Race and position may be factors in football player heart risks

"We believe high blood pressure, weight gain, and now race may all be a part of this risk calculus for acquired concentric left ventricular hypertrophy," says Jonathan Kim. "While underlying mechanisms may be biological, we must also assess for possible social and environmental determinants of health that affect these race-based differences." (Credit: Jamie Sabau/Getty Images)

New research suggests some college football players may be at risk of developing heart-related complications, based on race, the position they play, their weight, and blood pressure.

The specific heart-related complication, called concentric left ventricular hypertrophy or C-LVH, involves enlargement and thickening of the walls of the heart’s main pumping chamber, the left ventricle. With this condition, in the general population, there is increased risk of later-life cardiovascular disease.

For the new study, researchers recruited and studied 300 college football players from two National Collegiate Athletic Association (NCAA) Division-I football programs between 2014 and 2019. They reviewed clinical data including body weight and blood pressure, echocardiography (images of the heart), and vascular measurements at multiple timepoints throughout the study period. Researchers also analyzed demographics and family income.

“We found that both self-identified Black and white football linemen—which include players at the tackle, guard, center, or defensive end positions—similarly developed concentric left ventricular hypertrophy,” says Jonathan Kim, associate professor of medicine, division of cardiology at Emory University School of Medicine and chief of sports cardiology for Emory Healthcare.

“However, for non-linemen—which include quarterbacks, running backs, wide receivers, tight ends, kickers, punters, and others—a higher percentage of Black collegiate football players were more likely to develop concentric left ventricular hypertrophy than white football players. This leads us to think more about why Black race is associated with acquired C-LVH,” explains Kim, the paper’s senior author.

In the linemen analysis, progression in acquired C-LVH was similar between Black and white athletes: post-season year one (Black: 6%, white: 12%); post-season year two (Black: 20%, white: 16%); and post-season year three (Black: 14%, white: 38%). At baseline, white athletes were taller, heavier, and more commonly held linemen positions.

When looking at non-linemen, the development of C-LVH was increased in Black players: post-season year one (Black: 16%, white: 3%); post-season year two (Black: 18%, white: 6%); and post-season year three (Black: 24%, white: 8%). The researchers note in the publication that non-linemen were generally considered less likely to develop C-LVH.

While it is known that sport-specific exercise training can lead to changes in the heart, often referred to as “athlete’s heart,” in football players who gain significant weight (particularly linemen) or develop hypertension, there is increased risk of developing C-LVH, which does not appear to be an adaptive training-related response.

“We believe high blood pressure, weight gain, and now race may all be a part of this risk calculus for acquired concentric left ventricular hypertrophy,” says Kim. “While underlying mechanisms may be biological, we must also assess for possible social and environmental determinants of health that affect these race-based differences.”

The researchers looked at median household income based on individual hometown zip codes and US census data and found the average median neighborhood family income was lower for Black versus white college football athletes ($54,199 versus $63,146). More research will be needed in this area to connect social determinants to athletes with concentric left ventricular hypertrophy, the study notes.

“Our findings add further depth to our understanding of established cardiovascular risk factors observed in college football players, and now which players may be at greatest risk of developing concentric left ventricular hypertrophy,” says Kim.

“We also know there is increased risk for adverse cardiac outcomes among retired professional football linemen. By identifying college football players earlier who could develop early heart disease, regardless of race, we feel we can improve cardiac prevention strategies and counseling for these young athletes as they ultimately transition away from competitive football.”

The study appears in the British Journal of Sports Medicine. The National Institutes of Health/National Heart, Lung and Blood Institute funded the work.

Source: Emory University