December 22, 2007–TORONTO–Based on media reports, one might conclude that marathon runners face a high risk of sudden cardiac arrest (SCA). Not so, according to a study published in the British Medical Journal on December 22. Canadian researchers compared the risks of sudden cardiac death during a marathon run with the risk of dying in a motor vehicle accident that might have occurred if the roads had not been closed for the race.
The data came from marathons run on public roads with at least 1000 runners over the last 20 years. Of over 3.2 million runners, 26 had sudden cardiac death, equivalent to 0.8 deaths per 100,000 runners. Because of road closures, an estimated 46 accidental deaths were prevented, which is equivalent to a 35 percent reduction in relative risk of running rather than driving (or being driven). Put another way, 1.8 crash deaths were saved for every runner who dropped dead.
Researchers concluded that organized marathons are not associated with an increase in sudden deaths, contrary to anecdotal impressions fostered by news media.
BMJ 2007;335:1275-1277 (22 December)