Demographic and Clinical Presentation of Hospitalised Patients with SARS-CoV-2 During the First Omicron Wave

Abstract

Introduction: The objectives of this retrospective study were to describe clinical presentations and mortality outcomes of hospitalised patients with the COVID-19 Omicron variant within two acute district general hospitals, and to evaluate demographic factors associated with these presentations and mortality. Methods: Data was obtained over a month in 2021–2022 from multi-ethnic patients who were hospitalised and detected to have severe acute respiratory syndrome coronavirus 2 Omicron infection. Details included socio-demographic characteristics, vaccination, and mortality. Patients were subdivided into three groups: Group 1 were admitted with true COVID-19 pneumonitis, Group 2 had incidental COVID-19 on admission screening, and Group 3 were negative on admission but developed COVID-19 over 7 days post-admission. Results: Of 553 patients, only 24.1% (133/553) were in Group 1, 58.2% (322/553) in Group 2, and 17.7% (98/553) in Group 3. Patients in Group 1 and Group 3 were significantly older than those in Group 2 (p<0.001). Thirty percent of patients from Black, Asian, and minority ethnic backgrounds had COVID-19 pneumonitis compared with 19% of those with White ethnicity (p=0.002). Twenty percent of patients were admitted within nonmedical specialties, i.e., surgical specialties, paediatrics, and obstetrics. Of 36 requiring critical care, 21 were in Group 1. Of those patients, 20/21 (95%) were unvaccinated and seven of the 21 who died were all unvaccinated (100%). Common COVID-19 presentations included delirium, falls, seizures, chronic obstructive pulmonary disease, and antenatal problems. Overall, 13.7% (76/553) patients died and 4.7% (26/553) were directly attributable to COVID-19. Conclusions: This large, multi-ethnic study has described clinical presentations and mortality of hospitalised patients with Omicron. It has determined socio-demographic factors associated with these presentations, including ethnicity and vaccination rates. The study provides useful information for future COVID-19 studies examining outcomes and presentations of Omicron and future COVID-19 variants.