ABSTRACT
Background: Maintenance dialysis patients' SARS-CoV-2 receptor binding spike antibody (RBD s-Ab) levels decline rapidly in the months following initial vaccination. We describe the association of RBD s-Ab levels with a subsequent diagnosis of COVID-19 and COVID-related hospitalization or death. Method(s): We identified all vaccinated adult maintenance dialysis patients at Dialysis Clinic, Inc. who were diagnosed with COVID-19 between June 20, 2021 and May 8, 2022. Descriptive analyses illustrate the association of RBD s-Ab levels assessed 7-45 days prior to COVID-19 diagnosis with COVID-related hospitalization or death. Result(s): There were 340 maintenance dialysis patients with RBD s-Ab levels assessed at a median 23 [16,40] days prior to COVID diagnosis, with mean age 65+/-13 years, 51% female, 51% White, 91% HD and vintage 4.3+/-4.3 years. While COVID-19 diagnosis and COVID-related hospitalization or death events occurred across RBD s-Ab levels (Figure), 74 of 93 (80%) COVID-related hospitalizations and 24 of 25 deaths (96%) occurred at RBD s-Ab level <500 BAU/mL Conclusion(s): Maintenance dialysis patients are at risk for serious COVID events when RBD s-Ab < 500 BAU/mL. Routine RBD s-Ab measurement informing personalized vaccination strategies to keep titers above 500 BAU/mL may benefit this high-risk population.
ABSTRACT
Background: Preventing COVID-19 infection or its consequences through SARSCoV- 2 vaccination in maintenance dialysis patients, a high risk population, is imperative. We determined relative vaccine effectiveness (VE) of 1, 2, or 3 doses of an mRNA vaccine in preventing SARS-CoV-2 infection, hospitalization, and death. Method(s): All adult maintenance dialysis patients at Dialysis Clinic, Inc. offered an mRNA vaccine between 12/15/20 and 2/28/22 were included, with follow up time through 3/31/22. Using a multivariable logistic regression model, we calculated adjusted odds ratios (OR) for COVID-19 infection and associated hospitalization and death within 30 days during pre-Delta (12/15/20-6/19/21), Delta (6/20-12/18/21) and Omicron (12/19/21-2/28/22) periods. VE was calculated as (1-adjusted OR) x 100%. Patients were censored at infection, death, or transplantation. Result(s): The 17,309 maintenance dialysis patients included had mean age of 63+/-15 years, 58% male, 35% Black, 47% White, 87% HD and mean vintage 42+/-55 months. Across all three COVID-19 variant periods, VE increased with each successive mRNA dose received, improving protection against infection, hospitalization and death (Table). VE was highest among patients vaccinated with homologous mRNA-1273 regimens. Conclusion(s): Two or more SARS-CoV-2 mRNA vaccine doses exhibited VE protecting against COVID-19 related associated hospitalization and death in maintenance dialysis patients irrespective of variant era. At least 3 doses maximizes protection and may be necessary due to uremia-related mild to moderate immunodeficiency. (Table Presented).