Risk for MI increases during Christmas holiday
Christmas and the Midsummer holiday in Sweden were linked to an increased risk for MI, specifically in patients who were older and sicker, according to a study published in BMJ.
Moman A. Mohammad, doctoral student of cardiology at Lund University in Sweden, and colleagues analyzed data from 283,014 patients (mean age, 72 years; 64% men) from the SWEDEHEART registry who had an MI between 1998 and 2013. Data from the registry included the date and time of symptom onset to the nearest minute.
Researchers identified all MIs with symptom onset during Christmas and New Year’s, Easter, the Midsummer holiday, Fédération Internationale de Football Association (FIFA) World Cup tournaments, Union of European Football Association European Championship tournaments, and winter and summer Olympic Games. The control period was 2 weeks before and after holidays and 1 year before and after tournaments.
The primary outcome of interest was the daily count of MI.
The overall risk for MI increased by 15% during the Christmas and New Year’s holidays (incidence rate ratio [IRR] = 1.15; 95% CI, 1.12-1.19). Compared with other holidays, the risk for MI was higher on Christmas Eve (IRR = 1.37; 95% CI, 1.29-1.46).
This increased risk was also seen during Midsummer holiday (IRR = 1.12; 95% CI, 1.07-1.18). The risk for MI was not increased during the Easter holiday and sports events. There was a trend for an increased risk for MI in men during the Summer Olympics, but it did not reach statistical significance after adjustment.
There was a circaseptan and circadian variation in the risk for MI, with an increased risk on Mondays and around 8 a.m.
“Our results showed a consistently higher risk of myocardial infarction mainly due to higher rates of [non-]STEMI and a greater number of patients who were elderly, had diabetes, a history of coronary artery disease or were already taking other medication,” Mohammad and colleagues wrote. “This indicates that the ‘vulnerable patient,’ who may have risk factors such as blood vulnerable to thrombosis and myocardium vulnerable to arrhythmias in addition to vulnerable plaques, may be more prone to these precipitators of disease.” – by Darlene Dobkowski
Disclosures: The authors report no relevant financial disclosures.