Risk factors affecting seroconversion after influenza A/H1N1 vaccination in hemodialysis patients

摘要

Background Hemodialysis (HD) patients have multiple causes of immune dysfunction and poor immune response to influenza vaccination. We investigated the antibody response rate to a pandemic H1N1/2009 influenza vaccination and clinical parameters influencing the induction of antibody responses in HD patients. Methods A total of 114 HD patients were vaccinated with a monovalent adjuvanted H1N1 inactivated influenza vaccine. Titers of neutralizing antibodies were evaluated by hemagglutination inhibition (HI) assay at pre- and 4?weeks after vaccination. Seroconversion was defined as either a pre-vaccination HI titer??1:40 or a pre-vaccination HI titer?≥?1:10 and a minimum four-fold rise in post-vaccination HI antibody titer. Seventeen out of 114 HD patients (14.9%) tested positive for antibodies against influenza A/H1N1/2009 before vaccination. The remaining 97 baseline sero-negative patients were included in the analysis. Results Only 30 (30.9%) HD patients had seroconversion 4?weeks after vaccination. The elderly patients, those over 65?years of age, showed significantly lower seroconversion rate compared to younger HD patients (20.5% vs. 39.6%, p?=?0.042). Furthermore, patients with hemoglobin values less than 10?g/dL had a significantly lower seroconversion rate compared to those with higher hemoglobin values (20.0 vs. 38.6%, p?=?0.049). By multivariate logistic regression analysis, only age ≥65?years (OR?=?0.336, 95% confidence interval (CI) 0.116-0.971, p?=?0.044) and hemoglobin levels Conclusions Our data show that HD patients, especially who are elderly with low hemoglobin levels, are at increased risk for lower seroconversion rate after influenza A/H1N1 vaccination. Further studies are needed to improve the efficacy of vaccination in these high risk patients.