Researchers from the University of Sydney discovered that after experiencing a respiratory infection, the risk of a heart attack increases significantly. The risk, according to the researchers, is as much as 17 times higher just one week after a respiratory infection. This includes infections and diseases such as the flu, bronchitis, or pneumonia. The study was the first of its kind and was recently published in the Internal Medicine Journal.
Respiratory tract infections can be classified as upper or lower respiratory tract infections. Lower respiratory tract infections include pneumonia and are more serious than upper respiratory tract infections which include the cold. The upper respiratory tract includes the nasal cavity, pharynx, and larynx while the lower respiratory system includes the trachea, bronchi, and the lungs. Lower respiratory tract infections can be deadly if not treated properly. Bronchitis and pneumonia are two diseases that target the lower tract while infections such as the flu tend to affect both the upper and lower respiratory tracts.
According to the press release from the University of Sydney, a coronary angiography was used to confirm the risk of heart attacks. The coronary angiography is a type of x-ray device that is used to find blockages in the heart. Geoffrey Tofler, a professor at the University of Sydney, said that the study’s results confirmed previous studies “that a respiratory infection can act as a trigger for a heart attack.” Tofler is also a cardiologist at the Royal North Shore Hospital and Heart Research Australia. The risk for a heart attack is not present at the start of a respiratory tract infection but one week after the risk peaked and slowly drops over the next month but remains “elevated.”
Tofler and his team of researchers studied almost 600 heart attack patients. The data they collected informed the team about the patients’ infections, with 17 percent of the patients reporting infections within a week of the heart attack and 21 percent within one month. The researchers interviewed the patients regarding their activities and specifically asked questions about any flu-like symptoms they had. Lorcan Ruane, a lead author, said for patients with mild upper infections the “risk was less but still elevated.” Ruane went on to say it was “important to understand” how one influenced the other.
Thomas Buckley, an associate professor, said that heart attacks increase during the winter season in Australia and also around the world. Buckley also added that people needed to be cautious to reduce their exposure to infection. Tofler added that a theory about the relationship between heart attacks and respiratory infections could be the increased blood clotting and inflammation. He wen on to say that toxins could also hurt blood vessels. He cautioned the public to know the risks and added that further research was needed especially in finding treatment decreasing heart attacks.
By Cheryl Werber
Photo Courtesy CDC