Find links between flu and heart attacks

According to a study, published in the New England Journal of Medicine, the chances of a heart attack multiply six-fold during the first seven days after laboratory-confirmed influenza infection is detected.
Our findings, explains study lead author Jeff Kwong in a news release, are important because an association between influenza and acute myocardial infarction reinforces the importance of vaccination. Our findings, combined with previous evidence that influenza vaccination reduces cardiovascular events and mortality, support international guidelines that advocate influenza immunization in people at high risk for heart attack.

In the study, researchers found a significant association between acute respiratory infections, particularly influenza, and acute myocardial infarction.
The risk may be increased for older adults, patients with influenza B infections, and those who experience their first heart attack. The researchers also found an elevated risk, although not as high as for influenza, of infection with other respiratory viruses.
The researchers analyzed nearly 20,000 adult cases of laboratory-confirmed influenza infection between 2009 and 2014 and identified 332 patients who were hospitalized for a heart attack within one year of a laboratory-confirmed influenza diagnosis.

People at risk for heart disease should take precautions to prevent respiratory infections, and especially the flu, through measures including vaccination and handwashing, Kwong concludes.
The researchers add that patients should not delay medical evaluation of heart symptoms, particularly during the first week of an acute respiratory infection.