Swimming-induced pulmonary edema in triathletes

Am J Emerg Med. 2010 Oct;28(8):941-6. doi: 10.1016/j.ajem.2009.08.004. Epub 2010 Mar 25.


Background: Pulmonary edema related to water immersion has been reported in military trainees and scuba and breath-hold divers, but rarely in the community. To date, no risk factors for this phenomenon have been identified by epidemiological methods. Recently, sporadic reports of swimming-induced pulmonary edema (SIPE) have emerged in the triathlon community. We surveyed the population of a national North American triathlon organization (USA Triathlon) to determine prevalence of and risk factors for symptoms compatible with SIPE.

Methods: We surveyed the population of USA Triathlon through the organization's monthly newsletter distribution channel. We evaluated prevalence of symptoms compatible with pulmonary edema, and then followed up with a case-control study that included additional cases we had identified previously, to identify risk factors for this condition among triathletes.

Results: Symptom history compatible with SIPE was identified in 1.4% of the population. Associated factors identified in multivariable analysis included history of hypertension, course length of half-Ironman distance or greater, female gender and use of fish oil supplements. Of the 31 cases reported, only 4 occurred in the absence of any associated factors.

Conclusions: The identification of hypertension and fish oil in particular as risk factors raise questions about the role of cardiac diastolic function in the setting of water-immersion cardiac preload, as well as the hematologic effects of fish oil. Mechanistic studies of these risk factors in a directly observed prospective cohort are indicated.

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Athletes*
  • Chi-Square Distribution
  • Female
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Odds Ratio
  • Pulmonary Edema / epidemiology
  • Pulmonary Edema / etiology*
  • Risk Factors
  • Sex Factors
  • Surveys and Questionnaires
  • Swimming*
  • Young Adult