Randomized, controlled trial of high-dose influenza vaccine among frail residents of long-term care facilities

J Infect Dis. 2015 Jun 15;211(12):1915-24. doi: 10.1093/infdis/jiu622. Epub 2014 Dec 17.

Abstract

Background: Despite vaccination, residents of long-term-care facilities (LTCFs) remain at high risk of influenza-related morbidity and mortality. More-effective vaccine options for this population are needed.

Methods: We conducted a single-blinded, randomized, controlled trial comparing high-dose (HD) to standard-dose (SD) inactivated influenza vaccine (IIV) in 205 frail, elderly residents of LTCFs during the 2011-2012 and 2012-2013 influenza seasons. Hemagglutination inhibition (HI) antibody titers were measured at baseline and 30 and 180 days following vaccination.

Results: A total of 187 subjects (91%) completed the study. The mean age was 86.7 years. Geometric mean titers (GMTs) were significantly higher (P < .05) at day 30 for HD recipients, compared with SD recipients, for all comparisons except influenza A(H1N1) during 2012-2013 (the HD formulation was noninferior to the SD formulation for influenza A[H1N1] during 2012-2013). GMTs for HD and SD recipients during 2011-2012 were as follows: influenza A(H1N1), 78 (95% confidence interval [CI], 45-136) and 27 (95% CI, 17-44), respectively; influenza A(H3N2), 26 (95% CI, 17-40) and 10 (95% CI, 7-15), respectively; and influenza B, 26 (95% CI, 19-35) and 14 (95% CI, 11-18), respectively. During 2012-2013, GMTs for HD and SD recipients were as follows: influenza A(H1N1), 46 (95% CI, 33-63) and 50 (95% CI, 37-67); influenza A(H3N2), 23 (95% CI, 18-31) and 14 (95% CI, 11-18), respectively; and influenza B, 26 (95% CI, 21-32) and 17 (95% CI, 14-22), respectively. GMTs were significantly higher at day 180 for HD recipients, compared with SD recipients, for influenza A(H3N2) in both years (P < .001).

Conclusions: Among frail, elderly residents of LTCFs, HD influenza vaccine produced superior responses for all strains except influenza A(H1N1) in 2012-2013.

Clinical trials registration: NCT01654224.

Keywords: high-dose influenza vaccine; inactivated influenza vaccine; long-term care.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged, 80 and over
  • Antibodies, Viral / blood
  • Female
  • Frail Elderly*
  • Hemagglutination Inhibition Tests
  • Humans
  • Influenza A Virus, H1N1 Subtype / immunology
  • Influenza A Virus, H3N2 Subtype / immunology
  • Influenza B virus / immunology
  • Influenza Vaccines / administration & dosage*
  • Influenza Vaccines / immunology*
  • Influenza, Human / prevention & control*
  • Long-Term Care*
  • Male
  • Single-Blind Method

Substances

  • Antibodies, Viral
  • Influenza Vaccines

Associated data

  • ClinicalTrials.gov/NCT01654224