Vitamin D levels and influenza vaccine immunogenicity among HIV-infected and HIV-uninfected adults

Vaccine. 2016 Sep 22;34(41):5040-5046. doi: 10.1016/j.vaccine.2016.06.019. Epub 2016 Aug 28.

Abstract

Background: Vaccination is the most important preventive strategy against influenza, however post-vaccination antibody responses are often inadequate especially among HIV-infected persons. Vitamin D deficiency has been suggested to adversely influence immune responses and is highly prevalent among HIV-infected adults. Therefore, we evaluated the association between 25-hydroxyvitamin D [25(OH)D] levels and post-influenza vaccination responses.

Methods: We conducted a prospective cohort study evaluating the immunogenicity of monovalent influenza A (H1N1) vaccination among both HIV-infected and HIV-uninfected adults (18-50years of age) during the 2009-2010 influenza season. Antibody titers were evaluated at baseline, day 28, and 6months post-vaccination using hemagluttination inhibition assays. Serum 25(OH)D levels were measured at day 28. Univariate and multivariate regression analyses examined the association between 25(OH)D levels [categorized as <20ng/ml (deficiency) vs. ⩾20ng/ml] with the primary outcome of seroconversion. Secondary outcomes included seroprotection; a ⩾4-fold increase in titers; and geometric mean titers post-vaccination. Analyses were repeated using 25(OH)D levels as a continuous variable.

Results: A total of 128 adults [64 HIV-infected (median CD4 count 580cells/mm(3)) and 64 HIV-uninfected] were included. Seroconversion at day 28 post-vaccination was achieved in fewer HIV-infected participants compared with HIV-uninfected participants (56% vs. 74%, p=0.03). Vitamin D deficiency was more prevalent among HIV-infected persons vs. HIV-uninfected persons (25% vs. 17%), although not significantly different (p=0.39). There were no associations found between lower 25(OH)D levels and poorer antibody responses at day 28 or 6months for any of the study outcomes among either HIV-infected or HIV-uninfected adults.

Conclusion: Vitamin D deficiency was common among both HIV-infected and HIV-uninfected adults, but lower levels did not predict antibody responses after H1N1 (2009) influenza vaccination. Low 25(OH)D levels do not explain poorer post-vaccination responses among HIV-infected persons.

Keywords: HIV-infected persons; Immunogenicity; Influenza vaccine; Vitamin D level.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Antibodies, Viral / blood
  • Antibody Formation
  • CD4 Lymphocyte Count
  • Female
  • HIV Infections / immunology*
  • Humans
  • Immunogenicity, Vaccine*
  • Influenza Vaccines / immunology*
  • Male
  • Middle Aged
  • Prospective Studies
  • Vitamin D / analogs & derivatives
  • Vitamin D / blood*
  • Vitamin D Deficiency / blood
  • Young Adult

Substances

  • Antibodies, Viral
  • Influenza Vaccines
  • Vitamin D
  • 25-hydroxyvitamin D