Oct 24, 2023

Researchers explore possible reasons for high rate of sudden cardiac arrest in Black male athletes

Researchers from the National Heart, Lung, and Blood Institute (NHLBI) are exploring the high rate of sudden cardiac arrest in Black male athletes.

Recent incidents have spurred calls from some schools and medical societies for improved cardiac safety measures in sports, including greater use of emergency action plans, more CPR training, and wider availability and use of defibrillators.

Others are calling for increased screening and physicals of at-risk athletes, despite limited data on the exact causes.

A recent report from NHLBI.NIH.gov gave a summary of the researchers’ explorations with added context. Below is an excerpt from the NHLBI.NIH.gov report.

The recent sudden cardiac arrests of college basketball player Bronny James and professional football player Damar Hamlin did more than shock the sports world and the nation. They brought attention to a disturbing, but little-known, fact: Sudden cardiac arrest is the number one medical cause of sudden death in young athletes in the United States and Black athletes appear to be at higher risk.

The problem is no one knows exactly why.

In the case of James and Hamlin, quick emergency efforts saved their lives. Hamlin has recently resumed playing football and James is expected to return to the basketball court soon. But happy endings are not always the case, and some researchers are sounding the alarm.

“Understanding why among all athletes, Black players have higher rates of sudden cardiac arrest is an important public health issue and should be an urgent focus of future research,” said Jonathan Kim, M.D., director of sports cardiology and associate professor of medicine at Emory University in Atlanta. He is also current chair of the American College of Cardiology’s Sports and Exercise Cardiology Council.

Kim, who conducts health disparities research, is doing his part. He’s among several researchers supported by the NHLBI who are studying the cardiac health of athletes and others, with an eye on better understanding why these incidents of sudden cardiac arrest, though relatively rare, occur.

Young Black male college basketball players are particularly at risk. A 2020 study in the British Medical Journal found that these players had an incidence of sudden cardiac arrest or death 21 times higher than the average among high school male athletes of all races. The second highest at-risk group in the study were Black male college football players.

Researchers have offered few explanations. One condition that has been linked to sudden cardiac arrest in athletes is hypertrophic cardiomyopathy, which causes the heart muscle to become larger and thicker than normal. The condition can be inherited or acquired. It has an estimated prevalence in the general U.S. population of 1 in 500, and in athletes about 1 in 2,000. Kim points out, however, that the condition has not been shown to be more prevalent in Black athletes.

“We must also consider and assess for possible social and environmental determinants of health that affect these disparities in young athletes,” Kim said.

His own research, for example, found that Black college football players may have an elevated risk of developing a heart change called concentric left ventricular hypertrophy or C-LVH, that causes the left side of the heart to become more thickened. Kim further showed that this condition is closely linked to lower family income levels among Black players compared to White players. More studies are needed, he said.

To read the full study from NHLBI.NIH.gov, click here.