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).
ABSTRACT
Background: Among patients receiving maintenance dialysis, seroresponse to an initial vaccine series wanes over time. Previously, we showed that additional doses elicit a substantial short-term increase in seroresponse. Here, we assess seroresponse over time in a national sample of maintenance dialysis patients. Method(s): Using retrospective clinical data, we assessed seroresponse to additional SARS-CoV-2 vaccine doses over time among maintenance dialysis patients cared for at Dialysis Clinic, Inc (DCI) facilities. Via a clinical protocol available to dialysis providers, antibodies against SARS-CoV-2 spike antigen were assessed monthly alongside routine labwork. Patients with history of COVID-19 prior to additional dose and patients who received Janssen vaccine as an additional dose were excluded. Titers after a second additional dose (i.e., for most, a fourth dose) or after COVID-19 diagnosis were excluded from analysis. Result(s): Among 1707 patients who had received an additional vaccine dose and had at least one titer level measured after the additional dose, more than 75% had a titer level at the upper limit of the assay in the first month after the additional dose. Titer levels then waned across vaccine types. By Month 6, median [IQR] titer was 68.37 [22.30, >=100] among Moderna recipients, 59.94 [39.90, 79.97] among Moderna half-dose recipients, and 71.29 [22.46, >=100] among Pfizer recipients. Conclusion(s): Among patients receiving maintenance dialysis, anti-spike IgG levels after an additional SARS-CoV-2 vaccine dose wane over time across vaccine types. These results suggest a role for routine antibody monitoring to assess possible need for further re-dosing.
ABSTRACT
Background: Durability of SARS-CoV-2 receptor-binding domain spike antibody (RBD s-Ab) levels among patients receiving dialysis after COVID-19 [WDE1] is unknown[EL2] beyond 6 months. We describe the persistence (index value ≥ 1 and ≥ 2 U/L) of semi-quantitative RBD s-Ab levels in dialysis patients over 14 month period. Methods: All maintenance dialysis patients (≥18 years old) within Dialysis Clinic, Inc. 260 clinics in 28 states with COVID-19 infection history and RBD s-Ab levels determined between Jan 1 and May 23, 2021 were included. On the day of RBD s-Ab level determination, patient demographics (age, sex, race, modality, ESKD vintage) and days since COVID-19 diagnosis were determined. Patient RBD s-Ab levels obtained after COVID-19 vaccination were excluded. Results: A total of 515 patients, mean age 62±14 years, 57% male, 46% White, 94% HD and vintage 4.6±4.4 years[EL1], [HJM2] had 835 RBD s-Ab levels assessed at a median of 59 days (range 0-422 days) post COVID-19 diagnosis. RBD s-Ab levels were assessed 1, 2 or ≥3 times in 64%, 18% and 18% patients, respectively. Only 32 (6.2%) patients had undetectable RBD s-Ab on the last draw. A cross sectional summary of the last available RBD s-Ab levels suggests that titers remain detectable for long duration (Figure[EL3] [HJM4]). In patients (N=186;36%) with multiple RBD s-Ab levels (mean 28±15;median 28 days between levels), subsequent values were higher, lower [EL5] [HJM6] or unchanged 7%, 16% and 77% of time[EL7], respectively. Conclusions: Most maintenance dialysis patients sampled developed SARS-CoV-2 RBD s-Ab after COVID diagnosis, and durability extends up to 14 months. Further elucidation of longitudinal RBD s-Ab values post-COVID-19 infection as well as after completing vaccination for SARS-CoV-2 is needed.
ABSTRACT
Background: Vaccines against SARS-CoV-2 are highly effective in the general population;however, their efficacy may be diminished in maintenance dialysis patients, a population particularly vulnerable to COVID-19. We assessed vaccine response in a national sample of maintenance dialysis patients. Methods: Using retrospective clinical data, we assessed seroresponse to vaccine among maintenance dialysis patients cared for at 130 Dialysis Clinic, Inc (DCI) facilities. Via a clinical protocol available to early vaccinating facilities, antibodies against SARSCoV-2 spike antigen were semi-quantitatively assessed beginning with the monthly blood draw at least two weeks after completion of a SARS-CoV-2 vaccine series. Vaccine response was defined as a titer ≥2 U/L, and logistic regression analysis was used to identify characteristics associated with response. Patients with history of COVID-19 prior to antibody assessment were excluded. Results: Among 1,352 patients, 996 (74%) had a serologic response. Serologic response differed significantly by vaccine type: 314/386 (81%) among BNT162b2/ Pfizer recipients, 615/655 (94%) among mRNA-1273/Moderna recipients, and 67/311 (22%) among Ad26.COV2.S/Janssen recipients. Age greater than 75, lack of hepatitis B immunity, immune-modulating medication, lower serum albumin, and COPD were associated with vaccine non-response (Figure). Conclusions: Serologic response to mRNA vaccines is robust among chronic dialysis patients, and the use of mRNA vaccines should be promoted aggressively in this vulnerable population. High rates of non-response to the Janssen vaccine warrant further study. Future research should evaluate the potential role for boosters and whether seroresponse corresponds with protection from COVID-19.
