{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:05:47Z","timestamp":1792785947165,"version":"4.5.0"},"reference-count":35,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:00:00Z","timestamp":1778198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u00b4s Horizon Europe Research and Innovation Programme","award":["101046016"],"award-info":[{"award-number":["101046016"]}],"id":[{"id":"https:\/\/ror.org\/019w4f821","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,23]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Although coronavirus disease 2019 (COVID-19) is no longer a public health emergency, it remains the most prevalent circulating infectious-like illness in Europe. Whether immunocompromising conditions (ICCs) still carry increased mortality risk during the Omicron era is unclear.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a cohort study across EuCARE sites in 8 countries among adults admitted to hospital with COVID-19 between 2020 and 2023. ICCs and COVID-19 pneumonia at hospitalization were defined using clinical information and ICD-10 codes. Logistic regression and counterfactual mediation analysis was used to compare 28-day in-hospital mortality risk associated with ICCs using COVID-19 pneumonia and vaccination at hospital entry as intermediates. Proportion of the total effect of ICCs mediated and the controlled direct effects (CDEs) were calculated. We also formally tested for interaction between SARS-CoV-2 variants and ICCs for mortality risk.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A total of 42 488 individuals were included, of whom 1675 (3.9%) had an ICC. Fifty-five percent were male, and the median age was 67 (IQR, 52\u201379) years. Overall, 4344 (10.2%) individuals died in hospital. ICCs were associated with increased mortality (OR, 1.49 [95% CI, 1.25\u20131.79]), with no evidence for an attenuation during the Omicron phase (P value for interaction = .60). Mediation analyses showed that the total effect of ICCs was mediated by vaccination but only weakly by pneumonia. With Omicron, the excess mortality associated with ICC was higher under the scenario that everyone in the cohort was to develop COVID-19 pneumonia (CDE, 1.22 [95% CI, .09\u20131.65]).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>ICC remains a significant risk factor for in-hospital death, even during the Omicron era, particularly if the infection led to the development of pneumonia.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/infdis\/jiag254","type":"journal-article","created":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T11:46:39Z","timestamp":1778154399000},"page":"e496-e505","source":"Crossref","is-referenced-by-count":0,"title":["Increased In-Hospital Mortality in Immunocompromised Individuals Hospitalized With COVID-19 During the Global Pandemic: A Multinational Cohort Study in the EuCARE Project"],"prefix":"10.1093","volume":"234","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2859-0682","authenticated-orcid":false,"given":"Ashley O","family":"Roen","sequence":"first","affiliation":[{"name":"Centre for Clinical Research, Epidemiology, Modelling and Evaluation, Institute for Global Health, University College London , London ,","place":["United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3153-098X","authenticated-orcid":false,"given":"Pontus","family":"Hedberg","sequence":"additional","affiliation":[{"name":"Department of Medicine Huddinge, Karolinska Institutet , Stockholm ,","place":["Sweden"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-0643-1696","authenticated-orcid":false,"given":"Joana P Ventura","family":"Pereira","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty and University Hospital Duesseldorf, Heinrich Heine University , Duesseldorf ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maurizio","family":"Zazzi","sequence":"additional","affiliation":[{"name":"Department of Medical Biotechnologies, University of Siena, Siena ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7240-4301","authenticated-orcid":false,"given":"Dovile","family":"Juozapaite","sequence":"additional","affiliation":[{"name":"Vilnius Santaros Klinikos Biobank, Vilnius University Hospital Santaros Klinikos , Vilnius ,","place":["Lithuania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milosz","family":"Parczewski","sequence":"additional","affiliation":[{"name":"Department of Infectious, Tropical Diseases and Acquired Immunodeficiency, Pomeranian Medical University, Szczecin ,","place":["Poland"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8277-6288","authenticated-orcid":false,"given":"Jo\u00e3o","family":"Domingos","sequence":"additional","affiliation":[{"name":"Microbiology Laboratory, Department of Infectious Diseases, Unidade Local de Sa\u00fade de Lisboa Ocidental , Lisboa ,","place":["Portugal"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francis","family":"Drobniewski","sequence":"additional","affiliation":[{"name":"Department of Infectious Disease, Imperial College London , London ,","place":["United Kingdom"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4498-4828","authenticated-orcid":false,"given":"Giulia","family":"Marchetti","sequence":"additional","affiliation":[{"name":"Clinic of Infectious Diseases and Tropical Medicine, San Paolo Hospital, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan , Milan ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1713-8682","authenticated-orcid":false,"given":"Luca","family":"Carioti","sequence":"additional","affiliation":[{"name":"Department of Experimental Medicine, University of Rome Tor Vergata , Rome ,","place":["Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pontus","family":"Naucl\u00e9r","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Karolinska University Hospital , Stockholm ,","place":["Sweden"]},{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet , Stockholm ,","place":["Sweden"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8928-3374","authenticated-orcid":false,"given":"Anders","family":"S\u00f6nnerborg","sequence":"additional","affiliation":[{"name":"Department of Medicine Huddinge, Karolinska Institutet , Stockholm ,","place":["Sweden"]},{"name":"Department of Infectious Diseases, Karolinska University Hospital , Stockholm ,","place":["Sweden"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1626-4855","authenticated-orcid":false,"given":"Bj\u00f6rn-Erik Ole","family":"Jensen","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty and University Hospital Duesseldorf, Heinrich Heine University , Duesseldorf ,","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7386-8551","authenticated-orcid":false,"given":"Francesca","family":"Incardona","sequence":"additional","affiliation":[{"name":"EuResist Network GEIE , Via Guido Guinizelli, 98\/100, 00152 Rome ,","place":["Italy"]},{"name":"InformaPRO s.r.l. , Via Guido Guinizelli, 98\/100, 00152 Rome 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