Severe COVID-19 and Diabetes - A Retrospective Cohort Study from Three London Teaching Hospitals

ABSTRACT Patients with diabetes mellitus admitted to hospital with COVID-19 caused by infection with the novel coronavirus (SARS-CoV-2) have poorer outcomes. However, the drivers for this are not fully elucidated. We performed a retrospective cohort study, including detailed pre-hospital and presenting clinical and biochemical factors of 889 patients diagnosed with COVID-19 in three constituent hospitals of a large London NHS Trust. 62% of patients with severe COVID-19 were of non-White ethnic backgrounds and the prevalence of diabetes was 38%. 323 (36%) patients met the primary outcome of death or admission to the intensive care unit (ICU) within 30 days of diagnosis. Male gender, advancing age and the Clinical Frailty Scale, an established measure of multimorbidity, independently predicted poor outcomes on multivariate analysis. Diabetes did not confer an independent risk for adverse outcomes in COVID-19, although patients with diabetes and ischaemic heart disease were at particular risk. Additional risk factors which significantly and independently associated with poorer outcomes in patients with diabetes were age, male gender and lower platelet count. Antiplatelet medication was associated with a lower risk of death/ICU admission and should be evaluated in randomised clinical trials amongst high risk patient groups.