‘Tis the season of the year when people can look forward to gifts, carols, tinsel-wrapped trees, candlelight services, family togetherness and … keeling over with a coronary. That last fact was found in a bag of coal left under the tree by Swedish researchers. Their data suggest that the holiday ought to carry a prominent warning label from the surgeon general.

The scientists were involved in a study known as, believe it or not, SWEDEHEART — a droll acronym for “Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies.” Their survey of 283,014 heart attacks recorded in Sweden between 1998 and 2013 led them to the unavoidable conclusion: Celebrating this festive occasion can be fatal.

The risk of a myocardial infarction rises by 37 percent on Christmas Eve, peaking at 10 p.m. — just about the time frazzled parents and grandparents are wrapping those last presents, keeping an eye out for 5-year-old snoops and fretting about where to put the Elf on the Shelf. The heart attack rate is 29 percent higher than normal on Christmas Day — and remains elevated on Dec. 26 (Boxing Day, as it’s known in Sweden and other European countries).

We already suspected that chestnuts roasting on an open fire are no protection against sudden death. A 2004 study in the medical journal Circulation found that deaths from heart attacks showed a regular increase “starting around Thanksgiving, climbing through Christmas, peaking on New Year’s Day.”

You might suspect cold weather and snow shoveling are to blame, but no: The 2004 study focused on Los Angeles County, where the average daily low in December is a frost-free 51 degrees. The same hazard has been detected in New Zealand, where St. Nick could make his rounds in shorts and sandals.

Nor is this phenomenon the norm on all holidays: The scientists found no spike in coronary fatalities on New Year’s Eve or Easter. There was, however, a heightened danger on Midsummer, a June holiday observed in Sweden. But its observance involves dancing around a maypole, eating herring and drinking shots of akvavit, all of which sound like asking for trouble.

It’s conceivable that eggnog is the precipitating factor in the Christmas season. But the high-risk days just happen to coincide with the times when people are most likely to be suffocated — sorry, surrounded — by relatives, including Uncle Melvin and his new girlfriend. While family get-togethers can mean hearts overflowing with warmth and gratitude, they can also means hearts pounding from aggravation and angst.

The vast majority of us, though, will survive the experience. And here’s some solace if you have to trek to the mall to stand in line to exchange an ugly sweater after the festivities are done: Not everyone lives so long.

Editorial by the Chicago Tribune

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