Significance Statement
Because of multiple comorbidities and demographic characteristics, patients on dialysis are at high risk for COVID-19–related morbidity and mortality. However, such patients were not included in SARS-CoV-2 vaccine trials. To study the real-world effectiveness and immunogenicity of two mRNA SARS-CoV-2 vaccines (BNT162b2 and mRNA-1273) in a large, representative population of in-center hemodialysis patients in the United States, the authors conducted a retrospective, observational study to estimate these vaccines’ clinical effectiveness and ability to induce antibody responses. Their use was associated with a 73%–78% lower risk of COVID-19 infection and significantly lower risks of hospitalization or death. Nearly all vaccinated patients generated antibodies. These findings provide support for the use of these vaccines in patients on hemodialysis.
Keywords: end stage kidney disease, end-stage renal disease, ESRD, dialysis, coronavirus disease 2019, COVID-19, SARS-CoV-2, vaccine, BNT162 vaccine, RNA, messenger
Abstract
Background
Patients on hemodialysis have an elevated risk for COVID-19 but were not included in efficacy trials of SARS-CoV-2 vaccines.
Methods
We conducted a retrospective, observational study to estimate the real-world effectiveness and immunogenicity of two mRNA SARS-CoV-2 vaccines in a large, representative population of adult hemodialysis patients in the United States. In separate, parallel analyses, patients who began a vaccination series with BNT162b2 or mRNA-1273 in January and February 2021 were matched with unvaccinated patients and risk for outcomes were compared for days 1-21, 22-42, and ≥43 after first dose. In a subset of consented patients, blood samples were collected approximately 28 days after the second dose and anti–SARS-CoV-2 immunoglobulin G was measured.
Results
A total of 12,169 patients received the BNT162b2 vaccine (matched with 44,377 unvaccinated controls); 23,037 patients received the mRNA-1273 vaccine (matched with 63,243 unvaccinated controls). Compared with controls, vaccinated patients’ risk of being diagnosed with COVID-19 postvaccination became progressively lower during the study period (hazard ratio and 95% confidence interval for BNT162b2 was 0.21 [0.13, 0.35] and for mRNA-1273 was 0.27 [0.17, 0.42] for days ≥43). After a COVID-19 diagnosis, vaccinated patients were significantly less likely than unvaccinated patients to be hospitalized (for BNT162b2, 28.0% versus 43.4%; for mRNA-1273, 37.2% versus 45.6%) and significantly less likely to die (for BNT162b2, 4.0% versus 12.1%; for mRNA-1273, 5.6% versus 14.5%). Antibodies were detected in 98.1% (309/315) and 96.0% (308/321) of BNT162b2 and mRNA-1273 patients, respectively.
Conclusions
In patients on hemodialysis, vaccination with BNT162b2 or mRNA-1273 was associated with a lower risk of COVID-19 diagnosis and lower risk of hospitalization or death among those diagnosed with COVID-19. SARS-CoV-2 antibodies were detected in nearly all patients after vaccination. These findings support the use of these vaccines in this population.
During a global pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected hundreds of millions of people, and been implicated in at least 4 million deaths. In December 2020, the US Food and Drug Administration granted emergency use authorizations for two SARS-CoV-2 vaccines (BNT162b2 [Pfizer/BioNTech] and mRNA-1273 [Moderna]). Clinical trials performed in the general population estimated the efficacy of these vaccines to be 94%–95% in protecting against severe forms of coronavirus disease 2019 (COVID-19).1,2 The dialysis population is highly enriched for risk factors for severe manifestations of COVID-19, such as advanced age, multiple underlying comorbid conditions, residence in densely populated urban areas, and overrepresentation of persons of color.3,4 It is therefore not surprising that this population has borne a disproportionate burden of COVID-19–related morbidity and mortality.5,6 Despite their heightened risk, dialysis patients were not included in the SARS-CoV-2 vaccine trials. We therefore conducted this study to estimate the effectiveness and immunogenicity of BNT162b2 and mRNA-1273 among a large, representative, real-world hemodialysis patient population.
