Running: Physiologically SpeakingMarathon Deaths – Why The Men?

Late last night, while soaking my feet and licking my wounds after 18 grueling miles in the cold, wind, and rain – my last long run before the NYC Marathon – I came across some disturbing news with an interesting followup question posted on the NY Flyers running forum that left me a bit shocked, a little intrigued, and slightly apprehensive about racing 26.2 miles in a couple of weeks. Apparently, at the Detroit Marathon yesterday, three men, ages 26, 36, and 65, collapsed and died for no apparent reason (other than the fact that they were running a half marathon). No doubt this is indeed sad news for all of us who are passionate about the sport and thoughts and prayers go out to the families of those who were personally affected by this tragedy, but one general question that my fellow club member and I share in response to these untimely deaths is this: Why are they all men? In other words, are men more susceptible to dying in half/full marathons than women? Is this mere coincidence or is there some scientific justification for these unfortunate events? (For the rest of this discussion, for simplification, I will refer to them as marathoners and the incidents as marathon deaths even if their unfortunate passing occurred on or around the half marathon course.)

In the spirit of raising public awareness and reminding myself as well as the running community about the inherent danger of endurance running, I will use this edition of Running: Physiologically Speaking to discuss why marathon deaths occur predominantly in men (and not in women). Hopefully, this will be somewhat educational for everyone involved.

Before I begin, I would like to throw out a couple of disclaimers.

1. The death of a runner in the middle or right after a half or full marathon is an exceedingly rare event. Estimates vary but it is reported that 0.8 deaths occur per 100,000 runners. Considering that even the most popular marathons (like New York) do not exceed 40,000 participants, to have three people die in a single race is infinitely rare.

2. Just because you are young, not male, or can run five minute miles does not mean you are without risk. There are many exceptions to the rule and not everything I will explain later pertains to everyone. So check with your own personal doctor to review your own individual risk factors before training for or participating in any endurance event. Likewise do not use anything I write as medical advice because it is not intended as such. You have all been forewarned.

Now that we’ve dealt with the pleasantries, let’s delve into a discussion of why it is so much more likely to read and hear about men dying in marathons than women. I will make some general statements about marathon runners using statistics gathered from the runners of the Detroit Marathon to illustrate my point. To make my arguments valid, two basic assumptions have to be made. The first is that marathon deaths are cardiovascular in nature or result from an acute coronary or cardiac event. Historically, cardiac problems are the most common identifiable cause of sudden death in marathon runners. Recently, it has also been recognized that troponin and other cardiac enzymes that represent myocardial injury are elevated during and immediately after a marathon (link). For the purposes of this discussion, we will ignore deaths that result from other causes. The other assumption we have to make is that the runners who ran and finished the Detroit Marathon is somewhat representative of marathon runners in general. As you will see from the data, although the numbers are small in comparison to other major marathons, the actual breakdown in percentages and established trends are not that significantly different.

Here is the chart showing the breakdown of all the finishers of the 2009 Detroit Marathon by age and sex.

Fact #1 – The most populous age group was men between 40-44 and women between 25-29. In general, older men and younger women represent the majority of marathoners. Whatever your theories are for why this is true, this trend is typical of most long distance races.

Fact #2 – Older men are statistically more at risk for major cardiovascular events than women. According to the Heart Disease & Stroke Statistics published by the American Heart Association, which you can read here, the average annual rates of first major cardiovascular events rise from 3 per 1000 men at ages 35-44 to 74 per 1000 at ages 85-94. For women, comparable rates occur 10 years later in life. The gap narrows with advancing age. Likewise, if you look at a representative graph of heart attack hospitalizations in New York State in 2000-2005, as depicted here, you can appreciate the fact that acute cardiac events start early and occur more frequently in men. (Although these statistics do not pertain specifically to athletes, I am using the data to illustrate a general trend so the actual numbers is not particularly significant in this discussion...)

Fact #3 – Women, compared to men, are very unlikely to suffer acute cardiac events until after menopause. This epidemiologic observation can be explained by the fact that physiologic estrogen has been proven to be cardioprotective. That is the reason why, as we saw in the Heart Disease & Stroke Statistics, cardiovascular risk do not rise substantially in women until beyond the age of 44. This cardioprotective property of estrogen is one of the reasons why hormone replacement therapy should be considered for most postmenopausal women.

So now, if we go back and revisit the demographic data gathered from finishers of the Detroit Marathon, we see something interesting. Notice how the majority of male marathon runners are above the age of 35 when the risk of acute cardiac events becomes substantial and begins to rise. However, when we look at the corresponding female runners, the majority of them are below the age of 40 or 45, which is the age cutoff when their risk of acute cardiac events rises. This means, essentially, that the men who most commonly run marathons are also the most at risk to suffer an acute cardiac event while the women who most commonly run marathons are much younger and have much lower risk. No wonder why you hardly ever hear of women collapsing and dying during marathons. It just doesn’t happen, as proven by the statistics and explained by medical science. (*I realize that the 29-year-old man who died during the Detroit Marathon is outside the range of appreciable risk for men, but I'm treating this case as exception to the rule...)

But even beyond these reasons, I can think of two other possible explanations for the disparity of mortality rates between male and female marathoners. One is the simple fact that men in general (and I include myself in this) do not care as much or pay as close attention to their health as their female counterparts. Study after study have shown that men visit doctors less frequently, engage in fewer preventive practices, and are less knowledgeable about their own medical history than their female counterparts. It is not surprising then that more men in general die younger and have a shorter life span than women. The importance of screening tests and regular scheduled visits to your doctor cannot be overemphasized, whether you are a veteran marathon runner or not.

Finally, I think the false bravado of the general male ego may also contribute at times to our own demise. Consider the newbie runner who thinks he can run a marathon without having run farther than a few miles in training. He is probably carrying a Y chromosome. Or the runner who is at mile 21, slogging on, refusing to acknowledge the sharp stabbing pain in his chest that is growing more intense with every step. He is also likely to take his bathroom break standing up. Finally, there is the runner who just finished the marathon and is getting congratulated left and right by friends and family. He feels tremendous pressure on his left chest with pain radiating down his left arm. How likely would this person be to voice concern if he were male vs if she were female?

In conclusion, you may ask, “Is there a take home message to all of this?” I think the most important message I want to leave you with is not to assume that you are healthy and well just because you train for and run marathons. Running does not automatically give you the right to ignore your health. Be knowledgeable. Visit your doctor and find out what risk factors you have and discuss your concerns with him/her so you can be an active participant in your own care. Because, outside of psychic powers or a fortune teller who can predict the future with 100% accuracy, taking control of your own health and well-being is the best guarantee you have to living a long, productive and healthy life – on and off the marathon course.

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As a reminder, I am still missing a few questions to complete my list of 20 Questions about Me…so please feel free to ask away (even if you have already asked a question!). You can drop them in here or in the comments to the last post. I’ll start providing answers in the next post. Thanks for playing.