Influenza: Six times the risk of a heart attack

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The flu is very hard on the body. Many still feel tired and weak for a long time after the high fever and respiratory symptoms have subsided. The disease can also hit the heart. The risk of a heart attack is apparently greatly increased during the flu.

Researchers from the University of Toronto analyzed data from 364 patients who had flu between 2009 and 2014. In addition, all participants had suffered a heart attack within one year before or after the infection.

The scientists compared how many patients had a heart attack within seven days of being diagnosed with the flu, or before or after the disease resolved.

Risk increased six times

The result: In the week in which the body was also burdened by the flu, a total of 20 patients suffered a heart attack. In the rest of the time studied, there was an average of only 3.3 cases per week. The influenza virus increased the risk of myocardial infarction six-fold.

Of course, infectious diseases other than the flu can also weaken the body. The researchers also observed a slightly increased risk of heart attack for other respiratory diseases, such as certain cold viruses. However, the effect was significantly less here.

Pathogen detection in the laboratory

In contrast to earlier studies that investigated this connection, the flu diagnoses were here for the first time confirmed by an influenza detection in the laboratory. If they are based only on the patient's complaints, misdiagnoses sometimes occur, as acute respiratory infections caused by other pathogens can cause similar symptoms.