Methods
Effectiveness Analyses
This retrospective study included patients who were ≥18 years and receiving in-center hemodialysis at a dialysis organization in the United States between January 1 and February 25, 2021. According to 45 Code of Federal Regulations part 46 from the US Department of Health and Human Services, this study was exempt from institutional review board (IRB) or ethics committee approval. We adhered to the Declaration of Helsinki, and informed consent was not required. The study was deemed exempt by Quorum IRB (Seattle, WA). Data were derived from the dialysis organization’s electronic health records. Socioeconomic indicators were derived from the 2020 United States census and linked by zip code.7 All analyses were performed separately for BNT162b2 and mRNA-1273 vaccines using parallel methods.
Vaccinated patients were identified as those who received a first dose of BNT162b2 (and separately, mRNA-1273) between January 1 and February 25, 2021; the date of this dose was set as index date. During the study period, approximately one third of patient vaccinations occurred in dialysis facilities. For those patients who did not receive a vaccine in clinic, vaccine information was ascertained through verbal attestation and review of vaccine cards. In keeping with intention-to-treat principles, we did not require that patients receive a second dose to complete the series. For each vaccinated patient, we identified as potential controls all otherwise eligible patients who had not received any SARS-CoV-2 vaccine on or before the corresponding index date. To account for geotemporal variability in the intensity of the epidemic, vaccinated patients were exactly matched to eligible unvaccinated patients on index date and US state of residence. Furthermore, to promote balance on susceptibility factors, vaccinated patients and controls were also matched on the basis of prior COVID-19 diagnosis, propensity score based on age, diabetes status, sex, race, dialysis attendance on index date, and body mass index. Race was considered as Black, White, Hispanic, Asian, or other. Propensity scores were estimated using a logit model and applied using a caliper of 0.01. Unvaccinated patients were selected randomly, with replacement, using variable matching ratios (up to 1:4 for BNT162b2 and 1:3 for mRNA-1273); an excess number of unvaccinated patients was sought to ensure sufficient aggregate follow-up time among unvaccinated patients, recognizing that many would be censored for subsequent vaccine receipt. Covariate balance between matched vaccinated patients and unvaccinated patients was assessed using descriptive statistics (means, standard deviations, counts, and proportions) and quantified in terms of standardized differences; standardized differences exceeding ±10% indicate substantial imbalance.8
Patients were considered at risk beginning on the day after index date until the earliest of COVID-19 diagnosis, death, loss to follow-up, or on study end (April 30, 2021); unvaccinated patients were additionally censored at the time of having received any SARS-CoV-2 vaccination (such unvaccinated patients could subsequently re-enter the study as vaccine-exposed patients if otherwise eligible). The primary outcome was PCR-confirmed COVID-19 diagnosis. Clinical surveillance protocols implemented across the organization have been described elsewhere.9,10 Briefly, at the time of each clinic visit, all patients undergo a standardized COVID-19 screening. Patients who screen positive for COVID-19 symptoms, or who indicate a recent contact with COVID-19–infected individuals, undergo reflexive nasal PCR testing. Additional surveillance procedures are in place to identify COVID-19 diagnoses made at other sites of care (e.g., emergency departments, hospitals) and to confirm and document PCR test results from these sites. The average COVID-19 case rate among patients treated at the dialysis organization during this time was 0.12 infections per-patient per-year. The follow-up period was separated into three intervals based on a priori assumptions: days 1–21, 22–42, and ≥43, corresponding roughly to the interval between vaccine doses, the period after the second dose before presumed immunity, and the period of presumed immunity, respectively. This choice was subsequently validated by visual inspection of log hazards plots and Schoenfeld residual testing, which confirmed violation of the proportional hazards assumption across the totality of follow-up time (P<0.001), but no violation of proportionality within these three periods (P>0.05). Time-dependent hazard ratios (HRs) were estimated for each of the three follow-up intervals using a clustered variance estimator to account for matching. To account for possible informative censoring, we performed sensitivity analyses utilizing inverse probability of censoring weighting following the method of Robins and Hernán.11–18 Weights were estimated by a pooled logistic model in which censoring events were the dependent variable and predicted on the basis of exposure status, age, female sex, race, prior COVID-19 history, Charlson comorbidity index score, diabetes, body mass index, community poverty level, community unemployment rates, community housing vacancy rates, and community high school graduate rates. Weights were applied to Cox proportional hazard models using the weight option in the Survival package for R.19 Confidence intervals (CIs) were estimated by bootstrap utilizing 200 number of replicates using the Boot package for R.20
