Scientists find flu and pneumonia increase risk of heart attack

♦ A bout of flu can raise the risk of a heart attack by 17 times in the week following the initial infection, scientists believe.

Heart attacks are known to increase in the winter, but until now doctors had always suspected it was down to the cold weather, which can trigger a rise in blood pressure or cause blood clotting.

But a study of more than 500 heart attack patients who were admitted to Sydney’s Royal Shore Hospital during the winter found 21 per cent had suffered a serious respiratory infection such as flu within the previous month, and 17 per cent had become infected within the previous week. Pneumonia and bronchitis also raised the risk of a heart attack by the same amount – and catching a cold raised the risk by 13 times. Associate Professor Thomas Buckley, the study investigator from Sydney Nursing School, said: “Our message to people is while the absolute risk that any one episode will trigger a heart attack is low, they need to be aware that a respiratory infection could lead to a coronary event.”