Flu Doubles Risk of Heart Attack and Stroke

More than 15 million flu jabs will be given to elderly and vulnerable patients in the next two months

A bout of flu doubles the immediate risk of having a heart attack or stroke, a groundbreaking study has found.

Sufferers are four times more likely to be affected within three days of falling ill with the flu and are at double the risk for up to a week, according to the study of two million people.

Flu dislodges fatty deposits that build up in the arteries, leaving them free to move around the body and get stuck in the brain or heart, where they block the blood flow.

Researchers describe the increased risks associated with flu as a "substantial public health problem" that is killing thousands of elderly people every year. The risks also apply to other serious respiratory infections, such as bronchitis and pneumonia.

Around 23,000 more people die in winter than in the summer months.

Prof Tom Meade, the co-author of today's study, said heart attacks and strokes brought on by flu and other respiratory infections would account for "several thousand" of these deaths.

More than 15 million flu jabs will be given to elderly and vulnerable patients in the next two months. Prof Meade, from the London School of Hygiene and Tropical Medicine, is calling for as many as possible to have the vaccine to guard against the risks.

Prof Meade stressed that the risks did not apply to colds, only serious bouts of flu or other infections such as bronchitis which were severe enough for patients to see their GP.

Dr Tim Clayton, the lead author of the report, said the results suggested that putting more effort into preventing infection through vaccination and treating diseases sooner could save many lives. He said: "Since there may be a large number of vascular deaths attributable to respiratory infection … the benefits of reducing respiratory infection particularly in the winter months could be substantial."

Around one in three heart attacks and strokes is fatal.

The study, published online today in the European Heart Journal, was funded by the British Heart Foundation.

Its spokesman, Dr Mike Knapton, said: "We recommend that anyone with heart disease has the flu jab."

Joe Korner, of The Stroke Association, said it was "vital" that anyone at high risk of stroke or other cardiovascular conditions had the vaccine.

Of the two million people whose GP records were studied, 11,000 had suffered a heart attack. They were twice as likely to have been diagnosed with flu or a respiratory infection in the previous month.

Around 9,000 had suffered strokes. They were twice as likely to have been diagnosed with a respiratory infection in the previous three days. The risk tailed off with time and three months after being diagnosed with flu, patients were at only slightly increased risk.

The winter flu season usually starts in December or January and lasts up to two months. Vaccines are available on the NHS for the over-65s and for patients with certain illnesses, such as asthma.

The UK has not suffered a seasonal flu epidemic in seven years. However, experts warn that one is due.

By Nic Fleming, Dec 2007
UK Daily Telegraphy Medical Correspondent

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