Abstract: Open access Original research Timothy Eden,1,2 Shane McAuliffe ‍ ‍,2,3 Dominic Crocombe,2 Jonathan Neville,1 Sumantra Ray2,4,5,6 To cite: Eden T, McAuliffe S, Crocombe D, et al. Nutritional parameters and outcomes in patients admitted to intensive care with COVID-19: a retrospective single-­ centre service evaluation. BMJ Nutrition, Prevention & Health 2021;0. doi:10.1136/ bmjnph-2021-000270 ►► Additional supplemental material is published online only. To view, please visit the journal online (http://​dx.d​ oi.​org/​10.​ 1136/​bmjnph-​2021-0​ 00270). For numbered affiliations see end of article. Correspondence to Dr Timothy Eden, ICU West, Hammersmith Hospital, Imperial College Healthcare NHS Trust, London W12 0HS, UK; ​timothy.​eden@n​ hs.​net Received 13 March 2021 Accepted 12 July 2021 © Author(s) (or their employer(s)) 2021. Re-­use permitted under CC BY-­NC. No commercial re-­use. See rights and permissions. Published by BMJ. Background COVID-19 is an inflammatory syndrome caused by novel coronavirus SARS-­CoV-2. Symptoms range from mild infection to severe acute respiratory distress syndrome (ARDS) requiring ventilation and intensive care. At the time of data collection, UK cases were around 300 000 with a fatality rate of 13% necessitating over 10 000 critical care admissions; now there have been over 4 million cases. Nutrition is important to immune function and influences metabolic risk factors such as obesity and glycaemic control, as well as recovery from acute illnesses. Poor nutritional status is associated with worse outcomes in ARDS and viral infections, yet limited research has assessed pre-­morbid nutritional status and outcomes in patients critically unwell with COVID-19. Objectives Investigate the effect of body mass index (BMI), glycaemic control and vitamin D status on outcomes in adult patients with COVID-19 admitted to an intensive care unit (ICU). Methods Retrospective review of all patients admitted to a central London ICU between March and May 2020 with confirmed COVID-19. Electronic patient records data were analysed for patient demographics; comorbidities; admission BMI; and serum vitamin D, zinc, selenium and haemoglobin A1c (HbA1c) concentrations. Serum vitamin D and HbA1c were measured on admission, or within 1 month of admission to ICU. Primary outcome of interest was mortality. Secondary outcomes included time intubated, ICU stay duration and ICU-­related morbidity. Results Seventy-­two patients; 54 (75%) men, mean age 57.1 (±9.8) years, were included. Overall, mortality was 24 (33%). No significant association with mortality was observed across BMI categories. In the survival arm admission, HbA1c (mmol/mol) was lower, 50.2 vs 60.8, but this was not statistically significant. Vitamin D status did not significantly associate with mortality (p=0.131). However, 32% of patients with low vitamin D (<25 IU/L) died, compared with 13% of patients with vitamin D levels >26 IU/L. Serum zinc and selenium, and vitamin B12 and folate levels were measured in 46% and 26% of patients, respectively. Discussion/conclusion Increased adiposity and deranged glucose homeostasis may potentially increase risk of COVID-19 infection and severity, possibly relating to impaired lung and metabolic function, increased proinflammatory and prothrombotic mechanisms. Vitamin What this paper adds ►► This snapshot audit in a London ICU from the first peak of the COVID-19 pandemic adds to the body of evidence associating..