Influenza Infection Increases Mortality Risk in Acute Myocardial Infarction

Influenza infection was independently associated with increased mortality risk in patients in whom AMI developed.
Influenza infection was independently associated with increased mortality risk in patients in whom AMI developed.

The following article is part of conference coverage from the 2018 AHA Scientific Sessions in Chicago, Illinois. MPR's staff will be reporting breaking news associated with research conducted by leading experts in cardiology. Check back for the latest news from AHA 2018.

Influenza infection independently increased the mortality risk in those who had acute myocardial infarction (AMI) but was not a risk factor for the development of AMI, according to research presented at the AHA Scientific Sessions 2018 held in Chicago, Illinois, November 10-12, 2018.

Researchers analyzed data from the USA Nationwide Inpatient Sample database from 2012 to 2014 to determine whether influenza infection was an independent risk factor for the development of AMI.

A total of 2146 patients with influenza and AMI and 563,227 patients with AMI only were included in the study. The mean age of patients with influenza and AMI was 72.67 years and for those with AMI only the mean age was 68.82 years (P<.001). More women had both influenza and AMI vs AMI alone, 48.45% vs 41.67%, respectively (P<.001). 

The cost was higher and the hospital stay longer for patients with both influenza and AMI vs for patients with AMI alone ($98.24 USD and 8.8 days vs $81.88 USD vs 5.84 days, respectively; P<.001 for both). 

After adjusting for comorbidities, the adjusted odds ratio for patients with influenza having an AMI was 0.84 (95% CI, 0.80-0.89; P<.001). In patients with influenza-associated with mortality in AMI, the adjusted odds ratio was 1.34 (95% CI, 1.13-1.58; P<.001).

Patients with influenza and AMI had increased length of hospital stay and in-hospital costs. Patients with influenza and AMI were more likely to be older in age and female.

Related Articles

For more coverage of AHA 2018, click here.

Last, investigators observed that influenza was not a risk factor for AMI developing but independently increased the risk for mortality in those in whom AMI developed.

Reference

Gul MH, Htun ZM, Aye HH, Lwin, AK, Myint M. Influenza is associated with worse outcomes in acute myocardial infarction. Presented at: American Heart Association Scientific Sessions 2018; November 10-12, 2018; Chicago, IL. Abstract Sa2063/2063.