egger: OR = 2.80; weighted median: OR = 2.30) and MVMR adjustment (OR = 1.47, 95%CI: 1.12-1.93) supported robustness. No evidence of directional pleiotropy (MR-Egger intercept P = 0.30) or heterogeneity (I² = 7.6%; MR-PRESSO global test P = 0.148) was observed. Instrument strength was sufficient (mean F-statistic = 37.75), mitigating weak instrument bias.

conclusionThis MR study provides robust genetic evidence supporting BMI as a causal risk factor for perianal abscess. The findings highlight obesity management as a potential preventive strategy, though multifactorial mechanisms warrant further investigation.

Indexed as

AbscessAnus DiseasesBody Mass IndexObesityCausalityFemaleGenome-Wide Association StudyHumansMaleMendelian Randomization AnalysisPolymorphism, Single NucleotideRisk FactorsWhite PeopleBMICausal associationMendelian randomizationPerianal abscessSingle nucleotide polymorphisms

Identifiers

PMID41382010
PMCPMC12817671

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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 OpenQuestion graph.