Wednesday, September 22, 2010
FLU (including H1N1) Vaccination decreases Heart attack risk by 19% - Universit of Lincoln,UK Study
It has been suggested there may be an association between respiratory infections and heart attacks - both increase in incidence significantly in the winter months when flu and pneumonia are prevalent.
The British researchers examined data on 78,706 patients aged at least 40 years from 379 GP (general practitioner, primary care physician) practices in England and Wales. 16,012 of the patients had had a heart attack, of whom 8,472 had received a seasonal flu shot.
The investigators found a link between those who had been vaccinated and a significant reduction in heart attack risk. The pneumococcal vaccination was not linked to any additional benefit, the authors added.
Those who were vaccinated between September and mid-Novembers (early vaccinations) had a 21% heart attack reduction risk, while patients who received the vaccination later had a 12% reduction risk.
Dr. Niroshan Siriwardena, University of Lincoln, United Kingdom with coauthors Stella Gwini and Carol Coupland, wrote:
"Our findings reinforce current recommendations for annual influenza vaccination of target groups, with a potential added benefit for prevention of acute myocardial infarction in those without established cardiovascular disease. This benefit may lead to an increase in suboptimal rates of vaccination, particularly among younger patients."
The researchers said they adjusted for the fact that a higher percentage of people with risk factors, such as heart attacks get vaccinated every year.
f further studies have similar findings, clinicians may have to re-thing the recommended indications and timing of vaccinations, the authors added.
The authors wrote (in conclusion):
"Influenza vaccination but not pneumococcal vaccination is associated with a reduced rate of first acute myocardial infarction. This association and the potential benefit of early seasonal vaccination need to be considered in future experimental studies."