{"paper_id":"081e4da0-8684-4c8e-960c-1c64306f3a8b","body_text":"Pharmacogenomic Medicine Use and Adverse Outcomes in Hospitalised Older Patients: A Retrospective Cross-Sectional Study | 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 Article Pharmacogenomic Medicine Use and Adverse Outcomes in Hospitalised Older Patients: A Retrospective Cross-Sectional Study Victoria David, Ciarán McInerney, Justine Tomlinson, Eleanor Bryant, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6317260/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 28 Jan, 2026 Read the published version in The Pharmacogenomics Journal → Version 1 posted 10 You are reading this latest preprint version Abstract This study aimed to assess the prevalence of pharmacogenomic medicine usage upon hospital admission in patients aged 65 and over and evaluate its association with adverse outcomes, including length of stay, unplanned admissions, and repeat hospital admissions. A retrospective cross-sectional study was conducted using hospital admissions data from 2018-2019 in one NHS hospital trust in England, focusing on patients aged 65 and over. Pharmacogenomic medicine usage was examined, and comparisons were made between the prevalence of pharmacogenomic use in unplanned and planned admissions. Multivariable models assessed whether pharmacogenomic medicine use was associated with adverse outcomes, considering frailty status. Analysis of 59,973 admissions revealed 67 pharmacogenomics medicines as per the Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines, with 11 classified as high-risk among 1,438 unique medicines identified from 560,179 recorded medications. Notably, unplanned admissions exhibited a higher prevalence of pharmacogenomic medicine use (84% versus 64%, p<0.001) compared to planned admissions. The models demonstrated that pharmacogenomic medicine usage was associated with adverse outcomes (length of stay in hospital, unplanned admission and repeat hospital admission) with substantial evidence (Delta_AICc < 2) particularly in patients with high frailty status. This study highlights the association between pharmacogenomic medicine usage for adverse outcomes, particularly among patients with high frailty. The findings emphasise the importance of integrating pharmacogenomic-guided care into the management of older individuals with frailty to mitigate adverse outcomes and enhance medication safety. Health sciences/Health care/Health services Health sciences/Health care/Geriatrics Figures Figure 1 Full Text Additional Declarations There is NO conflict of interest to disclose. Supplementary Files SupplementaryData.docx Supplementary Tables Cite Share Download PDF Status: Published Journal Publication published 28 Jan, 2026 Read the published version in The Pharmacogenomics Journal → Version 1 posted Editorial decision: revise 23 Jun, 2025 Review # 2 received at journal 21 May, 2025 Review # 1 received at journal 01 May, 2025 Reviewer # 2 agreed at journal 15 Apr, 2025 Reviewer # 1 agreed at journal 05 Apr, 2025 Reviewers invited by journal 01 Apr, 2025 Submission checks completed at journal 31 Mar, 2025 First submitted to journal 30 Mar, 2025 Unknown event 27 Mar, 2025 Editor assigned by journal 27 Mar, 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6317260\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Article\",\"associatedPublications\":[],\"authors\":[{\"id\":436769394,\"identity\":\"26dd8a64-42b7-42c7-80a0-5ffae4a86ca0\",\"order_by\":0,\"name\":\"Victoria David\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA40lEQVRIiWNgGAWjYHACAyBiljOAsC3AFGMDEVqMDRiYQWwJYrUwMCduAGthIEKLwQHmjZ95CqzTt7P3H93wo0CCgb+9gU1yBl4tbMXSPAbpuTt7DrPd7AE6TOLMATbJDXi0SDbwGEjOMDicu+FGMtsNHqAWA4kENskH+LUY/wRqSTcAarn5hxgt/Aw8ZhIfDA4ngLTchtuCz2H8DGxlFh8M0g03nDlsdlvGQIJH4szBZkt83mdjYN58I+GPtbzB8cZnN9/8sZHjb28+eLMHjxYGeTRn8xCOyFEwCkbBKBgFBAEAZDBFul8rOz8AAAAASUVORK5CYII=\",\"orcid\":\"https://orcid.org/0000-0002-0273-314X\",\"institution\":\"University of Bradford, Bradford\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Victoria\",\"middleName\":\"\",\"lastName\":\"David\",\"suffix\":\"\"},{\"id\":436769395,\"identity\":\"7ef0c1b8-23fc-4014-a034-978ace24a491\",\"order_by\":1,\"name\":\"Ciarán McInerney\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Ciarán\",\"middleName\":\"\",\"lastName\":\"McInerney\",\"suffix\":\"\"},{\"id\":436769396,\"identity\":\"73451ff3-eb43-428c-9b8a-28da07a34b3d\",\"order_by\":2,\"name\":\"Justine Tomlinson\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Justine\",\"middleName\":\"\",\"lastName\":\"Tomlinson\",\"suffix\":\"\"},{\"id\":436769397,\"identity\":\"eb392508-9302-4291-99ff-f6742f6eb43c\",\"order_by\":3,\"name\":\"Eleanor Bryant\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Eleanor\",\"middleName\":\"\",\"lastName\":\"Bryant\",\"suffix\":\"\"},{\"id\":436769398,\"identity\":\"50a3441e-9f99-4f5a-9f3d-17980dbb090b\",\"order_by\":4,\"name\":\"Gurdeep