The health risks of playing football extend beyond concussions and traumatic brain injuries. In a new pair of studies, scientists are evaluating football players’ heart health, both in a group of retired professional athletes and first year college players who completed their first season of college football.
The new studies are the first to connect heart rhythm disorders with athletes from a strength-based sport; studies in the past have linked the increased risk of heart rhythm disorders to endurance athletes. Researchers are finding that structural changes in the hearts of football players could be associated with increased risk of heart rhythm disorders later in life.
A common heart rhythm disorder is atrial fibrillation (AFib), characterized by an irregular heartbeat that can lead to blood clots, stroke, heart failure, and other complications. AFib currently impacts the lives of 2.7 million Americans.
“Our findings seem to suggest that perhaps when you get to the extreme ends that we see in these elite athletes, there may be a negative impact on the heart," explained study leader Dermot Phelan, MD, PhD. "Players should not assume that leading a healthy lifestyle in terms of regular exercise means that they're immune from developing cardiac problems and, in fact, they may be at higher risk for things like atrial fibrillation."
In the first study, Phelan and other assessed the heart health of 460 former professional football players via tests like electrocardiogram and echocardiogram, blood tests, and heart history surveys. Researchers compared the results from these tests to the results of tests from non-football playing members of the public with demographic profiles similar to the football-playing study participants.
They found that the former football players were more than five times as likely to have a heart rhythm disorder compared with the control group. Researchers also observed other signs of “abnormal electrical impulses” in the hearts of former football players as well as a lower resting heart rate.
"Because they had a low resting heart rate, most of them did not get the rapid heart rate that typically warns people that they have atrial fibrillation," Phelan explained. "Most were unaware of it until our screening study. The message is that they need to get regular checkups to be sure they are maintaining a proper heart rhythm."
In the second study, researchers assessed the heart health of 136 first year college football players with similar tests. Compared to 44 first years who did not play football, the athletes exhibited structural changes in the heart, including enlargement of the aortic root, where the aorta meets the heart. Scientists aren’t sure yet what this symptom means.
"We often think of football players, like all athletes, as the picture of health, but we're gaining this body of knowledge that signals some maladaptive cardiovascular changes and potentially even early cardiac risk in some of these players," explained primary study author Jonathan Kim, MD. "It suggests we need to pay close attention to the heart health of young football players. Also, future studies will need to focus on understanding the clinical significance of our findings."