Racial differences in athletes’ hearts

It’s going to be a summer of sports. The European Football Championships have started. So have the NBA play offs. And there are the Olympics Games in Beijing to look forward to.

Athletes are known for having stronger hearts than ordinary mortals like you and me. However, a recent study shows that among athletes, heart structure and function may significantly differ - depending on skin color and ethnicity.

A study of about 2000 athletes conducted at the National Football League (NFL) Invitational Camp from 2000 to 2005 showed that black football players have double the likelihood of having electrocardiograms (ECGs) that do not follow the norm. The problem is whether these “abnormal” readings should also be considered as “unhealthy.” Researchers however, believe that

“the criteria we have always used for normality are based on data from white people, and it turns out that black and white people are not identical in this regard.”

Unfortunately, during medical check ups of athletes, the ECG readings are usually used as indication of health status.

“If you use the ECG as a screening tool, the ECG in blacks are more likely to be abnormal. That would raise the possibility of heart disease more frequently — an unbalanced situation. Black athletes are more likely to be judged incorrectly to have heart disease.”

This difference is not only restricted to football players.

In another study by British researchers, 300 leading European black athletes from different disciplines were matched with 300 white athletes in the same discipline. Their results show black athletes tend to have left ventricles which have thicker walls compared to their white counterparts. The left ventricle is chamber of the heart that pumps blood to the body. The thickening of the left ventricular walls is called left ventricular hypertrophy and is usually taken as a symptom of hypertrophic cardiomyopathy, a disease “considered to be the most common cause of exercise-related sudden death in young athletes.”

It has been thought for quite a while that there are some ethnicity-related differences in people’s hearts but it has never been proven. These studies were the first ones to show evidence that such differences does exist, at least for young athletes. These studies show that ethnic differences should be taken into consideration in pre-competition screenings.

Sources:

Magalski et al. BrowneRelation of Race to Electrocardiographic Patterns in Elite American Football Players. J. Am. Coll. Cardiol., June 10, 2008; 51: 2250 - 2255.

Basavarajaiah et al. Prevalence of Hypertrophic Cardiomyopathy in Highly Trained Athletes: Relevance to Pre-Participation Screening. Am Coll Cardiol, 2008; 51:1033-1039.

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