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A systematic review and meta-analysis of inpatient mortality associated with nosocomial and community COVID-19 exposes the vulnerability of immunosuppressed adults

Ponsford, Mark J., Ward, Tom J. C., Stoneham, Simon M., Dallimore, Clare M., Sham, Davina, Osman, Khalid, Barry, Simon M., Jolles, Stephen, Humphreys, Ian R. ORCID: and Farewell, Daniel ORCID: 2021. A systematic review and meta-analysis of inpatient mortality associated with nosocomial and community COVID-19 exposes the vulnerability of immunosuppressed adults. Frontiers in Immunology 12 , 744696. 10.3389/fimmu.2021.744696

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Background: Little is known about the mortality of hospital-acquired (nosocomial) COVID-19 infection globally. We investigated the risk of mortality and critical care admission in hospitalised adults with nosocomial COVID-19, relative to adults requiring hospitalisation due to community-acquired infection. Methods: We systematically reviewed the peer-reviewed and pre-print literature from 1/1/2020 to 9/2/2021 without language restriction for studies reporting outcomes of nosocomial and community-acquired COVID-19. We performed a random effects meta-analysis (MA) to estimate the 1) relative risk of death and 2) critical care admission, stratifying studies by patient cohort characteristics and nosocomial case definition. Results: 21 studies were included in the primary MA, describing 8,251 admissions across 8 countries during the first wave, comprising 1513 probable or definite nosocomial COVID-19, and 6738 community-acquired cases. Across all studies, the risk of mortality was 1.3 times greater in patients with nosocomial infection, compared to community-acquired (95% CI: 1.005 to 1.683). Rates of critical care admission were similar between groups (Relative Risk, RR=0.74, 95% CI: 0.50 to 1.08). Immunosuppressed patients diagnosed with nosocomial COVID-19 were twice as likely to die in hospital as those admitted with community-acquired infection (RR=2.14, 95% CI: 1.76 to 2.61). Conclusions: Adults who acquire SARS-CoV-2 whilst already hospitalised are at greater risk of mortality compared to patients admitted following community-acquired infection; this finding is largely driven by a substantially increased risk of death in individuals with malignancy or who had undergone transplantation. These findings inform public health and infection control policy and argue for individualised clinical interventions to combat the threat of nosocomial COVID-19, particularly for immunosuppressed groups.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Medicine
Additional Information: This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY)
Publisher: Frontiers Media
ISSN: 1664-3224
Funders: This work was partly funded by UKRI/NIHR through the UK Coronavirus Immunology Consortium (UK-CIC). MP is supported by the Welsh Clinical Academic Training (WCAT) programme and a Career Development Award from the Association of Clinical Pathologists and i, performing analysis, or communicating findings. TW is supported by an NIHR Clinical Lectureship. This research was funded in part by the Wellcome Trust. For the purpose of open access, the authors have applied a CC BY public copyright licence to any Author Accepted Manuscript version arising from this submission.
Date of First Compliant Deposit: 22 October 2021
Date of Acceptance: 13 September 2021
Last Modified: 18 May 2023 02:01

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