The Flu and Heart Disease: The Surprising Connection That Should Convince You to Schedule Your Vaccination
A new study shows that patients with cardiovascular disease have an increased risk of serious complications from the flu, whether they have reached retirement age or not. Influenza virus infection in patients with CVD is associated with an increased risk of cardiovascular events. Under these conditions, the administration of the influenza vaccine substantially reduces the cardiovascular risks.
It is well known that the flu can lead to significant respiratory symptoms such as pneumonia, bronchitis and bacterial infection of the lungs. The effects of the virus on the heart have historically been more difficult to analyze because many patients already have a known predisposition to heart events, but also because the heart event often occurs a few weeks after the onset of the flu.
Recent research shows that patients are six times more likely to have a heart attack in the week after the flu infection than at any time in the year before or the year after the infection. In a study that looked at 336,000 hospitalizations for the flu, 11.5 percent had a serious heart attack.
Another study that looked at 90,000 laboratory-confirmed flu infections showed a strikingly similar rate of 11.7% for an acute cardiovascular event.
One in eight hospitalized patients with the flu, 12.5% suffered a cardiovascular event, 31% were transferred to intensive care and 7% died as a result of the event.
The reason why the flu affects both the heart and the vascular system is related to the body’s inflammatory response to the infection.
Inflammation occurs when the body’s “first responders,” specifically the white blood cells and what they produce to protect you, gather in an area and begin to work against an infection, bacteria, or virus. When you are sick, you can usually feel the effects of these “fighting areas” in swelling, tenderness, pain, weakness, sometimes redness, but also high temperature of the joints, muscles and lymph nodes.
Increased activity can also cause a kind of blockage that leads to the formation of blood clots, high blood pressure and even swelling or scarring in the heart. Additional stressors make the artery plaque more vulnerable to rupture, causing a blockage that cuts off oxygen to the heart or brain and results in heart attacks or strokes.
In addition, non-cardiac complications of viral disease, including pneumonia and respiratory failure, may worsen the symptoms of heart failure or cardiac arrhythmia. In short, the extra stress on the cardiovascular system could be overwhelming for an already weakened heart muscle.
Because influenza viruses are constantly mutating, scientists change the vaccine every year to match the probable components. On average, it is effective in preventing infection 40% of the time. While this may not seem important, it is enough to significantly reduce the risk of severe illness in most people.
Recently, studies have shown that the vaccine is not only effective in protecting the general population and the most vulnerable age groups (over 65 and under 2 years) from severe cases of influenza, but also acts as a protection against cardiovascular mortality, especially among the high-risk population.
Adults who received the vaccine were 37% less likely to be hospitalized and 82% less likely to be taken to intensive care because of the flu virus. Among those hospitalized with the flu, vaccinated people were 59% less likely to be admitted to the ICU. Vaccinated patients admitted to the ICU spent four days less in the ICU than unvaccinated patients.
Due to the proven benefits of influenza vaccination and the risks of influenza infection among those with cardiovascular disease, many international companies strongly recommend annual influenza vaccination to patients with cardiovascular disease.