It's the grimmest of holiday statistics: Heart-attack deaths peak on three days of the year, and one of them is Christmas. The other two are the day after Christmas and New Year's Day.
Talk about your lump of coal.
And it gets worse. The holiday peak is just part of a larger, well-established pattern: More people die of heart attacks in winter than at any other time of year. In other words: It's truly the season to know your risks -- and reduce them, if you can. But first, it may help to ponder why these days are so deadly.
The seasonal link
In the USA, cardiac deaths peak in December and January, says Robert Kloner, a cardiologist at Good Samaritan Hospital in Los Angeles. In Australia, he says, they peak in July -- winter there.
So there's something about winter. But what?
"Nobody knows," says David Phillips, a sociologist at the University of California-San Diego who studies death patterns. Flu and pneumonia, which are tough on people with heart disease, clearly play roles in the high rate of all natural deaths in the winter, he says.
Shorter, darker days might matter, too, says Kloner, who has studied the winter link.
But he is convinced that one big factor is cold itself -- though the heart death spike shows up even in warmer states. "It's still colder in the winter," he says. "Even in Los Angeles, (in early December) the temperatures in the morning were in the 30s."
Cold alone, he says, can make blood vessels constrict, blood pressure rise and the heart work harder. It also might trigger changes in the blood that produce clotting and inflammation.
Just walking outside and taking an icy breath can "create a crisis," says American Heart Association spokeswoman Tracy Stevens, a cardiologist at Saint Luke's Health System in Kansas City, Mo. "That sudden exposure can cause constriction of the coronary arteries or lung constriction, which creates shortness of breath and puts a strain on the heart."
But the answer isn't staying on your couch. Stevens suspects that the sedentary lives many people lead in winter contribute to the risk. "Many of us are just like bears hibernating," she says.
And what about snow shoveling? In many areas, it might be a factor. One recent study found that 7% of winter heart-attack victims in one Canadian hospital had been shoveling snow.
Then there's Christmas. David John, an emergency-room physician for 20 years, can't say that he has noticed the holiday death surge, which was first documented in a 30-year study led by Phillips and published in 2004. But one explanation rings true to him: People feeling sick around Christmas or New Year's may put off getting help -- and end up dead.
A final suspect: Holiday stress
"People are in denial," says John, who works at Johnson Memorial Medical Center in Stafford Springs, Conn. "They don't want to spoil Christmas dinner by going to the hospital." They also might forget to take medications and may be away from their usual doctors and pharmacies, he notes.
Phillips says he also suspects that heart-attack victims arrive at hospitals that are more poorly staffed. But John rejects that idea: Senior staffers in emergency medicine "still work nights, still work weekends and still work holidays."
One theory Kloner once favored: It's all the rich holiday food and drink. But he rejected that after studying Super Bowl Sundays in Los Angeles and finding no heart-attack spike (except for one year when the Rams played and lost). Gluttony is still unwise, he adds: Salt and alcohol can raise blood pressure, fatty foods can boost cholesterol, and even one rich meal can adversely affect blood vessels.
That leaves at least one more suspect, Kloner says: "The stress. Facing relatives, buying gifts, trying to find a parking space in a busy mall."
And now add one more stressor: Worrying about having a holiday heart attack.
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