Humoral antibody response to the first dose of the ChAdOx1 nCoV-19 vaccine in Asian patients undergoing hemodialysis

Background and objectives: The immunogenicity of vaccines is known to be attenuated in patients with end-stage kidney disease due to uremia. Patients on dialysis were excluded from coronavirus disease 2019 (COVID-19) vaccine trials; thus, the effectiveness of vaccines for this population is unclear. The aim of this study was to explore whether Asian dialysis patients can effectively produce an immune response after being vaccinated with the first dose of the ChAdOx1 nCoV-19 vaccine.

Design setting, participants, and measurements: In this prospective cohort study, we included Asian hemodialysis patients who received the ChAdOx1 nCoV-19 vaccine. At 3 weeks after the first dose of vaccination, we assessed the humoral immune response by measuring anti-SARS-CoV-2 S antibody titers. The primary outcome was the seropositive rate following vaccination, defined as an antibody titer greater than or equal to 0.8 U/ml. Factors associated with seropositivity were explored in multivariate logistic regression analyses.

Results: In total, 434 participants were included. The mean age was 64 years, the mean dialysis vintage was 6 years, and 61% of the participants were men. At a mean time of 22 days from vaccination, 56% of the participants were seropositive. The vast majority (88%) had low antibody titers (< 15 U/ml). The multivariate logistic regression analyses showed that older age (every increase of 10 years, odds ratio [OR] 0.80, 95% CI 0.65-0.98, p = 0.03) was negatively associated with seropositivity and that higher Kt/V (every increase of 0.1, OR 1.14, 95% CI 1.01-1.28, p = 0.03) and higher serum albumin level (every increase of 0.1 g/dl, OR 1.09, 95% CI 1.02-1.18, p = 0.02) were positively associated with seropositivity.

Conclusions: In Asian hemodialysis patients, the seropositive rate was low, and most had low antibody titers after the first dose of the ChAdOx1 nCoV-19 vaccine. Younger age, better dialysis adequacy, and higher albumin levels were associated with seropositivity.