Note: This report has an update: see Vaccine/Heart Attack Study Questioned
From the Canadian Medical Association Journal (CMAJ) today we get a study that strongly suggests that those over the age of 40 who get a seasonal flu vaccine each year may reduce their risk of a heart attack by as much as 19%.
The same, alas, could not be said for the pneumococcal (pneumonia) vaccination.
Early vaccination was associated with a lower rate of heart attack than getting the shot after mid-November.
A. Niroshan Siriwardena PhD FRCGP, Stella M. Gwini MSC, Carol A.C. Coupland CStat PhD
September 20, 2010
Heart attack occurred less frequently in people who had had a recent influenza vaccination than in those who had not, but the same could not be said for pneumococcal vaccination. Siriwardena and colleagues found this association in a case–control study using a large database of general practice patients in the United Kingdom. If influenza vaccination does have the added benefit of reducing heart attacks, then it may be important to vaccinate early in the season, say the authors.
Given the burden that influenza can place on a person’s health – particularly when that person has underlying coronary disease – it makes sense that some number of heart attacks are likely brought on by this illness.
Since yearly flu vaccines reduce the incidence of influenza, by that logic they should also tend to reduce the number of heart attacks as well.
And based on this study at least, that logic appears to hold.
While a single study will not be the last word on this subject, for those of us over 40, this is a pretty good reason to get that flu shot every year.