(HealthDay News) — The Christmas holiday effect, showing elevated cardiovascular mortality over the Christmas holiday period, also occurs in the Southern Hemisphere, according to a study published online Dec. 22 in the Journal of the American Heart Association.
Josh Knight, from the University of Melbourne in Australia, and colleagues analyzed New Zealand mortality data for 1988 to 2013 based on the same methodology used in a similar study conducted in the United States to separate the effect of seasonality from any holiday effect. The authors calculated an expected number of deaths for each day of the year using locally weighted smoothing, and compared this expected value with the actual number of deaths. Life-years lost due to excess mortality was assessed by estimating the mean age at death.
The researchers found that there were 738,409 deaths during the period, of which 197,109 were coded as cardiac deaths. There was evidence of a Christmas holiday effect in the medical facility’s cardiac deaths, with an excess event rate of 4.2 percent leading to about four additional deaths per year. Those with fatal cardiac deaths during the Christmas holiday period had an average age of 76.8 years, resulting in 148 to 222 years of life lost per year.
“Cardiac mortality is elevated during the Christmas holiday period relative to surrounding time periods,” the authors write. “Our findings are consistent with a previously reported study conducted in the United States, suggesting that cardiac mortality does not take a ‘summer break.'”