We also compared hospitalization and mortality among vaccinated and unvaccinated patients who were diagnosed with COVID-19 during follow-up. Hospitalizations were defined as admissions of any cause that occurred during the 7 days before and 21 days after a COVID-19 diagnosis. This window was chosen to allow the capture of the following scenarios: (1) a symptomatic patient was diagnosed with COVID-19 and hospitalized soon thereafter; (2) a patient was diagnosed with COVID-19 and hospitalized later due to worsening of initially mild/moderate disease; (3) a patient was hospitalized for COVID-19–related symptoms, but an official COVID-19 diagnosis occurred after an initial false negative test; and (4) a patient was hospitalized for unrelated reasons and COVID-19 was incidentally detected during the admission. Mortality events were defined as any death that occurred after a COVID-19 diagnosis without a documented recovery from COVID-19, as defined by Centers for Disease Control and Prevention guidelines.21 Adjusted odds ratios for hospitalization and mortality were estimated using logit models adjusted for all covariates included in the matching algorithm.
Separately, we compared all-cause mortality between matched vaccinated and unvaccinated patients using Kaplan–Meier methods. All analyses were performed using R version 4.022; matching was performed using MatchIt23; standardized differences were calculated with Survey and TableOne24,25; HRs were calculated using Survival19; and boot strapping was performed using Boot.20
Immunogenicity Analysis
To estimate immunogenicity, we conducted a prospective study among a subset of patients who completed a BNT1612b2 or mRNA-1273 vaccination series. This study was reviewed and approved by Advarra IRB (Protocol # DCR 21-S-0016–00; approved on March 19, 2021). Eligible participants were patients who had received two doses of either BNT1612b2 or mRNA-1273 at a dialysis clinic run by the organization between January 15 and March 25, 2021. After patients provided written informed consent, a blood sample was collected 28–56 days after the second vaccine dose to measure anti–SARS-CoV-2 antibodies. Blood samples were collected before a dialysis treatment in a 5-ml serum separation tube, clotted for 30 minutes, centrifuged, and refrigerated before shipment. All samples were processed at a centralized, accredited laboratory (DaVita Labs). IgG was measured using an indirect chemiluminescence immunoassay for anti–SARS-CoV-2 IgG antibodies (Diazyme Laboratories), which detects antibodies against the SARS-CoV-2 spike and nucleocapsid proteins. IgM was not measured based on pilot data and previous experience, which indicated that measured IgM response was implausibly low in this population (e.g., <20% positive even in the 28-day period after documented SARS-CoV-2 infection, a time when IgM response should be high). Per the manufacturer’s recommendation, samples were scored IgG positive if the corresponding test reading was >1 arbitrary U/ml, and negative otherwise. We previously used this assay for research purposes due to its selectivity for SARS-CoV-2 antibodies and low levels of cross-reactivity to other coronaviruses or influenza viruses.9,10
Results
BNT162b2 Effectiveness
During the study period, 12,169 patients received at least one dose of BNT162b2 and were matched to 44,377 unvaccinated patients. In the matched sample, mean age was 69 years, 31.2% were Black, 16.3% were Hispanic, and 9.4% had prior history of COVID-19; these and other clinical characteristics were well balanced between vaccinated and unvaccinated patients (Figure 1A, Supplemental Table 1); census tract data indicate balance of socioeconomic indictors between vaccinated and unvaccinated patients as well (Supplemental Table 2). Among patients with a documented first BNT162b2 dose during the study period, 95.7% went on to receive the second dose. For patients who received a second dose, the median and interquartile range (IQR) time between doses was 21 (21–22) days.
Figure 1.
Baseline comparison of demographic characteristics. (A) Comparison of patients vaccinated with BNT162b2 versus matched unvaccinated patients and (B) comparison of patients vaccinated with mRNA-1273 versus matched unvaccinated patients.
