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Updated: Jul 8, 2026
04:57
Establishing a Competing Risk Regression Nomogram Model for Survival Data
Published on: October 23, 2020
Competing risks of mortality with marathons: retrospective analysis
Donald A Redelmeier1, J Ari Greenwald
1Department of Medicine, University of Toronto, and Sunnybrook Health Sciences Centre, Ontario, Canada M4N 3M5. dar@ices.on.ca
BMJ (Clinical Research Ed.)
|December 25, 2007
Summary
Organized marathons do not increase sudden death risk. Road closures prevent more traffic fatalities than sudden cardiac deaths occur, showing a net societal benefit for marathon running.
Area of Science:
- Public Health
- Cardiology
- Sports Medicine
Background:
- Anecdotal reports suggest marathons increase sudden cardiac death risk.
- Societal impact of organized marathons, including road closures, requires objective assessment.
Purpose of the Study:
- To compare the societal risk of sudden cardiac death in marathons versus motor vehicle crash fatalities prevented by road closures.
- To evaluate the net public health impact of organized marathons.
Main Methods:
- Retrospective, population-based analysis of marathons in the United States (1975-2004).
- Ecological comparison of sudden cardiac deaths and estimated motor vehicle fatalities prevented.
- Analysis included over 3.2 million runners and 750 marathons.
Main Results:
- 26 sudden cardiac deaths observed (0.8 per 100,000 participants).
- Estimated 46 motor vehicle fatalities prevented due to road closures (35% risk reduction).
- A net societal benefit observed, with approximately 1.8 crash deaths saved per sudden cardiac death.
Conclusions:
- Organized marathons do not increase sudden death risk from a societal viewpoint.
- The public health benefits of marathons, considering prevented traffic fatalities, outweigh cardiac risks.
- Findings counter media-driven perceptions of marathon-related mortality.
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