There are two major reasons why infections may be linked to heart attacks, says Sean J. Cloonan, MD, internal medicine and infectious disease physician at the Scarsdale Medical Group in New York. The first is that infections cause stress on the body.
“And any stress like this can tip somebody over the edge to having a heart attack,” Dr. Cloonan says. “Think of infection as that tipping point.” Second, infections cause inflammation in the body, he explains, which can worsen the process of plaque building up in the arteries. Read on to learn some of the infections that can worsen heart trouble.
A study from the London School of Hygiene and Tropical Medicine that was published in The New England Journal of Medicine found that influenza was one of the respiratory illnesses that raised the risk of a heart attack and stroke. Risk increased sharply among the study participants in the first few days after diagnosis. However, receiving the flu vaccine did not increase the risk, so get your flu shot if you can.
Bronchitis is an inflammation of the lining of the lungs that is often caused by an infection, and it can raise the risk of a heart attack or stroke, according to The New England Journal of Medicine study. The researchers found that heart attack risk rose fivefold and stroke risk increased threefold during the first three days following the diagnosis of a respiratory tract infection. The risk declined over time, however, and was nearly normal within three months after people recovered from the infection.
Another problematic respiratory infection: pneumonia. A study in the European Journal of Preventive Cardiology found that patients who had lung infections requiring a hospital admission had a six times greater risk for cardiovascular disease in the year following the illness, compared to people who hadn’t had the infections.
And the risk persisted over time: It was more than twice as high for the hospitalized patients two and three years after the event and remained elevated up to five years after. A study in the Journal of the American Medical Association produced a similar finding.
Other respiratory infections
A study conducted by researchers at Aston Medical School in Birmingham, UK, and presented at the American College of Cardiology conference in 2019 found that respiratory infections could raise the risk of a heart attack and double the risk of a stroke caused by atherosclerosis (the buildup of plaque in the arteries). In fact, researchers said the risk could be greater than the risk posed by obesity and similar to the dangers of high blood pressure and diabetes.
Urinary tract infections (UTIs)
UTIs pose a similar heart attack risk. A study in the Journal of the American Heart Association found that one of the most common infections preceding coronary heart disease events and stokes were urinary tract infections, followed by pneumonia, cellulitis (a potentially serious deep tissue infection), and blood infections.