Morbidity and Mortality of Acute Renal Failure in COVID-19 Patients in Intensive Care According to Waves/Variant: Case of the Grand Hôpital de l’Est Francilien Site de Meaux

Abstract

Introduction: The incidence of acute renal failure (ARF) varies between 20% and 40% of cases for COVID-19 patients admitted to the intensive care unit, with very high mortality, but heterogeneous according to the different epidemic waves, probably due to the genetic variant phenomenon of the virus. The aim of this study is to determine the morbidity and mortality of COVID-19 patients admitted with ARF to the intensive care unit of the Grand H?pital Est Francilien (GHEF) according to the waves and variants. Methods: Cross-sectional observational study of COVID-19 patients with ARF admitted to the intensive care unit of the GHEF site in Meaux covering the period from March 1 st 2020 to December, 31 st 2021. Per-hospitalisation and outcome data were collected and analysed with SPSS version 25.0 software using the Chi-square or Fischer’s exact test or Student’s t-test and logistic regression for p < 0.05. Results: A total of 86 patients were included. The mean age was higher (70 ± 8.5) in patients in the fourth wave than in the other waves (p = 0.015), with male predominance in all waves without significant difference. Co-morbidities: hypertension, diabetes, heart disease, dyslipidaemia and arrhythmia complete with fibrillation were present in all waves. The majority of patients were classified as KDIGO 1 for the different waves (1st: 61.9%, 2nd: 86.5%, 3rd: 80%, and 4th: 75%), with the same trend according to variant (alpha: 80%, beta: 75%, delta: 81.3%, omicron: 75%). Mortality by the wave was: 1st: 28.5%, 2nd: 37.5%, 3rd: 23% and 4th: 11%) and by variant: alpha: 24.2%, beta: 44.8%, delta: 20.7%, omicron: 10.3%). Overall mortality was 33.7%. Case fatality was higher in the fourth wave. Hypertension, shock, failure to recover renal function, acute lung oedema, ventilator-associated lung disease and hyperkalaemia were factors associated with mortality (p < 0.001). Conclusion: Acute renal failure is common in COVID-19 patients admitted to the intensive care unit, and mortality is not negligible. The beta variants and the second wave presented more cases of renal impairment, although the mechanism is still unknown. Further studies are needed to understand this mechanism and perhaps to be able to identify the cause.