PREDICTORS OF MORTALITY OF COVID-19 IN HAEMODIALYSIS PATIENTS

ABSTRACT

BACKGROUND AND AIMS: The COVID-19 pandemic has disproportionately affected patients with pre-existing comorbidities, particularly dialysis patients. These patients appear to be more susceptible to severe forms of the infection, due to underlying, coexisting pathologies and their immunocompromised status. The aim of this study was to determine predictors of mortality in this population. METHOD: We conducted an observational, retrospective, cohort study collecting data from the electronic medical records of a single dialysis centre at Hygeia Hospital Tirana, Albania. Baseline patient characteristics, including demographic, clinical and laboratory data were recorded. The receiver operating characteristic (ROC) analysis was used to determine predictors of mortality, their respective sensitivity, specificity and cut-off values. RESULTS: Of 170 haemodialysis patients, 52 were diagnosed with COVID-19. The prevalence of COVID-19 infection in haemodialysis patients in our study was 30.5%. The mean age was 61.5 ± 12.3 years and 65.4% were men. The mortality rate in our cohort was 19.2%. Mortality rates were higher in patients with Diabetic Nephropathy (P < 0.04) and Peripheral Vascular Disease (P < 0.01). High BMI (P < 0.024), high RDW (P < 0.03), elevated C-reactive protein (P < 0.018) and elevated serum ferritin (P < 0.021) levels, were found to be risk factors for severe COVID-19 disease. ROC analysis identified lymphopenia and eosinopenia as the strongest predictors of mortality. AUC for lymphopenia was 0.739. It showed a sensitivity of 80% and a specificity of 85.7%, at a cut-off value of 13.15%. AUC for eosinopenia was 0.814. At a cut-off value of 0.185%, it revealed a sensitivity and specificity of 72.7% and 75%, respectively. CONCLUSION: Our study revealed that risk factors for the development of severe COVID-19 infection were high BMI, high RDW, elevated levels of C-reactive protein (CRP) and serum ferritin. Lymphopenia and eosinopenia were determined as the most important predictors of mortality, in our cohort. Early recognition during the course of the infection, of a declining tendency of lymphocyte and eosinophil counts is paramount, in identifying high-risk patients for severe disease and poor outcomes among haemodialysis patients.