Through a 2013 study published in the Journal of the American Medical Association (JAMA), researchers determined that people at high risk of having major cardiovascular events may reduce their risk of future events that year by getting a flu shot, especially if they have recent ACS. (ACS, or Acute Coronary Syndrome, is an umbrella term for heart attacks and unstable angina – situations where there’s a sudden block of blood supply to the heart.)
The researchers systematically reviewed and meta-analyzed data from 6 studies: Within the time of follow up (within a year – an average of 7.9 months later), 2.9% of the 3,238 participants who had received a flu vaccine had suffered a major adverse cardiac event, as compared to 4.7% of the 3,232 participants who received the placebo or control.
Mainstream media outlets publicized this study – just in time for flu season – with headlines such as: “The Flu Shot Could Cut Risk of Heart Attack and Stroke” (Forbes) and “Flu shots may reduce risk of heart attacks, strokes and even death.” (LA Times), potentially creating confusion about who exactly stands to have their risk cut.
While the very young and the elderly are at the highest risk of serious complications from the flu virus, the CDC recommends that everyone over the age of 6 months receive annual flu vaccinations.
Access the JAMA study here.
My Viewpoint: At best, this study suggests a correlation between the flu shot and future coronary events. It does not prove that the flu shot can prevent coronary events or that coronary events are caused by the flu. It certainly does not show that getting an annual flu shot will protect the average person against a major cardiovascular event. What it does show, is that flu shots may be warranted to protect fragile health in those who are in the extremely vulnerable position of having just suffered from ACS (a heart attack or episode of angina while at rest).
What This Means to You: If you are healthy or have stable coronary artery disease, I would not run out and get a flu shot based on the findings in this study. If you have unstable CAD and are at higher risk of having a coronary event, or you have recently had an ACS, you and your doctor may want to consider adding the flu shot to your health regimen.
Recommendation: I continue to recommend that if you are healthy, forget the flu shot – it can actually weaken your immune system and you may still get the flu! Read Cold and Flu Prevention and Beta Glucan for tips on how to naturally prevent and combat the flu. If you live in a nursing home, or have a comprised immune system or lung problems, I continue to recommend getting a flu shot. In light of this study, I would also extend this limited flu shot recommendation to you if you have unstable CAD or have recently suffered a coronary event and are in a very vulnerable and fragile state of health – and only until you are “out of the woods,” so to speak, and not annually and indefinitely.
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