Outcomes of Covid-19 Infection among Hospitalized Patients by Their Stage of Chronic Kidney Disease

ABSTRACT

INTRODUCTION: Chronic kidney disease (CKD) is an important risk factor for severe COVID-19 disease associated with increased intensive care unit (ICU) admission and mortality. Studies demonstrate an increased mortality rate among advancing CKD stages in patients without COVID-19 infection. However, it is unknown whether a graded association exists between the stages of CKD and COVID-19 mortality. We aim to compare the rates of ICU admission, mechanical ventilation (MV), and survival amongst COVID-19 patients with Stage IIIb -V CKD. METHOD(S) We conducted a retrospective cohort study on non-dialysis adults with Stages IIIb, IV, and V CKD without previous renal transplant hospitalized for COVID-19 infection in a community hospital. Patients were categorized into two groups, Stage IIIb CKD and Stages IV&V CKD, based on their pre-admission glomerular filtration rate (GFR 30-44ml/ min vs < 30ml/min). The primary endpoints were rates of ICU admission, MV, non-invasive mechanical ventilation (NIMV), and survival. The Mann-Whitney U test for continuous variables and the chi-square test for categorical variables were used for analysis. RESULT(S) We screened 228 patients and 153 met the inclusion criteria. Baseline demographics were distributed equally between the two groups. There were statistically significant differences in the ICU admission rate (45.2% vs 25.3%,p-0.01), MV rate (37.1% vs 16.5%,p-0.004) and NIMV rate (50% vs 28.6%,p-0.007) in patients with Stage IIIb versus Stages IV&V CKD respectively. However, there was no significant difference in the survival rates (79.1% vs 67.7%,p-0.1128) between the two groups. CONCLUSION(S) The association between reduced baseline eGFR and increased risk of severe COVID-19 infection has been established with multiple studies evaluating the prognostic impact of pre-existing CKD in patients with COVID-19. Our study illustrates the greater incidence of adverse outcomes, such as ICU admission rate, MV rate, and NIMV rate, in patients with Stages IV&V CKD versus Stage IIIb CKD. With recent guidelines recommending management of COVID-19 infection based on the presence of risk factors, these results will aid in risk stratification among CKD patients with COVID-19, and encourage future prospective studies to explore disease-modifying treatments for the vulnerable CKD population.