Factors associated with anti-SARS-CoV-2 spike antibody titers after a second BNT162b2 mRNA COVID-19 vaccination in Japanese hemodialysis patients

BACKGROUND: We investigated factors associated with the anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike antibody titer after the second dose of the BNT162b2 messenger RNA coronavirus disease 2019 (COVID-19) vaccine in Japanese patients undergoing hemodialysis. METHODS: Overall, 75 patients (41 men, 34 women; mean age 71.4 ± 12.2 years) with a hemodialysis duration of 5.7 ± 6.1 [interquartile range, 1.0–8.5] years were enrolled in this single-center, prospective, cross-sectional study. We used multiple linear regression analysis to determine the relationships of the anti-SARS-CoV-2 spike antibody titer with patient demographic and clinical parameters. We also compared the anti-SARS-CoV-2 spike antibody titer between hemodialysis patients and 22 healthcare workers (10 men, 12 women; mean age 48.5 ± 14.4 years). RESULTS: Autoimmune disease presence (standard coefficient [β] = − 0.290, p = 0.018), lymphocyte counts (β = 0.261, p = 0.015), hemoglobin levels (β = 0.290, p = 0.009), and blood urea nitrogen concentrations (β = 0.254, p = 0.033) were significantly and independently correlated with the log-anti-SARS-CoV-2 spike antibody titer. The anti-SARS-CoV-2 spike antibody titer was significantly lower in hemodialysis patients than in healthcare workers (3589 ± 3921 [813–4468] vs. 12,634 ± 18,804 [3472–10,257] AU/mL; p < 0.002). CONCLUSIONS: Autoimmune disease presence, lymphocyte counts, hemoglobin levels, and blood urea nitrogen concentrations were associated with the anti-SARS-CoV-2 spike antibody titer after the second dose of the BNT162b2 messenger RNA COVID-19 vaccine in Japanese patients undergoing hemodialysis.