Purpose The predictive value of antibody titers after the first SARS-CoV-2 vaccination and long-term trajectories of antibody titers in hemodialysis patients are unknown. Methods SARS-CoV-2 IgG antibodies and their neutralizing effect six weeks after the first and second vaccination were analysed in 30 hemodialysis patients. IgG titers served to classify participants as responders or non-responders and to calculate sensitivity, specificity, and accuracy. Associations between potential risk factors and post-vaccine non-response were analysed by Mann–Whitney- U test and Chi-Squared test. Long-term follow-up analysis (ANOVA) on the evolution of neutralizing IgG-titers was performed in 24 participants 94 and 135 days after the second immunization. Results IgG antibodies ≥ 1 AU/L (mean 9 ± 20 AU/L) after the first dose were found in 20 patients (66.7%). After the second dose only two participants (6.7%) remained sero-negative and 16.6% showed neutralizing levels below 30%, whereas 25 patients showed IgG antibodies with the high neutralizing activity of 86 ± 18%. Positive IgG antibodies 6 weeks after the first vaccination predicted vaccination effectiveness after two cycles with a specificity of 100%, sensitivity of 76%, and accuracy of 87%. Even low-dose immunosuppressive therapy increased the relative risk for non-response after the first and second dose 1.9 (95% CI 0.8–4.6) and 4.9 (95% CI 1.0–23.8) times, respectively. Over a period of about 4.5 months IgG titers slowly declined by 51% from baseline or by 0.45 AU/mL per day, respectively. Conclusion Two cycles of SARS-CoV-2 vaccination-induced high seroconversion rates comparable to the general population. Immunosuppressive medication is a major risk factor for vaccination non-response. Mounted IgG antibodies showed a high neutralizing capacity as evidence of protective effectiveness. IgG antibodies after the first dose may serve to predict later vaccination outcome. Patients on dialysis display a more rapid decline in antibody titers on long-term follow-up compared to healthy controls.
【저자키워드】 COVID-19, SARS-CoV-2, vaccination, Neutralizing antibodies, Hemodialysis, Antibody titer trajectory, Long-term follow-up, 【초록키워드】 Evolution, IgG, therapy, risk, outcome, risk factor, Relative risk, immunization, dialysis, Predictive value, sensitivity, specificity, Neutralizing activity, Hemodialysis, IgG antibody, Accuracy, IgG antibodies, SARS-CoV-2 IgG antibody, low-dose, Patient, Antibody titer, Effectiveness, trajectory, Neutralizing, neutralizing capacity, Follow-up, General population, Responder, medication, patients, predict, SARS-CoV-2 IgG, Antibody titers, SARS-CoV-2 vaccination, Protective, immunosuppressive therapy, Evidence, IgG titer, Analysis, immunosuppressive, Long-term follow-up, evidence of, Predictive, Factor, 95% CI, second vaccination, second dose, first dose, potential risk, SARS-CoV-2 IgG antibodies, participant, healthy controls, responders, seroconversion rate, ANOVA, first vaccination, Chi-squared test, IgG titers, first and second dose, over, Post-vaccine, neutralizing effect, Immunosuppressive medication, non-responder, positive IgG antibodies, Result, predicted, remained, was performed, analysed, per day, comparable, declined, baseline, calculate, 【제목키워드】 Patient, trajectory, SARS-CoV-2 neutralizing antibody, Predictive,