Median and IQR follow-up time was 82 (73–94) days for BNT162b2 patients and 36 (16–66) days for unvaccinated patients, reflecting censoring of the latter due to subsequent vaccine receipt. Nonetheless, cumulative follow-up time remained greater for unvaccinated patients (5721 versus 2861 patient-years) given the intentional oversampling of controls. During the study period, 278 (2.3%) patients vaccinated with BNT162b2 and 913 (2.1%) unvaccinated patients were lost to follow-up.
During follow-up, there were 189 COVID-19 diagnoses among patients vaccinated (54 of which occurred on or after day 43) with BNT162b2 and 846 COVID-19 diagnoses among unvaccinated patients. Kaplan–Meier curves for COVID-19–free survival for patients vaccinated with BNT162b2 and unvaccinated patients are shown in Figure 2A. The HRs were 0.83 (95% CI, 0.68 to 1.03), 0.61 (95% CI, 0.40 to 0.93), and 0.22 (95% CI, 0.13 to 0.35) during 1–21, 22–42, and ≥43 days after the first dose of BNT162b2, respectively (Figure 2B). Results were nearly identical in inverse probability of censoring weighted sensitivity analyses: HRs were 0.84 (95% CI, 0.61 to 1.00), 0.59 (95% CI, 0.37 to 0.97), and 0.21 (95% CI, 0.07 to 0.32) 1–21, 22–42, and ≥43 days after the first dose of BNT162b2, respectively. Furthermore, results were similar in two additional sensitivity analyses: (1) in patients who did not have a history of COVID-19 before vaccination (Supplemental Figure 1); and (2) in unvaccinated patients who were not allowed to re-enter the study upon receipt of BNT162b2 (Supplemental Figure 2). Effect estimates for BNT162b2 in the period day 43+ were similar when consideration was limited to patients who went on to complete the vaccine series versus their matched unvaccinated patients.
Figure 2.
COVID-19 diagnoses among patients who received BNT162b2 and matched unvaccinated patients. (A) Kaplan–Meier curves representing infection-free survival. Arrow corresponds to manufacturer’s recommended 21-day time point for administration of second dose of BNT162b2. The median (IQR) time between doses in the study population was 21 (21–22) days. (B) Hazard ratios (95% CIs) during follow-up days 1–21, 22–42, and ≥ 43.
Among BNT162b2 patients who were diagnosed with COVID-19 during follow-up, 28.0% (95% CI, 22.1% to 34.8%) were hospitalized in the period surrounding COVID-19 diagnosis compared with 43.4% (95% CI, 40.1% to 46.7%) of unvaccinated patients diagnosed with COVID-19; the adjusted odds ratio for hospitalization among COVID-19 diagnosed patients was 0.50 (95% CI, 0.35 to 0.70; P<0.001). Among BNT162b2 patients who were diagnosed with COVID-19 during follow-up, 4.2% (95% CI, 2.2% to 8.1%) subsequently died compared with 12.1% (95% CI, 10.0% to 14.4%) of unvaccinated patients diagnosed with COVID-19; the adjusted odds ratio for mortality among COVID-19 diagnosed patients was 0.29 (95% CI, 0.13 to 0.58; P<0.001). All-cause mortality was lower among vaccinated patients versus unvaccinated patients (log rank P<0.001; Figure 4A). During follow-up, 260 of 12,169 BNT162b2 patients died and 1258 of 44,377 matched unvaccinated patients died. At day 120, Kaplan–Meier survival cumulative incidence was 0.031 (95% CI, 0.026 to 0.036) versus 0.071 (95% CI, 0.064 to 0.077).
Figure 4.
All-cause mortality during follow-up. (A) Among patients who received BNT162b2 and matched unvaccinated patients and (B) among patients who received mRNA-1273 and matched unvaccinated controls.
mRNA-1273 Effectiveness
During the study period, 23,037 patients received at least one dose of mRNA-1273 and were matched to 64,243 unvaccinated patients. In the matched sample, mean age was 68 years, 26.2% were Black, 23.6% were Hispanic, and 8.0% had prior history of COVID-19; these and other clinical characteristics were well balanced between vaccinated and unvaccinated patients (Figure 1B, Supplemental Table 3); census tract data indicate balance of socioeconomic indictors between vaccinated and unvaccinated patients as well (Supplemental Table 4). Among patients with a documented first dose of mRNA-1273 during the study period, 95.4% went on to receive a documented second dose. For patients who received a second dose, the median and IQR time between doses was 28 (28–29) days.
