A new Canadian study suggests that patients with a history of heart disease who get the flu shot could reduce their risk of a heart attack or stroke by more than half.
The study, published Tuesday in the Journal of the American Medical Association, showed that patients with acute coronary syndrome -- which means they recently had a heart attack or had unstable angina -- had a 36 per cent lower risk of a major cardiovascular event, such as a heart attack, stroke or heart failure, within a year of receiving a seasonal flu vaccine.
Those who specifically suffered a heart attack recently, they had a 55 per cent lower risk of a major cardiac event after receiving the vaccine.
The study reviewed six clinical trials on heart health in people who had received the flu vaccine. The studies included more than 6,700 patients with acute coronary syndrome and who had an average age of 67.
They found that among those who didn't get a flu vaccine or who got a placebo, 4.7 per cent (151 patients) had a major cardiovascular event, such as a heart attack or stroke, within a year. But among the patients who did get the vaccine, only 2.9 per cent (95 people) had a major cardiovascular event.
When the researchers looked at patients with pre-existing coronary artery disease and a recent heart attack or unstable angina, the risk of major heart or vascular event was especially lower among those who had the flu vaccine -- 10.3 per cent vs. 23.1 per cent.
"If the flu vaccine can reduce the risk of cardiac events, these shots could have considerable impact on cardiac health," lead researcher Dr. Jacob Udellsaid in a statement.