{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:02:41Z","timestamp":1792785761123,"version":"4.5.0"},"reference-count":32,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2026,10,11]],"date-time":"2026-10-11T00:00:00Z","timestamp":1791676800000},"content-version":"vor","delay-in-days":69,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006095","name":"South-Eastern Norway Regional Health Authority","doi-asserted-by":"publisher","award":["2023026"],"award-info":[{"award-number":["2023026"]}],"id":[{"id":"10.13039\/501100006095","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006095","name":"South-Eastern Norway Regional Health Authority","doi-asserted-by":"publisher","award":["2024017"],"award-info":[{"award-number":["2024017"]}],"id":[{"id":"10.13039\/501100006095","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Wellcome Leap\u2019s Dynamic Resilience Program","award":["104617"],"award-info":[{"award-number":["104617"]}],"id":[{"id":"https:\/\/ror.org\/03jzgvn02","id-type":"ROR","asserted-by":"crossref"}]},{"name":"Norwegian National Centre for Ageing and Health and Center for Oral Health Services and Research (TkMidt), Trondheim","id":[{"id":"https:\/\/ror.org\/01yb29m74","id-type":"ROR","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100003506","name":"Ministry of Health and Care Services","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003506","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004590","name":"Central Norway Regional Health Authority","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004590","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Tr\u00f8ndelag County Council","award":["NTNU"],"award-info":[{"award-number":["NTNU"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Most studies of delirium occurrence are based on selected hospitalised populations or administrative data. We aimed to estimate the incidence rate of in-hospital delirium in older adults and to assess use of the International Classification of Diseases, 10th Revision (ICD-10) delirium code (F05) in electronic health records.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This population-based cohort study included 9956 participants aged \u226570\u00a0years from HUNT4 70+. Participants were followed from the date of study participation (2017\u201319) until 31 December 2023. In-hospital delirium was identified by retrospective chart review of all admissions during follow-up, using Diagnostic and Statistical Manual of Mental Disorders, fifth edition criteria. Incidence rates were estimated using the first delirium episode per participant, weighted for non-participation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>During follow-up, 1507 participants (15.1%) experienced \u22651 in-hospital delirium episode. The weighted incidence rate was 33.1 (95% CI 31.5\u201334.9) per 1000 person-years and increased with age from 11.4 (age 70\u201374) to 109.0 (age\u2009\u226590) per 1000 person-years. Men had higher incidence rates than women across age groups. Among admissions with delirium, 11.9% had an ICD-10 discharge delirium diagnosis code (F05).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>In-hospital delirium was common, increased markedly with age and was rarely captured by diagnostic coding. Low coding rates suggest that routine health-care data substantially underestimate delirium burden. Under-recognition of delirium may limit opportunities for follow-up in a group at high risk of adverse outcomes. With an ageing population, the burden of delirium is likely to increase for individuals and health-care systems. Our findings support systematic approaches to improve identification and management.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ageing\/afag297","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T11:21:41Z","timestamp":1790594501000},"source":"Crossref","is-referenced-by-count":0,"title":["Population-based incidence rate of in-hospital delirium in older adults in Norway\u2014a HUNT study"],"prefix":"10.1093","volume":"55","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-6424-7701","authenticated-orcid":false,"given":"Wilhelm","family":"Frich","sequence":"first","affiliation":[{"name":"Oslo Delirium Research Group, Institute of Clinical Medicine, University of Oslo , Oslo ,","place":["Norway"]},{"name":"Department of Geriatric Medicine, Oslo University Hospital , Oslo 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,","place":["Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6320-9600","authenticated-orcid":false,"given":"Thomas Andrew","family":"Jackson","sequence":"additional","affiliation":[{"name":"Department of Inflammation and Ageing, Centre for Translational Inflammation Research, Queen Elizabeth Hospital, Mindelsohn Way, University of Birmingham , Birmingham B15 2WD ,","place":["UK"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6741-5516","authenticated-orcid":false,"given":"Gill","family":"Livingston","sequence":"additional","affiliation":[{"name":"Division of Psychiatry, University College London , London, England ,","place":["UK"]},{"name":"St. Pancras Hospital, North London NHS Foundation Trust , London ,","place":["UK"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Myrstad","sequence":"additional","affiliation":[{"name":"Department of Medicine, Levanger Hospital , Nord-Tr\u00f8ndelag Hospital Trust, Levanger, Nord-Tr\u00f8ndelag ,","place":["Norway"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6674-995X","authenticated-orcid":false,"given":"Kenneth","family":"Rockwood","sequence":"additional","affiliation":[{"name":"Department of Medicine, Dalhousie University , Halifax, Nova Scotia ,","place":["Canada"]},{"name":"Nova Scotia Health Frailty and Elderly Care Network , Halifax, Nova Scotia ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geir","family":"Selb\u00e6k","sequence":"additional","affiliation":[{"name":"Oslo Delirium Research Group, Institute of Clinical Medicine, University of Oslo , Oslo ,","place":["Norway"]},{"name":"Department of Geriatric Medicine, Oslo University Hospital , Oslo ,","place":["Norway"]},{"name":"Norwegian National Centre for Ageing and Health, Vestfold Hospital Trust , T\u00f8nsberg ,","place":["Norway"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3067-0016","authenticated-orcid":false,"given":"H\u00e5vard Kjesbu","family":"Skjellegrind","sequence":"additional","affiliation":[{"name":"HUNT Research Centre, Department of Public Health and Nursing, Norwegian University of Science and Technology, Faculty of Medicine and Health Sciences , Levanger ,","place":["Norway"]},{"name":"Levanger Hospital, Levanger, Nord-Tr\u00f8ndelag Hospital Trust , Nord-Tr\u00f8ndelag ,","place":["Norway"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bj\u00f8rn Heine","family":"Strand","sequence":"additional","affiliation":[{"name":"Department of Geriatric Medicine, Oslo University Hospital , Oslo ,","place":["Norway"]},{"name":"Norwegian National Centre for Ageing and Health, Vestfold Hospital Trust , T\u00f8nsberg ,","place":["Norway"]},{"name":"Department of Physical Health and Ageing, Norwegian Institute of Public 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