ABSTRACT
Background: The CDC recommends screening of all patients for COVID exposure history and or signs and symptoms prior to treatment. In order to limit the spread of COVID within our facilities, Dialysis Clinic Inc. screens all patients prior their in-center hemodialysis treatment or peritoneal dialysis visit consistent with recommendations. Methods: We describe the outpatient screening results of our dialysis patients having a positive screen as patients under investigation (PUI) to activate local protocols for isolation and testing. We determined the frequencies of positive screening parameters and rate of identifying COVID patients. Results: From 2/17 to 5/1, 2020, facilities screened 15,602 patients over 402,002 in-person visits, identifying 959 PUI's (6%). Among PUIs, 61 of 351 (17%) COVID+ patients were correctly triaged prior to COVID+ diagnosis. In the subset of 788 PUIs screened prior to 4/11/20 where we were able to catalogue reasons for positive screening, 149 (19%) had exposure only and 639 exhibited symptoms (81%), of which 15 had exposure;34 resided in group home (GH) and 7 had both exposure and GH residence. It was determined 41 (6.4%) were COVID+. Frequency of symptoms elicited by PUI are shown below. Conclusions: 959 PUIs were identified and isolated by our screening process, resulting in the successful preemptive triage of 61 COVID+ (6%) patients before testing positive, potentially limiting infection spread in the facility. Cough and fever were the most common reasons for positive screen, and fever was most commonly associated with COVID+ diagnosis. However, the majority (83%) of COVID+ patients were primarily asymptomatic and hence not captured by screening. (Table Presented).
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Background: The SARS-COV-2 pandemic (COVID) impacted ESRD patients on dialysis, categorized by the CDC as immunocompromised. We describe the characteristics and outcomes in patients treated by a non-profit dialysis provider. Methods: From 2/17 to 5/29, 2020, Dialysis Clinic Inc. had identified 422 COVID+ patients from 90 clinics in 20 states. We compared their characteristics relative to the uninfected source clinic population (N=6,993) and tracked outcomes over the 15-week period. Results: Comparative characteristics are shown in the table (∗p<0.05). Hospitalization occurred in 295 (70%) with 75 deaths, 159 discharges and 61 still hospitalized. Ten patients died <30 days post-discharge. Another 11 deaths occurred in 116 non-hospitalized patients. Overall, 96 of 422 died (22.7%). While more black patients were infected, death rates were higher in white than black dialysis patients (31.5% vs. 18.8%, p=0.008). Conclusions: Chronic dialysis patients with COVID have higher death rates than the general population. Infected patients tended to be older, with more comorbidity, particularly DM/CVD, and utilized respiratory inhalers/assistance. Group home residents were overrepresented with COVID while home dialysis patients were disproportionately spared.
ABSTRACT
Background: From 2/17 to 5/29, 2020, Dialysis Clinic Inc. had 422 maintenance dialysis patients diagnosed with COVID from 90 clinics in 20 states. While prognostic factors in the general population have been reported, there is limited information regarding the US dialysis population. Methods: Over a 15 week period of observation, 96 patients died (22.7%) and 116 (27.5%) were not hospitalized (for up to 30 days post-COVID diagnosis), likely with milder illness. We compiled univariable associations with p<0.1 into stepwise logistic regression models (forcing in age, sex. race) to determine factors associated with 1) Death from COVID;and 2) Moderate/severe illness (hospitalized or died without hospitalization <30 days post-COVID diagnosis). Results: Candidate variables are listed in the table, with retained significant factors marked (a or b at p<0.05). Notably, 42% of all deaths occurred at age >;75 years, increasing to 74% of all deaths at age >;65 years. Wheelchair use also associated with higher death risk. Conclusions: Dialysis patients with low albumin and vintage ≧1 year associated with increased illness severity. It was surprising that a history of pneumonia vaccine associated with more severe illness - whether this reflects 'treatment by indication' bias vs. pulmonary immune activation by vaccination vs. chance finding is unclear. PVD also tended to increase illness severity but more importantly, was significantly associated with risk of death, independent of older age.