Why more heart-related deaths happen around the holidays

Heart related deaths tend to increase around the holidays, and the cold weather may not really be the reason for these fatalities, a new study suggests.

From 1988 to 2013, researchers examined data on more than 738,000 deaths in New Zealand to rule out the likely influence of cold temperatures, where Christmas comes during summer. Overall, about 197,000 of these fatalities were heart-related.

During the period of Christmas and New year’s Eve which ranges from the last week of December to and the first week of January, heart-related issues caused 4.2 percent more deaths outside of the hospital than would be expected if the holidays didn’t affect the death rate, the study found.

An extra four deaths per year are attributable to the holidays. Comparing the average age at the time of death, the fatalities during the season of holidays have slightly younger age 76.2 than 77.1 during other times of year.

“This strongly suggests that the Christmas effect isn’t caused by temperature or anything related to the winter season,” said lead study author Dr. John Knight of the University of Melbourne in Australia.

“When temperature is removed as a likely cause that leaves a reasonably small pool of established social, health and health-system-related risk factors,” Knight added.

Previous research published in the Journal of American Heart Association has noted a rise in deaths during the holiday season in the United States, where Christmas tends to fall during the coldest time of year and death rates are already seasonally high due to influenza.

Current study investigates the death trends in New Zealand, where cardiac death rates tend to be lowest during the summer time in general.

The study does not suggest that holidays or weather directly cause a spike in deaths or heart-related fatalities, the authors note.

New Zealand has an island climate without harsh cold and hot weather swings which have been associated with cardiac deaths in other studies allowing researchers to separate any winter effect from holidays effect.

The researchers speculate a number of factors responsible for rise in heart-related deaths during the holidays season including seasonal stress, changes in diet and alcohol consumption or lower staffing at hospitals.

Some of the rise in heart-related deaths around holidays can be attributed to people put off needed care during this time of the year or they cannot get treatment for acute illness because they are travelling away from home, the researchers also point out.

Some terminally ill patients also may manage to hold off dying until just after they get through one last Christmas with friends or loved ones, the authors conclude.

Other research has noted a link between excessive drinking and a greater likelihood that people will develop or need treatment for heart problems, said Dr. Tim Stockwell, a researcher at the University of Victoria in British Columbia who wasn’t involved in the study.

“Many other factors have been speculated about as contributing to the phenomenon of more cardiac deaths at holiday periods, e.g. more respiratory infections because of cold weather at Christmas time, less accessibility to health care, increased stress,” Stockwell told.

“This new study is able to rule out the cold weather hypothesis as the sole cause since the study looked at the Christmas holiday in New Zealand which falls in the summer,” Stockwell added. “There was some support for the theory that there is less access to healthcare during the holiday due to the effect being more pronounced for deaths occurring outside of hospital, and increased emotional stress, dietary changes and additional stress are also consistent with the observed results.”