Is There a Better Time of Day to Have a Heart Attack? This question was asked by Dr. David J. Lefer of the Department of Surgery, Division of Cardiothoracic Surgery, Emory University School of Medicine in Atlanta in a study published this February. (1)
According to Dr. Lefer, it is widely accepted that the time of the day, the day of the week, and the season of the year influence the risk of a cardiovascular episode.
For example, heart attacks occur more frequently early on Monday mornings, especially during the fall and winter months. Recent research confirms that there is also “a significant contribution of intrinsic mechanisms mediating temporal dependence of cardiovascular physiology and pathophysiology,” medspeak for “the time of day and day of the week matters a lot, no matter where you are.”
Dr. Lefer cites the example of travelers who appear to retain time-of-day oscillations if they have a sudden cardiac episode, in such a way that the peak incidence is equivalent to the early hours of the morning in their time zone of origin.
It’s Monday Morning All Over the World
A 2004 study at Tokyo Women’s Medical University showed that many workers suffer a significant increase in blood pressure as they return to the office after the weekend. They also have more heart attacks in the early hours of Monday morning. (2)
A 2009 research study in Italy confirms that heart attack events are not randomly distributed over time but show specific time patterns of occurrence. It also uncovers that transient ischemic attacks (TIAs) are most frequent in the fall and winter, and less common in spring and summer, with the highest number of cases in October and the lowest in February. And, as expected, they are most frequent on Monday! (3)
Strike and Steptoe’s 2005 research in the UK on behavioral and emotional triggers of acute coronary syndromes reviewed the evidence in published literature from 1970 to 2004. Their findings revealed that there is a greater risk of acute TIAs in the winter months, and from other information about the timing of these episodes, a Monday morning in the winter is among the most lethal times for an event such as this to take place. (4)
Eastern Europeans are not immune but the seasonality seems to vary slightly. Seasonal variations in the occurrence of acute myocardial infarction were studied in Hungary between 2000 and 2004. A peak period of occurrences was found during spring, while minimum number of events were recorded during summer. The weekly peak period of greater risk was found to be Monday, showing a gradually decreasing tendency throughout the week, reaching its minimum risk level on Sunday. (5)
Need more evidence? A meta-analysis of excess cardiac mortality on Mondays was conducted at the Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands in 2005. The research evidence suggests significantly greater risk on Monday compared to other days of the week. The incidence of sudden cardiac death is markedly increased on Monday, similar for men and women, and for subjects below and above 65 years of age. (6)
Next Monday, I’m staying in bed.
Lefer, D. (2010). "Is There a Better Time of Day to Have a Heart Attack?" Circulation Research 106(3): 430.
American Journal of Hypertension 17, 1179-1183 (December 2004)
Manfredini, R., F. Manfredini, et al. (2009). "Temporal Patterns of Hospital Admissions for Transient Ischemic Attack: A Retrospective Population-based Study in the Emilia-Romagna Region of Italy." Clinical and Applied Thrombosis/Hemostasis.
Strike, P. and A. Steptoe (2005). "Behavioral and emotional triggers of acute coronary syndromes: a systematic review and critique." Psychosomatic Medicine 67(2): 179.
Kriszbacher, I., I. Boncz, et al. (2008). "Seasonal variations in the occurrence of acute myocardial infarction in Hungary between 2000 and 2004." International Journal of Cardiology 129(2): 251-254.
Witte, D., D. Grobbee, et al. (2005). "A meta-analysis of excess cardiac mortality on Monday." European Journal of Epidemiology 20(5): 401-406.