Characterisation of in-hospital complications associated with COVID-19 using the ISARIC WHO Clinical Characterisation Protocol UK: a prospective, multicentre cohort study

Background COVID-19 is a multisystem disease and patients who survive might have in-hospital complications. These complications are likely to have important short-term and long-term consequences for patients, health-care utilisation, health-care system preparedness, and society amidst the ongoing COVID-19 pandemic. Our aim was to characterise the extent and effect of COVID-19 complications, particularly in those who survive, using the International Severe Acute Respiratory and Emerging Infections Consortium WHO Clinical Characterisation Protocol UK. Methods We did a prospective, multicentre cohort study in 302 UK health-care facilities. Adult patients aged 19 years or older, with confirmed or highly suspected SARS-CoV-2 infection leading to COVID-19 were included in the study. The primary outcome of this study was the incidence of in-hospital complications, defined as organ-specific diagnoses occurring alone or in addition to any hallmarks of COVID-19 illness. We used multilevel logistic regression and survival models to explore associations between these outcomes and in-hospital complications, age, and pre-existing comorbidities. Findings Between Jan 17 and Aug 4, 2020, 80 388 patients were included in the study. Of the patients admitted to hospital for management of COVID-19, 49.7% (36 367 of 73 197) had at least one complication. The mean age of our cohort was 71.1 years (SD 18.7), with 56.0% (41 025 of 73 197) being male and 81.0% (59 289 of 73 197) having at least one comorbidity. Males and those aged older than 60 years were most likely to have a complication (aged >= 60 years: 54.5% [16 579 of 30 416] in males and 48.2% [11 707 of 24 288] in females; aged <60 years: 48.8% [5179 of 10 609] in males and 36.6% [2814 of 7689] in females). Renal (24.3%, 17 752 of 73 197), complex respiratory (18.4%, 13 486 of 73 197), and systemic (16.3%, 11 895 of 73 197) complications were the most frequent. Cardiovascular (12.3%, 8973 of 73 197), neurological (4.3%, 3115 of 73 197), and gastrointestinal or liver (0.8%, 7901 of 73 197) complications were also reported. Interpretation Complications and worse functional outcomes in patients admitted to hospital with COVID-19 are high, even in young, previously healthy individuals. Acute complications are associated with reduced ability to self-care at discharge, with neurological complications being associated with the worst functional outcomes. COVID-19 complications are likely to cause a substantial strain on health and social care in the coming years. These data will help in the design and provision of services aimed at the post-hospitalisation care of patients with COVID-19. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.