The Impact of the Elixhauser Comorbidity Index on Length of Stay in Patients with Coronary Atherosclerotic Heart Disease

The Impact of the Elixhauser Comorbidity Index on Length of Stay in Patients with Coronary Atherosclerotic Heart Disease | 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 The Impact of the Elixhauser Comorbidity Index on Length of Stay in Patients with Coronary Atherosclerotic Heart Disease Wenting Yan, Shuanggui Tian, Yong Xiao, Guodong Xu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8715067/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 16 You are reading this latest preprint version Abstract Objectives To investigate the impact of the Elixhauser Comorbidity Index (ECI) on length of stay (LOS) among patients with coronary atherosclerotic heart disease (CAD). Methods A retrospective analysis was conducted using CAD patient data from the Hubei Provincial Traditional Chinese Medicine Comprehensive Statistics Platform between December 2013 and June 2024. Data on demographics, comorbidities, and surgical status were collected. The comorbidity burden was assessed using the ECI as modified by Walraven et al. Factors associated with LOS were identified using the Kruskal-Wallis H test and Mann-Whitney U test. A Gamma regression model was constructed for multivariable analysis to identify independent factors influencing LOS, and a sensitivity analysis was performed to verify the robustness of the results. Results 22,626 CAD patients were included, with a median LOS of 9 (6,13) days. Univariate analysis showed statistically significant differences in LOS across age groups (Kruskal-Wallis H = 613.131, df = 3, < 0.001), mode of admission (Kruskal-Wallis H = 15.106, df = 2, P = 0.001), mode of discharge (Kruskal-Wallis H = 137.157, df = 2, < 0.001), surgical status (Mann-Whitney U = 16,470,870.000, Z = -7.989, < 0.001), treatment categories (Kruskal-Wallis H = 1510.879, df = 2, < 0.001), and ECI groups (Kruskal-Wallis H = 291.185, df = 3, < 0.001). Gamma regression analysis revealed that, after adjusting for confounding factors, ECI was an independent predictor of LOS ( < 0.001). Patients with ECI scores of 1–3 (Exp(B) = 1.100, 95% CI = 1.064–1.138, < 0.001) and 4–8 (Exp(B) = 1.029, 95% CI = 1.003–1.055, = 0.026) had LOS prolonged by 10.0% and 2.9% respectively, while the ECI ≥ 9 group showed no statistical significance (Exp(B) = 1.009, 95% CI = 0.985–1.034, = 0.479). Sensitivity analysis revealed that after excluding patients with extremely long LOS, the ECI ≥ 9 group reached statistical significance ( = 0.027), indicating that the impact of a high comorbidity burden on LOS became more evident after removing outlier interference. Conclusion ECI is an independent influencing factor for LOS in CAD patients. Clinical practice should emphasize individualized management of patients with a high comorbidity burden to shorten LOS and improve medical resource utilization efficiency. Coronary Atherosclerotic Heart Disease Elixhauser Comorbidity Index Length of Stay Gamma Regression Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 06 May, 2026 Reviews received at journal 14 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviews received at journal 07 Apr, 2026 Reviews received at journal 05 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviewers agreed at journal 31 Mar, 2026 Reviews received at journal 28 Mar, 2026 Reviewers agreed at journal 24 Mar, 2026 Reviewers invited by journal 24 Mar, 2026 Editor assigned by journal 23 Mar, 2026 Editor invited by journal 27 Feb, 2026 Submission checks completed at journal 27 Feb, 2026 First submitted to journal 27 Feb, 2026 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. 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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-8715067","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":611938274,"identity":"660a5d98-49bd-4bff-9cfc-d32c9fd95d3f","order_by":0,"name":"Wenting Yan","email":"","orcid":"","institution":"Hubei University of Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Wenting","middleName":"","lastName":"Yan","suffix":""},{"id":611938275,"identity":"1d32f50d-6b7d-4a1e-9342-d846cc6587cd","order_by":1,"name":"Shuanggui Tian","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBUlEQVRIiWNgGAWjYPACCQYG9saGAx8bDkD4PAR1JAC18BxufDiTBC0gi9ybjXmJ0SI/I/fYY94fFvLmEoxt0rY77iT2TzvA+OBtG4O8OQ4tBjfy0o15EiQMd85ubJPOPfMsccbtBGbDuW0MhjsbcGiRyDGTBmph3HDnIFBL2+HEDdIJbNK8bQwJBgdwOQyixX7DjcQ2aUuIFvbf+LQw3IBoSQRqaTZmhNrCjE+LwZk3ZpJz0iSSN5w52Piwt+2Z8Yzbic2Sc85JGG7A5bD2HDOJNzZ1thuOtz848LPtjmz/7OSDH96U2cjjdBgQMKHFAmMDAzg94AGMP/BKj4JRMApGwYgHAKvkYeebVJgsAAAAAElFTkSuQmCC","orcid":"","institution":"Hubei University of Chinese Medicine","correspondingAuthor":true,"prefix":"","firstName":"Shuanggui","middleName":"","lastName":"Tian","suffix":""},{"id":611938276,"identity":"fa383187-4c63-4fcc-bfdc-11cdd075427b","order_by":2,"name":"Yong Xiao","email":"","orcid":"","institution":"Hubei University of Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Yong","middleName":"","lastName":"Xiao","suffix":""},{"id":611938277,"identity":"ccb9343d-ce33-42d7-a32e-c5e1bfa5fc64","order_by":3,"name":"Guodong Xu","email":"","orcid":"","institution":"Hubei University of Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Guodong","middleName":"","lastName":"Xu","suffix":""}],"badges":[],"createdAt":"2026-01-28 01:23:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8715067/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8715067/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105566474,"identity":"136a5b08-62cd-4e70-b77c-0ce32ce11754","added_by":"auto","created_at":"2026-03-27 12:56:28","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":393970,"visible":true,"origin":"","legend":"","description":"","filename":"TheImpactoftheElixhauserComorbidityIndexonLengthofStayinPatientswithCoronaryAtheroscleroticHeartDisease.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8715067/v1_covered_0b8cfc15-2565-4511-9148-c9b6069bcf63.