New research reveals the possibility that flu shots can also lower the risk of heart diseases, aside from its main purpose of flu prevention.
Dr. Jacob Udell, lead author of the study from the University of Toronto's Women's College Hospital, used existing data from earlier studies. Their investigations involved poring over trials in which they were able to collate comparisons of patients who had flu shots and people who hadn't.
The researchers studied two studies involving 6,735 patients whose age averaged around the late 60s. More than 30 percent of them had histories of heart diseases.
The researchers discovered that, compared to those who had fake flu shots, those who had flu shots showed less chance of contracting heart diseases within or after a year. It was particularly pronounced in those patients who had earlier heart problems.
Those under placebo shots had five percent chances of having heart diseases like stroke and heart attacks, while those who had flu vaccinations only had three percent chance.
Among those who had heart problem histories, 10 percent of those who had flu shots had heart issues within the year, while those who had placebo shots had 23 percent.
There were earlier studies indicating an increased risk of heart diseases shortly after a patient had flu. It is speculated that the flu virus impacts the body through swelling of parts of the body which in turn makes existing heart diseases worse.
"If there are those out there who for whatever reason don't get the flu shot or don't feel that they need it … this is one more reason why they might help," Dr. Udell told Reuters Health.
Dr. David Frid, who was not involved in the study, told Reuters, "From the clinical perspective, it gives us more supporting data to say to our patients, ‘Here's a recent study confirming what we've been telling you that if you have heart disease you should be getting the flu vaccine."
The study was published in the Oct. 22 issue of the Journal of the American Medical Association.
