Body Mass Index and Pneumothorax Risk After CT-Guided Pulmonary Nodule Localization: A Nonlinear Analysis Using Restricted Cubic Splines

Body Mass Index and Pneumothorax Risk After CT-Guided Pulmonary Nodule Localization: A Nonlinear Analysis Using Restricted Cubic Splines | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Body Mass Index and Pneumothorax Risk After CT-Guided Pulmonary Nodule Localization: A Nonlinear Analysis Using Restricted Cubic Splines Junkai Xiong, Chengbin Huang, Jianyang Wu, Yangsheng Ou, Zhizhou Chen, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6489726/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 04 Mar, 2026 Read the published version in Journal of Cardiothoracic Surgery → Version 1 posted 7 You are reading this latest preprint version Abstract Objective: Pneumothorax remains the most frequent complication of CT-guided pulmonary nodule localization, yet the role of body mass index (BMI) is poorly understood. We investigated the nonlinear relationship between BMI and pneumothorax risk using restricted cubic spline (RCS) analysis. Methods: In this retrospective cohort study, 175 patients undergoing CT-guided localization for solitary pulmonary nodules (≤20 mm) were analyzed. Multivariable logistic regression and RCS models adjusted for clinical/procedural confounders identified BMI threshold effects. Results: The overall pneumothorax rate was 34.3% (60/175). RCS revealed a nonlinear relationship (P for nonlinear=0.015), with an inflection point at BMI=24.7 kg/m². Below this threshold, each 1-unit BMI increase reduced pneumothorax risk (OR: 0.65, 95% CI: 0.52–0.82; P<0.001), while no significant association was observed above it (OR: 1.40, 95% CI: 0.97–2.03; P=0.073). Conclusion: BMI exhibits a U-shaped association with pneumothorax risk, with optimal protection at BMI=24.7 kg/m². Thin patients (BMI<24.7 kg/m²) may benefit from refined techniques (e.g., thinner needles, coaxial approach) to mitigate risk. Keywords: Pulmonary nodule; CT-guided localization; Pneumothorax; Obesity paradox; Threshold effect Pulmonary nodule CT-guided localization Pneumothorax Obesity paradox Threshold effect Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 04 Mar, 2026 Read the published version in Journal of Cardiothoracic Surgery → Version 1 posted Editorial decision: Revision requested 18 Sep, 2025 Reviews received at journal 20 Jul, 2025 Reviewers agreed at journal 15 Jul, 2025 Reviewers invited by journal 08 Jul, 2025 Editor assigned by journal 21 Apr, 2025 Submission checks completed at journal 21 Apr, 2025 First submitted to journal 20 Apr, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6489726","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":445354892,"identity":"020cf128-35d1-43bd-a378-1b4cacbe2366","order_by":0,"name":"Junkai Xiong","email":"","orcid":"","institution":"The First Hospital of Putian, Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Junkai","middleName":"","lastName":"Xiong","suffix":""},{"id":445354893,"identity":"57ec9ba7-11b4-4f33-b4a7-88eecaf94583","order_by":1,"name":"Chengbin Huang","email":"","orcid":"","institution":"The First Hospital of Putian, Fujian 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Surgery","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Pulmonary nodule, CT-guided localization, Pneumothorax, Obesity paradox, Threshold effect","lastPublishedDoi":"10.21203/rs.3.rs-6489726/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6489726/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Objective: Pneumothorax remains the most frequent complication of CT-guided pulmonary nodule localization, yet the role of body mass index (BMI) is poorly understood. We investigated the nonlinear relationship between BMI and pneumothorax risk using restricted cubic spline (RCS) analysis.\nMethods: In this retrospective cohort study, 175 patients undergoing CT-guided localization for solitary pulmonary nodules (≤20 mm) were analyzed. Multivariable logistic regression and RCS models adjusted for clinical/procedural confounders identified BMI threshold effects.\nResults: The overall pneumothorax rate was 34.3% (60/175). RCS revealed a nonlinear relationship (P for nonlinear=0.015), with an inflection point at BMI=24.7 kg/m². Below this threshold, each 1-unit BMI increase reduced pneumothorax risk (OR: 0.65, 95% CI: 0.52–0.82; P\u003c0.001), while no significant association was observed above it (OR: 1.40, 95% CI: 0.97–2.03; P=0.073).\nConclusion: BMI exhibits a U-shaped association with pneumothorax risk, with optimal protection at BMI=24.7 kg/m². Thin patients (BMI\u003c24.7 kg/m²) may benefit from refined techniques (e.g., thinner needles, coaxial approach) to mitigate risk.\nKeywords: Pulmonary nodule; CT-guided localization; Pneumothorax; Obesity paradox; Threshold effect","manuscriptTitle":"Body Mass Index and Pneumothorax Risk After CT-Guided Pulmonary Nodule Localization: A Nonlinear Analysis Using Restricted Cubic Splines","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-06 07:40:17","doi":"10.21203/rs.3.rs-6489726/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-09-18T12:11:06+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-20T17:34:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"131342368220769913514578742109754758273","date":"2025-07-15T13:57:31+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-08T10:35:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-22T03:11:47+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-04-22T03:11:22+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Cardiothoracic Surgery","date":"2025-04-20T14:02:27+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-cardiothoracic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcts","sideBox":"Learn more about [Journal of Cardiothoracic Surgery](http://cardiothoracicsurgery.biomedcentral.com)","snPcode":"13019","submissionUrl":"https://submission.nature.com/new-submission/13019/3","title":"Journal of Cardiothoracic Surgery","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"a5674c3c-dd11-4876-b435-10b94f4adb48","owner":[],"postedDate":"June 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-03-09T16:00:44+00:00","versionOfRecord":{"articleIdentity":"rs-6489726","link":"https://doi.org/10.1186/s13019-026-03938-9","journal":{"identity":"journal-of-cardiothoracic-surgery","isVorOnly":false,"title":"Journal of Cardiothoracic Surgery"},"publishedOn":"2026-03-04 15:57:03","publishedOnDateReadable":"March 4th, 2026"},"versionCreatedAt":"2025-06-06 07:40:17","video":"","vorDoi":"10.1186/s13019-026-03938-9","vorDoiUrl":"https://doi.org/10.1186/s13019-026-03938-9","workflowStages":[]},"version":"v1","identity":"rs-6489726","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6489726","identity":"rs-6489726","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}