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The Impact of the Elixhauser Comorbidity Index on Length of Stay in Patients with Coronary Atherosclerotic Heart Disease","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Coronary Atherosclerotic Heart Disease, Elixhauser Comorbidity Index, Length of Stay, Gamma Regression","lastPublishedDoi":"10.21203/rs.3.rs-8715067/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8715067/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjectives\u003c/h2\u003e \u003cp\u003eTo investigate the impact of the Elixhauser Comorbidity Index (ECI) on length of stay (LOS) among patients with coronary atherosclerotic heart disease (CAD).\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA retrospective analysis was conducted using CAD patient data from the Hubei Provincial Traditional Chinese Medicine Comprehensive Statistics Platform between December 2013 and June 2024. Data on demographics, comorbidities, and surgical status were collected. The comorbidity burden was assessed using the ECI as modified by Walraven et al. Factors associated with LOS were identified using the Kruskal-Wallis H test and Mann-Whitney U test. A Gamma regression model was constructed for multivariable analysis to identify independent factors influencing LOS, and a sensitivity analysis was performed to verify the robustness of the results.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003e22,626 CAD patients were included, with a median LOS of 9 (6,13) days. Univariate analysis showed statistically significant differences in LOS across age groups (Kruskal-Wallis H\u0026thinsp;=\u0026thinsp;613.131, df\u0026thinsp;=\u0026thinsp;3, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026lt;\u0026thinsp;0.001), mode of admission (Kruskal-Wallis H\u0026thinsp;=\u0026thinsp;15.106, df\u0026thinsp;=\u0026thinsp;2, P\u0026thinsp;=\u0026thinsp;0.001), mode of discharge (Kruskal-Wallis H\u0026thinsp;=\u0026thinsp;137.157, df\u0026thinsp;=\u0026thinsp;2, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026lt;\u0026thinsp;0.001), surgical status (Mann-Whitney U\u0026thinsp;=\u0026thinsp;16,470,870.000, Z = -7.989, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026lt;\u0026thinsp;0.001), treatment categories (Kruskal-Wallis H\u0026thinsp;=\u0026thinsp;1510.879, df\u0026thinsp;=\u0026thinsp;2, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026lt;\u0026thinsp;0.001), and ECI groups (Kruskal-Wallis H\u0026thinsp;=\u0026thinsp;291.185, df\u0026thinsp;=\u0026thinsp;3, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026lt;\u0026thinsp;0.001). Gamma regression analysis revealed that, after adjusting for confounding factors, ECI was an independent predictor of LOS (\u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026lt;\u0026thinsp;0.001). Patients with ECI scores of 1\u0026ndash;3 (Exp(B)\u0026thinsp;=\u0026thinsp;1.100, 95% CI\u0026thinsp;=\u0026thinsp;1.064\u0026ndash;1.138, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e\u0026lt;\u0026thinsp;0.001) and 4\u0026ndash;8 (Exp(B)\u0026thinsp;=\u0026thinsp;1.029, 95% CI\u0026thinsp;=\u0026thinsp;1.003\u0026ndash;1.055, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e= 0.026) had LOS prolonged by 10.0% and 2.9% respectively, while the ECI\u0026thinsp;\u0026ge;\u0026thinsp;9 group showed no statistical significance (Exp(B)\u0026thinsp;=\u0026thinsp;1.009, 95% CI\u0026thinsp;=\u0026thinsp;0.985\u0026ndash;1.034, \u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e= 0.479). Sensitivity analysis revealed that after excluding patients with extremely long LOS, the ECI\u0026thinsp;\u0026ge;\u0026thinsp;9 group reached statistical significance (\u003cspan class=\"InlineEquation\"\u003e\u003c/span\u003e=\u0026thinsp;0.027), indicating that the impact of a high comorbidity burden on LOS became more evident after removing outlier interference.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eECI is an independent influencing factor for LOS in CAD patients. Clinical practice should emphasize individualized management of patients with a high comorbidity burden to shorten LOS and improve medical resource utilization efficiency.\u003c/p\u003e","manuscriptTitle":"The Impact of the Elixhauser Comorbidity Index on Length of Stay in Patients with Coronary Atherosclerotic Heart Disease","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-26 07:20:44","doi":"10.21203/rs.3.rs-8715067/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-06T09:37:17+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-14T08:28:42+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T08:21:21+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-07T15:44:56+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-06T01:52:55+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"336999739013815623573087550570097319202","date":"2026-04-02T07:35:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"230381667875747055645523167544368434615","date":"2026-03-31T14:51:14+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"268758186535382594241124698278820608390","date":"2026-03-31T11:23:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"159612635467441098128645044788041415489","date":"2026-03-31T09:07:34+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-28T12:47:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"36589257193814664925466917826092029491","date":"2026-03-24T19:47:29+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-24T13:32:24+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-23T08:14:16+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-02-27T18:37:26+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-27T11:08:47+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Cardiovascular Disorders","date":"2026-02-27T07:52:22+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-cardiovascular-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcar","sideBox":"Learn more about [BMC Cardiovascular Disorders](http://bmccardiovascdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcar/default.aspx","title":"BMC Cardiovascular Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"c7686b58-4869-4e88-8fc9-5d2f6476f8bb","owner":[],"postedDate":"March 26th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-06T09:37:17+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-19T04:08:51+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-26 07:20:44","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8715067","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8715067","identity":"rs-8715067","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}