Antibody response to seasonal influenza vaccination in patients with multiple sclerosis receiving immunomodulatory therapy.

BACKGROUND AND PURPOSE: We have previously shown that patients with multiple sclerosis receiving immunomodulatory treatment have reduced seroprotection rates after influenza immunization. The aim of this study was to further investigate the influence of immunomodulatory therapies on the antibody response and seroprotection rates in patients immunized with seasonal influenza vaccine in 2012/2013 compared with healthy controls. METHODS: Ninety patients receiving fingolimod, glatiramer acetate, interferon beta-1a/1b, natalizumab or no therapy were compared with 62 healthy controls. All subjects received the inactivated split virus vaccine in 2012 and serum samples were collected pre-vaccination and 3, 6 and 12 months post-vaccination. The vaccine responses were evaluated by the hemagglutination inhibition assay and adjusted for age and gender. RESULTS: No significant differences in rates of protection against H1N1 for interferon beta-1a/1b and glatiramer acetate were observed as compared with controls at 3, 6 and 12 months. Fingolimod provided reduced protection at all time points post-vaccination, whereas natalizumab displayed reduced protection at 3 and 6 months. Patients without immunomodulation did not display protection rates that were significantly different from the controls at 3 and 12 months. CONCLUSION: These findings suggest that patients with multiple sclerosis receiving fingolimod or natalizumab should be considered for a second dose of the vaccine in cases of insufficient protection. Our results further indicate that new immunomodulatory treatment regimens should be systematically evaluated for their influence on influenza-specific vaccine responses.

Self-reported influenza vaccination and protective serum antibody titers in a cohort of COPD patients.

BACKGROUND: COPD patients are advised vaccination against seasonal influenza, yet few studies have evaluated the protective antibody titers obtained in this patient group. AIMS: 1) To describe protective titers in COPD patients who self-reported influenza vaccination compared with vaccinated subjects without COPD and unvaccinated COPD patients, 2) analyze whether clinical parameters predicted influenza-specific antibody titers, and 3) whether antibody titers to influenza A at baseline could predict exacerbation risk or 5 years all-cause mortality. METHODS: Influenza A (H1N1 and H3N2) titers were measured by haemagglutination inhibition assay in serum from 432 COPD patients and 77 controls in the Bergen COPD Cohort Study, at yearly visits between 2006/09. Titers of 40 or above were considered protective. We examined the variables sex, age, body composition, smoking, GOLD stage, yearly exacerbations, inhaled steroids, and Charlson score as predictive of titers, both univariately and in a multivariable model estimated by generalized estimating equations. The exacerbation incidence rate ratios and mortality hazard ratios were assessed by negative binominal and cox regression models respectively. RESULTS: At baseline, 59% of COPD patients reported influenza vaccination during the last season. Levels of predictive titers varied considerably each season, but trended lower in COPD patients compared with controls. Neither sex, age, body composition, smoking, comorbidities, GOLD stage nor use of inhaled steroids consistently predicted titers. Having high titers at baseline did not impact later risk for exacerbations, but seemed to be associated with higher all-cause mortality, even after adjustment for COPD disease characteristics. CONCLUSION: Vaccination coverage for influenza is imperfect for COPD patients in Norway, and there is a concern that immunization is suboptimal.