Influenza activity tied to increase in HF hospitalizations

  • Kytömaa S et al.
  • JAMA Cardiol
  • 27 Mar 2019

  • International Clinical Digest
Access to the full content of this site is available only to registered healthcare professionals. Access to the full content of this site is available only to registered healthcare professionals.


  • An increase in population-level influenza activity/influenza-like illness (ILI) is associated with increased hospitalizations for heart failure (HF).

Why this matters

  • ILI presenting in a broad range of patients may increase risk for acute cardiovascular events and related hospitalizations, especially during peak influenza activity.

Key results

  • Unweighted total 3541 and 4321 hospitalizations for MI and HF, respectively.
  • Absolute 5% increase in monthly ILI activity associated with 24% increase in HF hospitalization rates in the same month (incidence rate ratio [IRR], 1.24; 95% CI, 1.11-1.38; P<.001>
  • A 22% and 20% temporally associated increased HF risk was observed during severest influenza seasons 2010-2011 (IRR, 1.22; 95% CI, 1.01-1.49; P=.04) and 2012-2013 (IRR, 1.20; 95% CI, 1.02-1.40; P=.02), respectively.
  • Overall influenza activity was not significantly associated with MI hospitalizations (IRR, 1.02; P=.72).
  • HF hospitalization risk reduction noted with reduced ILI activity (IRR, 0.81; 95% CI, 0.72-0.90/absolute 5% decline in ILI), suggesting that it was 19% higher in months with elevated ILI activity vs baseline.

Study design

  • Population-based surveillance study examining temporal ILI and MI, HF hospitalizations in community-dwelling adults, October 2010-September 2014.
  • Funding: NIH.


  • Individual-level ILI, MI/HF hospitalizations unknown.
  • Other infections possibly linked to events.
  • Inconsistent influenza severity data.
  • Nongeneralizable.
  • Sampling bias.

Please confirm your acceptance

To gain full access to GPnotebook please confirm:

By submitting here you confirm that you have accepted Terms of Use and Privacy Policy of GPnotebook.