ABSTRACT
Given the increased morbidity and mortality from COVID-19 among patients undergoing maintenance dialysis, we examined the seroresponse to an additional dose of SARS-CoV-2 mRNA vaccine, using a hypothesized protective anti-spike protein IgG antibody threshold of 7 based on prior work. Among 395 patients, 384 (97%) had seroresponse [≥]7 following administration of the third dose. Among those with suboptimal (peak <7) and minimal (peak <1) seroresponse to an initial mRNA vaccine regimen, the rate of seroresponse [≥]7 following a third dose was 97% (36 of 37) and 64% (14 of 22), respectively. Given ongoing high rates of COVID-19 and rapidly waning immunity after an initial vaccine series, we recommend a third mRNA vaccine dose be standard for all patients receiving maintenance dialysis.
ABSTRACT
BackgroundSARS-CoV-2 vaccine effectiveness during the Delta period and immunogenicity threshold associated with protection against COVID-19 related hospitalization or death in the dialysis population is unknown. MethodsA retrospective, observational study assessed SARS-CoV-2 vaccine effectiveness and immunogenicity threshold in all adult maintenance dialysis patients without COVID-19 history treated between February 1 and October 2, 2021. All COVID-19 infections, composite of hospitalization or death following COVID-19 and available SARS-CoV-2 anti-spike immunoglobulin (Ig) G values were extracted from electronic medical record. COVID-19 cases per 10,000 days at risk and vaccine effectiveness during pre-Delta and Delta periods were determined. ResultsOf 15,718 patients receiving dialysis during the study period, 11,191 (71%) were fully vaccinated, 733 (5%) were partially vaccinated and 3,794 (24%) were unvaccinated. 967 COVID-19 were cases identified: 511 (53%) occurred in unvaccinated patients and 579 (60%) occurred during the Delta period. COVID-19 related hospitalization or death was less likely among vaccinated versus unvaccinated patients for all vaccines (adjusted HR 0.19 [0.12, 0.30]) and for BNT162b2/Pfizer, mRNA-1273/Moderna, and Ad26.COV2.S/Janssen (adjusted HR=0.25 [0.16, 0.40], 0.14 [0.08, 0.22], and 0.34 [0.17, 0.68] respectively). Among those with anti-spike IgG levels, those with IgG level [≥] 7 had significantly lower risk of a COVID-19 diagnosis (HR=0.25 [0.15, 0.42]) and none experienced a COVID-related hospitalization or death. ConclusionsAmong maintenance dialysis patients, SARS-CoV-2 vaccination was associated with a lower risk of COVID-19 diagnosis and associated hospitalization or death. Among vaccinated patients, low anti-spike IgG level is associated with worse COVID-19 related outcomes. Significance StatementSARS-CoV-2 vaccine effectiveness and association between antibody levels and clinical outcomes in maintenance dialysis patients is not known. Between February 1 and October 2, 2021, vaccine effectiveness was 85% against COVID-19 infection and 81% against composite of COVID-related hospitalization or death. COVID-19 case rates and severe outcomes were higher during the Delta dominant period (June 27-October 2, 2021). Increasing time (weeks) since full vaccination status was associated with increased risk for COVID-19 related hospitalization or death. Anti-spike IgG level [≥] 7 had lower risk of a COVID-19 diagnosis and no COVID-related hospitalization or death. Our findings supports utilization of SARS-CoV-2 vaccination and suggests that monitoring SARS-CoV-2 antibody levels and administering additional vaccine doses to maintain adequate immunity will be beneficial.
ABSTRACT
Among patients receiving maintenance dialysis with a national US dialysis provider, fully vaccinated dialysis patients were significantly less likely to be diagnosed with COVID-19 or be hospitalized than unvaccinated patients. Ad26.COV2.S/Janssen vaccine had significantly worse outcomes, and mRNA-1273/Moderna the best. Among the 27 patients with breakthrough COVID-19 and anti-spike IgG antibodies measured, 23/27 (85%) breakthrough COVID-19 cases occurred at titers <2 U/L (lower limit of a positive response); 14 of these patients never developing Ab titers above 2 U/L. Only 3/27 were receiving immunosuppression. The potential use of antibody titers to guide vaccinations should be explored.