Median and IQR follow-up time was 86 (76–99) days for mRNA-1273 patients and 44 (22–70) days for unvaccinated patients, reflecting censoring of the latter due to subsequent vaccine receipt. Nonetheless, cumulative follow-up time remained greater for unvaccinated patients (7391 versus 5232 patient-years) given the intentional oversampling of controls. During the study period, 384 (1.7%) of patients vaccinated with mRNA-1273 and 999 (1.6%) of unvaccinated patients were lost to follow-up.
During follow-up, there were 266 COVID-19 diagnoses among patients vaccinated with mRNA-1273 (28 of which occurred on or after day 43) and 740 COVID-19 diagnoses among unvaccinated patients. Kaplan–Meier curves for COVID-19–free survival for patients vaccinated with mRNA-1273 and unvaccinated patients are shown in Figure 3A. The HRs were 0.96 (95% CI, 0.79 to 1.16), 0.51 (95% CI, 0.34 to 0.75), and 0.27 (95% CI, 0.17 to 0.42) during 1–21, 22–42, and ≥43 days after the first dose of mRNA-1273, respectively (Figure 3B). Results were nearly identical in inverse probability of censoring weighted sensitivity analyses: HRs were 0.96 (95% CI, 0.68 to 1.08), 0.50 (95% CI, 0.30 to 0.81), and 0.26 (95% CI, 0.12 to 0.43) 1–21, 22–42, and ≥43 days after the first dose of mRNA-1273, respectively. Furthermore, results were similar in two additional sensitivity analyses: (1) in patients who did not have a history of COVID-19 before vaccination (Supplemental Figure 3); and (2) in unvaccinated patients who were not allowed to re-enter the study upon receipt of mRNA-1273 (Supplemental Figure 4). Effect estimates for mRNA-1273 in the period day 43+ were similar when consideration was limited to patients who went on to complete the vaccine series versus their matched unvaccinated patients.
Figure 3.
COVID-19 diagnoses among patients who received mRNA-1273 and matched unvaccinated patients. (A) Kaplan–Meier curves representing infection-free survival. Arrow corresponds to manufacturer’s recommended 28-day time point for administration of second dose of mRNA-1273. The median (IQR) time between doses in the study population was 28 (28–29) days. (B) Hazard ratios (95% CIs) during follow-up days 1–21, 22–42, and ≥43.
Among mRNA-1273 patients who were diagnosed with COVID-19 during follow-up, 37.2% (95% CI, 31.6% to 43.2%) were hospitalized in the period surrounding COVID-19 diagnosis compared with 45.6% (95% CI, 42.0% to 49.1%) of unvaccinated patients diagnosed with COVID-19; the adjusted odds ratio for hospitalization among COVID-19 diagnosed patients was 0.68 (95% CI, 0.51 to 0.91; P<0.001). Among mRNA-1273 patients who were diagnosed with COVID-19 during follow-up, 5.6% (95% CI, 3.4% to 9.1%) subsequently died compared with 14.5% (95% CI, 11.7% to 16.7%) of unvaccinated patients diagnosed with COVID-19; the adjusted odds ratio for mortality among COVID-19 diagnosed patients was 0.35 (95% CI, 0.19 to 0.58; P<0.001). All-cause mortality was lower among vaccinated patients versus unvaccinated patients (log rank P<0.001; Figure 4B). During follow-up, 486 of 23,037 mRNA-1273 patients died and 1529 of 63,234 matched unvaccinated patients died. At day 120, Kaplan–Meier survival cumulative incidence was 0.028 (95% CI, 0.024 to 0.032) versus 0.068 (95% CI, 0.059 to 0.076).