Sagoo\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Gurdeep\",\"middleName\":\"\",\"lastName\":\"Sagoo\",\"suffix\":\"\"},{\"id\":436769399,\"identity\":\"7d1420f9-92a6-4b98-baea-149139778023\",\"order_by\":5,\"name\":\"V-Lin Cheong\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"V-Lin\",\"middleName\":\"\",\"lastName\":\"Cheong\",\"suffix\":\"\"},{\"id\":436769400,\"identity\":\"b29cf43d-26a4-423d-99cd-df8dfb74588f\",\"order_by\":6,\"name\":\"Heather Smith\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Heather\",\"middleName\":\"\",\"lastName\":\"Smith\",\"suffix\":\"\"},{\"id\":436769401,\"identity\":\"6ae64029-d718-4a43-82ea-ff4c791cdf8a\",\"order_by\":7,\"name\":\"Beth Fylan\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0003-0599-4537\",\"institution\":\"University of Bradford\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Beth\",\"middleName\":\"\",\"lastName\":\"Fylan\",\"suffix\":\"\"},{\"id\":436769402,\"identity\":\"c2cdb497-c7bb-46a6-8972-11343a084a0d\",\"order_by\":8,\"name\":\"Marcus Rattray\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Marcus\",\"middleName\":\"\",\"lastName\":\"Rattray\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2025-03-27 06:00:13\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-6317260/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-6317260/v1\",\"draftVersion\":[],\"editorialEvents\":[{\"content\":\"https://doi.org/10.1038/s41397-026-00396-3\",\"type\":\"published\",\"date\":\"2026-01-28T05:00:00+00:00\"}],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":81940601,\"identity\":\"02dbbfa8-cf8e-44ba-9122-7f3505b44d77\",\"added_by\":\"auto\",\"created_at\":\"2025-05-05 06:57:29\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":41686,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eThe distribution of total medicines. (a) used per admission to hospital (b) used by patients with unplanned admissions compared to patients with planned admissions (Chi-square test χ2(2, N =59973) = 770.021, p\\u0026lt;0.001). The distribution of PGx medicines (c) used per admission to hospital (d) in patients unplanned admissions compared to patients with planned admissions (Chi-square test χ2(2, N =59973) = 93.459, p\\u0026lt;0.001). The coloured bars show the proportion of the total number of patients in each group according to numbers of PGx medicines used (grouped).\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"1.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-6317260/v1/03b4a068ab1ca76fa2ad26bc.png\"},{\"id\":101391625,\"identity\":\"72b7ae04-78cd-4a6a-991f-f65554c1efe2\",\"added_by\":\"auto\",\"created_at\":\"2026-01-29 08:36:55\",\"extension\":\"pdf\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":536529,\"visible\":true,\"origin\":\"\",\"legend\":\"Article File\",\"description\":\"\",\"filename\":\"tPjManuscriptVD.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-6317260/v1_covered_7e1a6a98-01a0-4bfc-b4aa-15de66183ae7.pdf\"},{\"id\":81940604,\"identity\":\"8c034510-182b-46df-9012-978cf8214c48\",\"added_by\":\"auto\",\"created_at\":\"2025-05-05 06:57:29\",\"extension\":\"docx\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"supplement\",\"size\":225160,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eSupplementary Tables\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"SupplementaryData.docx\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-6317260/v1/5403c58aa357b03b2d202ebc.docx\"}],\"financialInterests\":\"There is \\u003cb\\u003eNO\\u003c/b\\u003e conflict of interest to disclose.\",\"formattedTitle\":\"Pharmacogenomic Medicine Use and Adverse Outcomes in Hospitalised Older Patients: A Retrospective Cross-Sectional Study\",\"fulltext\":[],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":false,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":true,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":true,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"the-pharmacogenomics-journal\",\"isNatureJournal\":false,\"hasQc\":false,\"allowDirectSubmit\":false,\"externalIdentity\":\"tpj\",\"sideBox\":\"Learn more about [The Pharmacogenomics Journal](http://www.nature.com/tpj/)\",\"snPcode\":\"41397\",\"submissionUrl\":\"https://mts-tpj.nature.com/cgi-bin/main.plex\",\"title\":\"The Pharmacogenomics Journal\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"ejp\",\"reportingPortfolio\":\"Nature AJ\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false},\"keywords\":\"\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-6317260/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-6317260/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"This study aimed to assess the prevalence of pharmacogenomic medicine usage upon