ABSTRACT
Background and ObjectivesWhile most maintenance dialysis patients exhibit initial seroresponse to vaccination, concerns remain regarding the durability of this antibody response. This study evaluated immunity over time. Design, setting, participants, and measurementsThis retrospective cohort study included maintenance dialysis patients from a midsize national dialysis provider who received a complete SARS-CoV-2 vaccine series and had at least one antibody titer checked after full vaccination. Immunoglobulin G spike antibodies (SAb-IgG) titers were assessed monthly with routine labs beginning after full vaccination and followed over time; the semiquantitative SAb-IgG titer reported a range between 0 and [≥] 20 U/L. Descriptive analyses compared trends over time by prior history of COVID-19 and type of vaccine received. Time-to-event analyses were conducted for the outcome of loss of seroresponse (SAb-IgG < 1 U/L or development of COVID-19). Cox proportional hazards regression was used to adjust for additional clinical characteristics of interest. ResultsAmong 1898 maintenance dialysis patients, 1567 (84%) had no prior history of COVID-19. Patients without a history of COVID-19 had declining titers over time. Among 441 BNT162b2/Pfizer recipients, median [IQR] SAb-IgG titer declined from 20 [5.99-20] U/L in month 1 to 1.30 [0.15-3.59] U/L by month 6. Among 779 mRNA-1273/Moderna recipients, median [IQR] SAb-IgG titer declined from 20 [20-20] in month 1 to 6.20 [1.74-20] by month 6. The 347 Ad26.COV2.S/Janssen recipients had a lower titer response than mRNA vaccine recipients over all time periods. In time-to-event analyses, Ad26.COV2.S/Janssen and mRNA-1273/Moderna recipients had the shortest and longest time to loss of seroresponse, respectively. The maximum titer reached in the first two months after full vaccination was predictive of the durability of the SAb-IgG seroresponse; patients with SAb-IgG titer 1-19.99 U/L were more likely to have loss of seroresponse compared to patients with SAb-IgG titer [≥] 20 U/L (HR 23.9 [95% CI: 16.1-35.5]). ConclusionsVaccine-induced seroresponse wanes over time among maintenance dialysis patients across vaccine types. Early titers after full vaccination predict the durability of seroresponse.
ABSTRACT
ImportanceVaccines 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 infection and morbidity. ObjectiveWe assessed vaccine response in a national sample of maintenance dialysis patients and identified predictors of response. DesignRetrospective cohort study Setting130 Dialysis Clinic, Inc (DCI) facilities ParticipantsMaintenance dialysis patients without known prior COVID-19 or a positive baseline antibody titer Exposure(s)Vaccine type and clinical characteristics Main Outcome(s)Using a semi-quantitative assay for antibodies against SARS-CoV-2 spike antigen, vaccine response was defined as at least one titer [≥]1 U/L between 14 and 74 days after completion of a SARS-CoV-2 vaccine series. Regression analysis was used to identify characteristics associated with response. ResultsAmong 1528 patients, 437 received BNT162b2/Pfizer vaccine, 766 received mRNA-1273/Moderna, and 325 received Ad26.COV2.S/Janssen. Serologic response differed significantly by vaccine type: 381/437 (87%) among BNT162b2/Pfizer recipients, 736/766 (96%) among mRNA-1273/Moderna recipients, and 119/325 (37%) among Ad26.COV2.S/Janssen recipients. Vaccine type, older age, immune-modulating medication, history of transplantation, and lower serum albumin were associated with vaccine non-response. Conclusions and RelevanceSerologic response to mRNA vaccines is robust among maintenance dialysis patients. Future research should evaluate durability of this response, correlation between seroresponse and protection from COVID-19, and the role of the AD26.COV2.S/Janssen vaccine in this vulnerable population.