Immunogenicity
We measured antibodies in 315 and 321 patients who had completed a two-dose series of BNT162b2 and mRNA-1273, respectively. Median (IQR) of time from second dose to blood sampling was 34 (31–40) days for BNT162b2 and 45 (43–48) days for mRNA-1273. Figure 5 shows the proportion of patients who were IgG positive. Among BNT162b2-vaccinated patients, 98.1% (95% CI, 95.9% to 99.3%) had anti–SARS-CoV-2 IgG antibodies. Among mRNA-1273–vaccinated patients, 96.0% (95% CI, 93.6% to 98.1%) had anti–SARS-CoV-2 IgG antibodies.
Figure 5.
Proportion of fully vaccinated patients with evidence of anti–SARS-CoV-2 IgG.
Discussion
In this study, we found that both BNT162b2 and mRNA-1273 were associated with a high degree of protection against COVID-19 in a large, representative, real-world cohort of hemodialysis patients. Furthermore, we found that the vast majority of hemodialysis patients who received a two-dose course of BNT162b2 or mRNA-1273 mounted a detectable IgG antibody response to SARS-CoV-2.
In the effectiveness analyses, we were primarily interested in the time period ≥43 days after the first dose of vaccine (i.e., when sufficient time had passed for immunity to have developed). We observed that receipt of BNT162b2 and mRNA-1273 was associated with a 78% and 73% lower relative risk of disease, respectively. These estimates are lower than efficacy estimates from clinical trials.1,2 However, our estimates are in line with reported real-world effectiveness estimates from several large studies of nondialysis patients,26–31 which is reassuring given that dialysis patients are, on average, older and sicker than other populations studied. Furthermore, these vaccine effectiveness estimates are nearly identical in magnitude to those observed among dialysis patients having had a prior COVID-19 diagnosis (i.e., naturally acquired immunity).9 Furthermore, our results also indicate that breakthrough instances of COVID-19 after BNT162b2 or mRNA-1273 were associated with lower risks of hospitalization and death.
We also estimated vaccine effectiveness earlier in the postvaccine course, because such data might aid in clinical decision making with regard to vaccine schedules. In the 21 days immediately after receipt of a first vaccine dose, both BNT162b2 and mRNA-1273 were estimated to be minimally effective (16% and 4%, respectively, with CIs crossing zero). Between days 22 and 42, during which patients would likely have received a second vaccine dose, we estimated effectiveness to be 39% and 49% for BNT162b2 and mRNA-1273, respectively. These findings support the importance of completing the full vaccine schedule, particularly in high-risk patients.
Poor humoral immune response to other vaccines has been well documented among dialysis patients.32–34 To estimate the humoral immune response to these vaccines, we quantified the proportion of patients who were seropositive for anti–SARS-CoV-2 IgG after two doses of BNT162b2 or mRNA-1273. We found that nearly all (96%–98%) hemodialysis patients who completed the full vaccination series were IgG-seropositive. Magnitude of response was not considered because the assay used was semiquantitative.
There are limitations associated with this study. As with any observational study, there is the possibility of residual confounding and bias (e.g., misclassification of exposure status for patients reporting vaccinations outside of the clinic; potential for healthy user bias for patients who received the vaccine versus those who did not). Limited follow-up time did not allow estimation of the durability of vaccine response. The electronic health records do not contain standardized documentation of COVID-19 severity; therefore, we could not estimate effectiveness with regard to severity of illness. Because individual vaccines were distributed differentially in time and space, direct head-to-head comparison of these vaccines was not possible. Although vaccinated and unvaccinated patients were matched at the state level, it is possible that differences in COVID-19 case rates across regions within a state could have confounded results. Finally, we could not estimate the effectiveness against specific SARS-CoV-2 variants or against asymptomatic infections.
