Colds Up Risk of Heart Attack

A cold can make your head ache--and maybe your heart too. The odds of suffering a heart attack skyrocket for cold and flu victims, researchers report in tomorrow's Lancet.

For decades, public health experts have noticed that wintertime cold and flu epidemics are often followed by a rash of heart attacks. But the link between infections and infarctions attracted relatively little attention until the 1980s, when a few studies suggested that respiratory tract illnesses might trigger heart attacks by promoting blood clots or heart-muscle inflammation.

Now, in the largest study of its kind, Christoph Meier and colleagues at the Boston University Medical Center in Lexington, Massachusetts, have found that the odds of a heart attack can almost triple after a respiratory infection. Meier's team compared the medical records of 1922 British heart patients with 7649 randomly selected controls. They found that patients with a respiratory tract infection were 2.7 times more likely to have a heart attack within 10 days of getting sick than were the controls. The link weakened over time: After 16 days, a respiratory illness did not increase the risk of heart attack.

The findings should "ring a warning bell" for physicians and heart patients, says David Spodick, a cardiologist at St. Vincent Hospital and the University of Massachusetts, Worcester, who published similar studies in the 1980s. But he and Meier agree that it is too early to base specific treatments on the discoveries. Meier, for instance, cautions that his study could not determine whether bacterial or viral infections posed greater risks. Until studies resolve this and other issues, he warns, the findings "should not be used to justify the wider use of antibiotics."