hospital admission in patients aged 65 and over and evaluate its association with adverse outcomes, including length of stay, unplanned admissions, and repeat hospital admissions. A retrospective cross-sectional study was conducted using hospital admissions data from 2018-2019 in one NHS hospital trust in England, focusing on patients aged 65 and over. Pharmacogenomic medicine usage was examined, and comparisons were made between the prevalence of pharmacogenomic use in unplanned and planned admissions. Multivariable models assessed whether pharmacogenomic medicine use was associated with adverse outcomes, considering frailty status. Analysis of 59,973 admissions revealed 67 pharmacogenomics medicines as per the Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines, with 11 classified as high-risk among 1,438 unique medicines identified from 560,179 recorded medications. Notably, unplanned admissions exhibited a higher prevalence of pharmacogenomic medicine use (84% versus 64%, p\\u003c0.001) compared to planned admissions. The models demonstrated that pharmacogenomic medicine usage was associated with adverse outcomes (length of stay in hospital, unplanned admission and repeat hospital admission) with substantial evidence (Delta_AICc \\u003c 2) particularly in patients with high frailty status. This study highlights the association between pharmacogenomic medicine usage for adverse outcomes, particularly among patients with high frailty. The findings emphasise the importance of integrating pharmacogenomic-guided care into the management of older individuals with frailty to mitigate adverse outcomes and enhance medication safety.\",\"manuscriptTitle\":\"Pharmacogenomic Medicine Use and Adverse Outcomes in Hospitalised Older Patients: A Retrospective Cross-Sectional Study\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2025-05-05 06:57:24\",\"doi\":\"10.21203/rs.3.rs-6317260/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"revise\",\"date\":\"2025-06-23T14:35:08+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"This content is not available.\",\"date\":\"2025-05-21T19:57:31+00:00\",\"index\":2,\"fulltext\":\"This content is not available.\"},{\"type\":\"editorInvitedReview\",\"content\":\"This content is not available.\",\"date\":\"2025-05-01T11:39:57+00:00\",\"index\":1,\"fulltext\":\"This content is not available.\"},{\"type\":\"reviewerAgreed\",\"content\":\"This content is not available.\",\"date\":\"2025-04-15T15:07:05+00:00\",\"index\":2,\"fulltext\":\"This content is not available.\"},{\"type\":\"reviewerAgreed\",\"content\":\"This content is not available.\",\"date\":\"2025-04-05T07:06:37+00:00\",\"index\":1,\"fulltext\":\"This content is not available.\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2025-04-01T08:58:05+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2025-03-31T11:22:28+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"The Pharmacogenomics Journal\",\"date\":\"2025-03-30T17:22:22+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksFailed\",\"content\":\"\",\"date\":\"2025-03-27T13:30:44+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2025-03-27T05:59:26+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"the-pharmacogenomics-journal\",\"isNatureJournal\":false,\"hasQc\":false,\"allowDirectSubmit\":false,\"externalIdentity\":\"tpj\",\"sideBox\":\"Learn more about [The Pharmacogenomics Journal](http://www.nature.com/tpj/)\",\"snPcode\":\"41397\",\"submissionUrl\":\"https://mts-tpj.nature.com/cgi-bin/main.plex\",\"title\":\"The Pharmacogenomics Journal\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"ejp\",\"reportingPortfolio\":\"Nature AJ\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"823a6c7a-361a-4abc-b4fc-a4d0bc5fcbbe\",\"owner\":[],\"postedDate\":\"May 5th, 2025\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"published-in-journal\",\"subjectAreas\":[{\"id\":46505484,\"name\":\"Health sciences/Health care/Health services\"},{\"id\":46505485,\"name\":\"Health sciences/Health care/Geriatrics\"}],\"tags\":[],\"updatedAt\":\"2026-01-29T08:36:49+00:00\",\"versionOfRecord\":{\"articleIdentity\":\"rs-6317260\",\"link\":\"https://doi.org/10.1038/s41397-026-00396-3\",\"journal\":{\"identity\":\"the-pharmacogenomics-journal\",\"isVorOnly\":false,\"title\":\"The Pharmacogenomics Journal\"},\"publishedOn\":\"2026-01-28 05:00:00\",\"publishedOnDateReadable\":\"January 28th, 2026\"},\"versionCreatedAt\":\"2025-05-05 06:57:24\",\"video\":\"\",\"vorDoi\":\"10.1038/s41397-026-00396-3\",\"vorDoiUrl\":\"https://doi.org/10.1038/s41397-026-00396-3\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-6317260\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-6317260\",\"identity\":\"rs-6317260\",\"version\":[\"v1\"]},\"buildId\":\"8U1c8b4HqxoKbykW_rLl7\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}