A person who has the flu is six more times likely to suffer a heart attack, the Daily Mail reported.
A team at Public Health Ontario, Canada, found the association between the two after analysing close to 20,000 Ontario adult cases of influenza infection from 2009 to 2014. They discovered 332 patients were hospitalised for a heart attack, within just one year of a flu diagnosis.
While the study also found heart attack risk from various other respiratory viruses, the flu seemed to be the most lethal.
The study's findings stress the need for people at risk of a heart attack to get a flu shot. The risk may be particularly higher for patients who experience a heart attack for the first time, patients with influenza B infections and older adults.
"Our findings are important because an association between influenza and acute myocardial infarction reinforces the importance of vaccination," lead author of the study Doctor Jeff Kwong told the Daily Mail.
Adding, "Our findings, combined with previous evidence that influenza vaccination reduces cardiovascular events and mortality, support international guidelines that advocate for influenza immunisation in those at high risk of a heart attack."
Those at risk of heart disease need to take precaution, Dr Kwong warned. Vaccinations and washing your hands are some of the suggestions he made. Getting a medical check for symptoms of the condition are crucial within the first week of having an acute respiratory infection, researchers urge.
The study's findings were originally published in the New England Journal of Medicine.