Antibody response to mRNA SARS-CoV-2 vaccines in haemodialysis patients

Abstract

Background: Some studies have shown an attenuated immune response in haemodialysis patients after vaccination. The present study examines the humoral response after mRNA vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a large population of haemodialysis patients from different outpatient dialysis centres.

Methods: We retrospectively assessed antibodies against SARS-CoV-2 spike protein and nucleocapsid protein (chemiluminescence immunoassays, Roche diagnostics) 3-6 weeks after the second mRNA vaccine dose in 179 maintenance haemodialysis and 70 non-dialysis patients (control cohort). Differences in anti-SARS-CoV-2 spike protein titers were statistically analysed with respect to patient-relevant factors, including age, gender, previous coronavirus disease 2019 (COVID-19) infection, systemic immunosuppressive therapy and time on dialysis.

Results: We found a favourable, but profoundly lower SARS-CoV-2 spike protein antibody response in comparison with a non-dialysis cohort (median 253.5 versus 1756 U/mL, P < 0.001). In multivariate analysis, previous COVID-19 infection (P < 0.001) and female gender were associated with a significantly higher vaccine response (P = 0.006) in haemodialysis patients, while there was a significant inverse correlation with increasing patient age and systemic immunosuppression (P < 0.001). There was no statistically significant correlation between the antibody titer and time on dialysis. Immune response in haemodialysis patients with a previous COVID-19 infection led to substantially higher antibody titers that were equal to those of vaccinated non-dialysis individuals with previous infection.

Conclusion: We strongly argue in favour of regular antibody testing after COVID-19 vaccination in haemodialysis patients. Further studies should elucidate the utility of booster vaccinations to foster a stronger and persistent antibody response.

Keywords: SARS-CoV-2; antibody response; haemodialysis; immunosuppression; vaccination.

FIGURE 1:

Antibody response in individuals previously vaccinated with mRNA-based COVID-19 vaccines. Shown are anti-SARS-CoV-2 S antibody titers in uninfected patients and with previous laboratory-confirmed SARS-CoV-2 infection. The box shows the interquartile range, the horizontal line inside the box represents the median values, whiskers represent minimum and maximum range of points within 1.5 times the interquartile range in the box. Antibody titers in samples obtained from individual patients receiving systemic immunosuppressant therapy are presented as solid circles. HD, haemodialysis patients.