A new study published in the journal Circulation: Cardiovascular Imaging found that former National Football League (NFL) players have significantly enlarged aorta than the others in general population. But researchers said they are not sure that whether the condition poses the risk of life-threatening aneurysms to the former players.

The Dallas Heart Study researchers said that even after adjusting the data based on certain factors that affect the size of the aorta, they could conclude that former NFL players were twice as likely to have larger aortas.

The corresponding author Dr. Parag Joshi, Assistant Professor of Internal Medicine, said, but what remains unclear is whether the same risk especially applies to NFL players as a dilated or enlarged aorta does for the general population. “Is this a normal adaptation from having trained at the elite level throughout their youth, or is this a bad adaptation that puts them more at risk for problems?”

The researchers found that former linemen had larger aortas than the non-linemen. It shows that increased aortic diameter is an adaptation to the demands placed on a player's heart during his career, said Dr. James de Lemos, Medical Director for the Dallas Heart Study.

According to the Dallas Heart Study – a population-based study designed to find new genetic, protein, and imaging biomarkers that could identify early cardiovascular risk, around 30% of the former NFL players and less than 9% of people in the control group had enlarged aortas.

The study was led by researchers from Cleveland Clinic, in collaboration with colleagues of UT Southwestern, Johns Hopkins Medicine, and MedStar Sports Medicine. It suggests the clinicians consider if a patient with a more extensive aorta has a history of long-standing athletic activity and calls for further study into what risks the enlarged aortas pose for those athletes.

The researchers compared the size of ascending aortas, using an innovative imaging technique. The patients with enlarged aortas over 40 millimeters in diameter are at higher risk of life-threatening tears, noted Dr. Joshi.

According to the previous study, the active elite athlete had larger aortas, but the size was still within the normal range, Dr. Joshi said.

A human aorta tends to become larger with age, so the former NFL players might have developed larger aortas while playing, and it has been enlarged further as their age increased.