{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,26]],"date-time":"2026-05-26T11:06:10Z","timestamp":1779793570368,"version":"3.53.1"},"reference-count":55,"publisher":"BMJ","issue":"5","license":[{"start":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T00:00:00Z","timestamp":1779667200000},"content-version":"unspecified","delay-in-days":24,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,4,21]]},"published-print":{"date-parts":[[2026,5]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>This study aimed to identify potential significant statistical associations between the development of delirium, medication and several other patient-specific factors across a 10-year retrospective longitudinal real-world dataset.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>A retrospective, population-based cohort study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>The National University Hospital of Iceland.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>All patients\u226518 years hospitalised between 2010 and 2020.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Primary and secondary outcome measures<\/jats:title>\n                    <jats:p>The primary outcome was a diagnosis of delirium within 2 years of a patient filling a prescription for a specific medication. The exposure was pre-admission medication use or a pre-existing condition. Secondary outcomes included mortality, length of hospital stay, readmission rate and frequency of additional delirium diagnosis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 85\u2009942 admissions and readmissions were included in the dataset, which comprised 1066 variables. The cohort comprised 55\u2009495\u2009patients (51.5% male) with a median [IQR] age of 71 years [58, 82]. Throughout the study, 3533\u2009patients were diagnosed with delirium at least once over the 10-year study period. A statistically significant association (\u03c7\n                      <jats:sup>2<\/jats:sup>\n                      test,\n                      <jats:italic>p<\/jats:italic>\n                      &lt;0.001) between the delirium (n=3533) and the non-delirium group (n=51\u2009926) was identified for hyperpolypharmacy (\u226510 medications), prescribed proton pump inhibitors, opioids, beta-lactam antibiotics, anticoagulants, statins and selective beta-blockers. Delirium was associated with an extended hospital stay, an increased readmission rate and increased mortality. No significant statistical association was found between delirium and the use of tricyclic antidepressants (p=0.121), nor with the presence of type I diabetes (p=0.216). On an annual average, the prevalence of patients who had obtained a delirium diagnosis within the previous year and were subsequently diagnosed again with delirium during their admission was 25.7%.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Numerous medications and other patient-specific risk factors have been identified, which underlines the complexity of delirium development. To strengthen patient safety and hinder the development of delirium, an increased emphasis is needed to review medication use and improve our understanding of medication risk associated with delirium cause, treatment and prevention. Specific prescribing\/deprescribing advice should be developed to inform prescribing practice and patient safety.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2025-108215","type":"journal-article","created":{"date-parts":[[2026,5,26]],"date-time":"2026-05-26T09:05:13Z","timestamp":1779786313000},"page":"e108215","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Exploring the association between medication, patient-specific factors and delirium in hospitalised patients: a 10-year retrospective, population-based cohort study in Iceland"],"prefix":"10.1136","volume":"16","author":[{"given":"Anita E","family":"Weidmann","sequence":"first","affiliation":[{"name":"Department of Clinical Pharmacy, Universit\u00e4t Innsbruck, Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia A","family":"Schintler","sequence":"additional","affiliation":[{"name":"Department of Clinical Pharmacy, Universit\u00e4t Innsbruck, Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reto","family":"Stauffer","sequence":"additional","affiliation":[{"name":"Department of Statistics & Digital Science Centre, University of Innsbruck, Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7054-0844","authenticated-orcid":false,"given":"Martin I","family":"Sigur\u00f0sson","sequence":"additional","affiliation":[{"name":"Division of Anaesthesia and Intensive Care Medicine, Landspitali -The National University Hospital of Iceland, Reykjav\u00edk, Iceland"},{"name":"Faculty of Medicine, University of Iceland, Reykjav\u00edk, Iceland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9232-6723","authenticated-orcid":false,"given":"Freyja","family":"J\u00f3nsd\u00f3ttir","sequence":"additional","affiliation":[{"name":"Faculty of Pharmaceutical Sciences, University of Iceland, Reykjav\u00edk, Iceland"},{"name":"Pharmacy Services, Landspitali -The National University Hospital of Iceland, Reykjav\u00edk, \u00cdsland, Iceland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,5,26]]},"reference":[{"key":"2026052603470730000_16.5.e108215.1","doi-asserted-by":"crossref","DOI":"10.3390\/ijms21072397","article-title":"Treatment of Delirium in Older Persons: What We Should Not Do!","volume":"21","author":"Lauretani","year":"2020","journal-title":"Int J Mol Sci"},{"key":"2026052603470730000_16.5.e108215.2","unstructured":"MdL RE , Schoo C , Delirium PM . 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