In summary, our results demonstrate that, in the dialysis setting, two widely available and commonly used SARS-CoV-2 vaccines are associated with a lower risk of COVID-19 diagnosis and a lower risk of hospitalization or death among patients diagnosed with COVID-19. Moreover, the vast majority of hemodialysis patients should be expected to mount an immune response after completing a BNT162b2 or mRNA-1273 vaccination series. Our results support the use of these vaccines in hemodialysis patients.35,36
Disclosures
S. Brunelli, J. Connaire, T. Kelley, J. Luo, K. McKeon, S. Sibbel, F. Tentori, A. Walker, K. Wendt, and A. Young and are employees of DaVita Clinical Research. R. Lazar and M. Zywno are employees of DaVita, Inc. S. Brunelli’s spouse is an employee of AstraZeneca. J. Connaire reports consultancy agreements with Diality, Dynavax, GlaxoSmithKline, Relypsa, and Sanifit; reports ownership interest with DaVita, Inc.; reports research funding with Akebia, Ardelyx, AstraZeneca, Chinook, GlaxoSmithKline, Goldfinch Bio, Merck, Otsuka, Sanifit, Sera Trials, and Travere; and reports scientific advisor or membership with GlaxoSmithKline and Sanifit. T. Kelley reports ownership interest with DaVita, Inc. J. Luo reports ownership interest with DaVita, Inc. K. McKeon reports ownership interest with Aphria, Catalyst Pharmaceuticals, Chewy, Corbus Pharmaceuticals, General Electric, Inovio, and Southwest Airlines. S. Sibbel reports ownership interest with DaVita, Inc. F. Tentori reports scientific advisor or membership with Ardelyx Medical Advisory Board. A. Walker reports ownership interest with DaVita, Inc. A. Young reports ownership interest with DaVita, Inc.; and reports other interests/relationships as board member of Kidney Health Initiative.
Funding
None.
Supplementary Material
Acknowledgments
Dr. Scott Sibbel, Ms. Katherine McKeon, Dr. Jiacong Luo, Dr. Jeffrey J. Connaire, Dr. Francesca Tentori, Ms. Amy Young, and Dr. Steven M. Brunelli designed the study; Ms. Tara Kelley, Dr. Jeffrey J. Connaire, Dr. Francesca Tentori, Ms. Amy Young, and Dr. Steven M. Brunelli provided clinical/logistical leadership and oversight; Mr. Karl Wendt, Ms. Rachael Lazar, and Ms. Meredith L. Zywno prepared the analytic data files; Dr. Scott Sibbel, Ms. Katherine McKeon, and Dr. Jiacong Luo performed the analysis; Dr. Scott Sibbel, Ms. Katherine McKeon, Dr. Jiacong Luo, Dr. Adam G. Walker, Dr. Francesca Tentori, and Dr. Steven M. Brunelli interpreted the findings; Dr. Adam G. Walker, Dr. Scott Sibbel, Dr. Steven M. Brunelli, and Dr. Francesca Tentori drafted the manuscript; and all authors reviewed and approved the manuscript before submission.. The authors would like to thank the patients and staff of DaVita, Inc., without whom this research would not have been possible.
Footnotes
Published online ahead of print. Publication date available at www.jasn.org.
Supplemental Material
This article contains the following supplemental material online at http://jasn.asnjournals.org/lookup/suppl/doi:10.1681/ASN.2021060778/-/DCSupplemental.
Supplemental Figure 1. COVID-19 diagnoses among patients who received BNT162b2 and matched unvaccinated patients without history of prior COVID-19.
Supplemental Figure 2. COVID-19 diagnoses among patients who received BNT162b2 and matched unvaccinated patients: sensitivity analysis restricting re-entry of unvaccinated patients.
Supplemental Figure 3. COVID-19 diagnoses among patients who received mRNA-1273 and unvaccinated patients without history of prior COVID-19.
Supplemental Figure 4. COVID-19 diagnoses among patients who received mRNA-1273 and matched unvaccinated patients: sensitivity analysis restricting re-entry of unvaccinated patients.
Supplemental Table 1. Baseline comparison of matched BNT162b2 patients and unvaccinated patients by match ratio. In all instances, index date and US state of residence were perfectly balanced (not shown).
Supplemental Table 2. Comparison of measures of socioeconomic status of matched BNT162b2 and unvaccinated patients by match ratio.
Supplemental Table 3. Baseline comparison of matched mRNA-1273 patients and unvaccinated patients by match ratio. In all instances, index date and US state of residence were perfectly balanced (not shown).
Supplemental Table 4. Comparison of measures of socioeconomic status of matched mRNA-1273 and unvaccinated patients by match ratio.
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