Australian doctors say the risk of having a heart attack is 17 times higher in people who have had a recent respiratory infection. Professor Geoff Tofler, from the University of Sydney and the Royal North Shore Hospital, said the increased risk was not just at the beginning of respiratory symptoms. “It peaks in the first seven days and gradually reduces but remains elevated for one month,” he said. “This is the first study to report an association between respiratory infections such as pneumonia, influenza and bronchitis and increased risk of heart attack in patients confirmed by coronary angiography (a special x-ray to detect heart artery blockages).” The findings have been published in the Internal Medicine Journal. “Our findings confirm what has been suggested in prior studies: that a respiratory infection can act as a trigger for a heart attack,” Professor Tofler said. Heart disease is the biggest killer in Australia, yet it seems many of us are unaware we are at risk. Doctors say there are several reasons why a respiratory infection might increase heart attack risk. It could be that the infection activates blood cells and the clotting system, leading to increased risk of blood clots. Patients were interviewed about their health before the heart attack, including if they had a recent “flu-like illness with fever and sore throat”. They were considered affected if they reported sore throat, cough, fever, sinus pain, flu-like symptoms, or had a diagnosis of pneumonia or bronchitis. Professor Tofler said while the absolute risk that any one respiratory infection will trigger a heart attack is low, patients need to be aware that it could lead to a coronary event. “So consider preventative strategies where possible, and don’t ignore symptoms that could indicate a heart attack,” he said. Associate Professor Thomas Buckley, from the Sydney Nursing School, said the incidence of heart attacks is at its highest during winter. “This winter peak, seen not only in Australia but also in other countries around the world, is likely due in part to the increased incidence of respiratory infections,” he said. “People should take measures to reduce exposure to infection, including flu and pneumonia vaccines where appropriate.” Professor Tofler said while the absolute risk that any one respiratory infection will trigger a heart attack is low, patients need to be aware that a respiratory infection could lead to a coronary event. “So consider preventative strategies where possible, and don’t ignore symptoms that could indicate a heart attack,” he said. Doctors now want further studies to treat respiratory conditions in those patients who might be susceptible.
ABC Health News, 16 May 2017 ;http://www.abc.net.au/news/ ;