"Two Men Die of Apparent Heart Attacks," read the headlines covering the Philadelphia marathon this past November. Even those who pay only cursory attention to the news have heard such stories reporting deaths among long distance runners who've just completed marathons or half-marathons. Is the sport really so risky as that? No, concludes a study in the New England Journal of Medicine, featured on PodMed and our YouTube this week.
The study compiled quite a lot of data from the time period January 1, 2000 through May 31, 2010 concerning cardiac arrests that took place either during running or within a one hour window after completion of either a marathon (26.2 miles) or half-marathon (13.1 miles), as well as the sheer number of participants in such races. That would be some 10.9 million registered race participants.
A total of 59 cardiac arrests occurred, 40 of them in marathons and 19 in half marathons. Almost 90% of the arrests occurred among men, with an average age of about 42. Just over 70% of those who experienced cardiac arrest died, so the incidence of sudden cardiac death among these long distance runners was one in 259,000. As Rick opines in the podcast, that's a very low risk.
The point must be made, of course, that for those who died of sudden cardiac arrest during a long distance running event, the risk was 100%. So what do we know about those runners? Among those for whom records were available, hypertophic cardiomyopathy, an abnormal thickening of the heart muscle, felled the majority. Most of the remainder, who were also a bit older on average, had obstructions in their coronary arteries, and there was a smattering of other cardiac conditions.
How about the survivors, those who suffered an apparent cardiac arrest but did not die? Those folks received the benefit of bystander administered CPR, offering us yet again another reason to encourage people who witness an apparent heart attack to step in and attempt CPR. We editorialize, predictably, that now that it's just chest compressions there's almost no good reason NOT to try it, and data like this make the case even more compelling. And it appears that those who survived were those with coronary artery blockages, not those with hypertrophic cardiomyopathy.
The authors compare deaths in this cohort to sudden death among collegiate athletes at about 1 in 44,000, or previously healthy joggers (1 in about 7600) and conclude that while clearly grabbing the headlines, deaths among those who compete in long distance running are fairly rare. Since so many more people have taken up running during the study period, it seems likely that we may be seeing more sensationalist news reports about sudden cardiac death while the individual risk appears to remain the same.
Other topics this week include lung function and marijuana smoking and how dementia impacts hospitalizations, both in JAMA, and an online release from Archives of Internal Medicine on the potential dangers of dabigatran. Until next week, y'all live well.