Science series: Is it possible to prevent sudden death?

I noticed that there are certain topics that keep coming up time and time again amongst runners online. Most of these issues are already answered by science, but many runners out there just don’t have the time to research a topic or don’t know where to look. So, I thought I’d answer a few of these questions on my blog.

One of these issues is the use of medical certificates for running events. Some countries require you to have a signed medical certificate before you can participate in a sporting event (so not only running). In France and Italy it’s required by law, but there are also lots of countries where it generally isn’t required, such as the USA, the Netherlands and the UK. Many runners believe that a mandatory medical certificate would bring down the number of sudden deaths during running events, but is that actually the case?

So, what is sudden death? It’s also known as sudden cardiac death and is most common among young athletes (generally under 35, although this doesn’t mean you’re safe when you’re over 35 years of age). It is an unexpected death due to cardiac issues within roughly one hour of the onset of the symptoms.

How common is sudden cardiac death? The estimate is that it happens to 1 in 80,000 athletes. You’ve probably seen or heard reports online of sudden deaths happening at big running events.

Are you at risk? There are a few causes of sudden cardiac death, the most common of which are hypertrophic cardiomyopathy, anomalies of coronary arteries, Marfan’s syndrome and arrhythmogenic right ventricular cardiomyopathy. Another big warning sign is if someone in your family has suddenly died at a young age. And what if you’re over 35? Sudden cardiac death can still happen to those over 35, but for this group the cause is often different than for those under 35. In this age category it’s most often due to atherosclerotic coronary artery disease.

The problem with sudden death is that athletes are often unaware of their condition and often the first symptom they present with is the sudden cardiac death, which makes it harder to prevent. So, does screening help? In some cases, yes, it does. It depends on how elaborate the screening is. A ECG at rest obviously doesn’t tell you as much as an ECG while exercising. And an ECG is good for detecting things like cardiomyopathies, but it isn’t accurate when it comes to detecting coronary artery disease.

Does a mandatory medical certificate help bring down the number of sudden deaths? No, not really. The rates of sudden death in the USA (where a signed medical certificate is not mandatory) versus those in Italy (where pre-screening is required) are basically the same. Meaning that screening currently isn’t accurate enough. Just recently a Dutch lawyer died while doing a triathlon in Italy, showing that pre-screening unfortunately isn’t a guarantee.

Every time someone dies at a big sporting event in a country where pre-screening isn’t mandatory, there are always people who say: “We should make pre-screening mandatory, then this wouldn’t have happened”. Italy and France are actually a good example of why this statement isn’t true. Unfortunately, there are still people who have been screened and still experience cardiac issues during sporting events in these countries.

So, should you get tested? Of course you should! Getting tested really can’t hurt! It might not be able to detect all causes of sudden death and therefore not be a 100% guarantee (but let’s be honest, there are very few things in life that have a 100% guarantee anyway), but it can detect some. I get tested every year. My only point is that these pieces of paper that you need to get signed before you can participate in a sporting event in Italy and France don’t work. They don’t prevent enough, they are basically just disclaimers, but doctors don’t like signing them, just in case something happens and they are held responsible. My point is that we should get rid of these pieces of paper, since it’s a lot of hassle for everyone involved, but you should still get tested on a regular basis.

Sources:

D. Corrado, A. Zorzi, Sudden death in athletes, Int J Cardiol (2017), http://dx.doi.org/10.1016/j.ijcard.2017.03.034

D. Corrado, C. Schmied, C. Basso, et al., Risk of sports: do we need a pre-participation screening for competitive and leisure athletes? Eur. Heart J. 32 (2011) 934–944.

A. Halkin et al., Preventing Sudden Death of Athletes With Electrocardiographic Screening: What Is the Absolute Benefit and How Much Will it Cost?, Journal of the American College of Cardiology, Vol. 60, No. 22 (2012), 2271-2276

Runner’s World – Can you prevent “sudden death”?