By Lilian Anekwe
The seasonal flu vaccination campaign could reduce heart attacks by a fifth, and leads to even greater reductions if patients are vaccinated early in the season, according to a UK study.
Researchers matched 16,000 patients in clinical at-risk groups with 62,000 controls from the UK General Practice Research Database.
52.9% of the case cohort and 51.2% of the controls had received the flu jab in the year prior to the index date.
But people who were vaccinated early in the flu season of the previous year had a lower rate of acute myocardial infarction, at 21%, than the 12% reduction seen in those who were vaccinated after mid-November.
Pneumococcal vaccination was not associated with a reduction in acute myocardial infarction rates – suggesting the reduction was not due to confounding clinical indications.
Professor Niroshan Siriwardena, a GP and professor in primary care at the University of Lincoln concluded: ‘Further research is needed to confirm early vaccination confers additional reduction in risk for acute myocardial infarction. If substantiated, this finding has implications for timely supply and administration of vaccine and could lead to changes in recommendations for timing of vaccination.'
CMAJ, online 20 SeptFlu jabs protect against heart attacks