The flu vaccine may reduce by half the risk of heart attacks in some middle aged people, according to new research.  

Researchers in Australia looked at 559 patients over 40 who were referred to a major hospital during consecutive winters between 2008 and 2010 - 275 of these patients had suffered a heart attack and 284 had not.

Tests on the participants showed that one in eight of the heart attack patients had recently had flu, compared to 7% in the group of non-heart attack patients. One in two of all the patients in the study had had the flu vaccine that year.

Flu had not been diagnosed in one in 10 patients who had had flu, indicating, according to the researchers, that it may be missed in hospital patients with other medical problems.

It was found that a recent respiratory infection was more common among those patients who had had a heart attack and doubled the risk of getting one. 

However, after taking into account factors such as age, smoking status and cholesterol levels, the researchers found that having the flu did not increase heart attack risk,contrary to the findings of previous research.

However, getting the flu jab may actually protect against having a heart attack, reducing the risk of having one by 45%, they propose in the research paper.

The researchers say the findings indicate that 50 to 64-year-olds would specifically benefit from the flu vaccine in terms of heart health, and should be included in national vaccine schedules.

At present, the HSE specifically, recommends the yearly flu vaccine for people over 65, those with particular medical conditions, obese people, pregnant women, nursing home residents, and healthcare workers and carers.

The research, carried out at the University of New South Wales in Sydney, is published in the journal Heart.

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