#5195 MORTALITY OF PATIENTS ON CHRONIC HEMODIALISYS: CAUSED OR RELATED TO SARS-COV-2 INFECTION?

Abstract

Abstract Background and Aims Patients on chronic hemodialysis (HD) treatment had a higher mortality rate than the general population with SARS-CoV-2 infection. The ERA registry showed a 20% mortality at 28 days for these patients. The aim of the study was to evaluate the causes and risk factors of mortality for patients on chronic HD hospitalized with SARS-CoV-2 infection; particularly if the cause of death is directly attributable to the COVID-19 infection or to another pathology. Method Clinical data of chronic HD patients admitted for COVID-19 infection at Fondazione Policlinico Gemelli from March 15th 2020 to February 28th 2022 were analysed. Univariate and multivariate regression analysis for mortality risk factors was performed. Causes of mortality were obtained by hospital discharge forms. COVID-19 related cause of death was defined through intra-hospital codes as COVID-19 pneumonia, COVID-19 ARDS and COVID-19 respiratory failure. Results One hundred and fifty-two chronic HD patients were hospitalized for COVID-19 infection. Table 1 shows the general characteristics of the patients. The 28-day all-cause mortality was 21.9%, wich 11.9% was COVID-19 related. Table 2 shows the cause of mortality. Multivariate Cox regression demonstrated that an increased risk of death from COVID-19 at 28 days was significantly and independently associated with age >73 years (HR 1.05, 95% CI 1.0-1.09; p<0.05), Charlson Comorbidity Index (CCI) > 5 at entry (HR 1.28, 95% CI 1.02-1.60; p<0.01), Continuous Renal Replacement Therapies (CRRT) (HR 2.89, 95% CI 1.03-8.11; p = 0.04) and the presence of peripheral vasculopathy (HR 3.48, 95% CI 1.31-9.27; p = 0.01). Plasma albumin >25 g/L at entry (HR 0.87, 95% CI 0.80-0.96; p<0.01) and pre-admission SARS-CoV-2 vaccination (HR 0.25, 95% CI 0.09-0.72; p = 0.01) significantly reduced the risk of mortality. Conclusion Our study shows that on the total of deaths with a positive COVID-19 test, 59% were caused by the infection while the remaining 41% occurred from other causes. Age, CCI, the presence of peripheral vascular disease and the need for CRRT are independent risk factors for mortality. Vaccination was confirmed as a protective factor.