High- vs standard-dose influenza vaccine: similar outcomes for high-risk cardiopulmonary patients

  • Vardeny O & al.
  • JAMA
  • 04/12/2020

  • Liz Scherer
  • Clinical Essentials
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Takeaway

  • Compared with standard-dose influenza vaccine, the high-dose trivalent influenza vaccine is not associated with reduced all-cause mortality or hospitalizations in high-risk cardiopulmonary patients.

Why this matters

  • Editorial notes that outcomes were nonspecific, rather than laboratory-confirmed influenza, and adds that results "should not be interpreted to mean that influenza vaccines are ineffective" or that protection against lab-confirmed influenza is the same between these 2 vaccines.
  • "Vaccination with current age-appropriate quadrivalent influenza vaccines that are partially effective is still better than no vaccination," especially in this patient group.

Key results

  • 5260 participants in efficacy analysis; mean age, 65.5 (standard deviation, 12.6) years over 3 seasons.
  • High dose: 884 participants, 975 primary events (883 hospitalizations, 92 deaths); event rate, 45/100 patient-years.
  • Standard dose: 837 participants, 924 primary events (846 hospitalizations, 78 deaths); event rate, 42/100 patient-years.
  • High-dose vs standard: HR, 1.06 (P=.21).
  • Results were qualitatively similar for primary endpoint components within each season.
  • Adverse events: injection site pain (26.5%), myalgia (17.7%), swelling (6.1%) more common in high-dose group.
  • Serious adverse event rates were similar between groups.

Study design

  • Pragmatic, multicenter, double-blind, active comparator randomized study.
  • Adult patients with acute myocardial infarction or heart failure plus 1 additional condition.
  • Funding: National Heart, Lung, and Blood Institute; Sanofi Pasteur.

Limitations

  • Unable to assess influenza-specific effects.
  • No placebo control.
  • Limited generalizability.