Can Running a Marathon Cause Pulmonary Edema?

A study presented at the European Respiratory Society's Annual Congress revealed that running a marathon has been linked to pulmonary edema. The researchers studied 26 people before and after a race. They found that 50 percent of the runners exhibited signs of pulmonary edema. Further research is planned to explain this connection.

Pulmonary Edema

Pulmonary edema "is an abnormal buildup of fluid" in the lungs and can lead to complete respiratory failure. Although it is often linked to congestive heart failure, this is not the only cause of the edema. Pulmonary edema can also occur because of trauma, infections, kidney failure and high altitudes. Some of the symptoms include coughing, problems breathing, paleness and sweating. If untreated, it can lead to cardiac arrest or death.

The Connection between Marathons and Pulmonary Edema

Researchers have debated the connection between marathons and pulmonary edema in the past and often disagreed about the link. However, the study presented at the European Respiratory Society's Annual Congress clearly showed a link between them. The 26 runners included in the research exhibited pulmonary edema on chest radiographs taken after the race. The study found 50 percent had the edema, and women were affected more than men. Additionally, they discovered that there was "no relation between marathon time" and the edema, so runners who were quicker were not more or less likely to be affected.

A Contradiction with Other Research

Recent research has recommended that older marathon runners can safely continue participating in the sport without increased risk. This study from the University of Manitoba in Canada seems to contrast with the findings at the European Respiratory Society's Annual Congress. Pulmonary edema is actually more common in older individuals, yet the Canadian study found that runners over the age of 50 can safely continue with marathons.

The connection between marathons and pulmonary edema must continue to be studied. The limited scope of previous research and small number of participants makes conclusions difficult. It has been an accepted fact that marathons place strain on the hearts of even the most experienced and young runners. However, pulmonary edema has been neglected in many studies.

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Lana has a B.S. degree in Biology and Chemistry. She is an avid athlete, youth coach and follows several sports. Follow @Lana_Bandoim on Twitter.

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