Incidence of Air Travel–Related Pulmonary Embolism at the Madrid-Barajas Airport | Venous Thromboembolism | JAMA Internal Medicine | JAMA Network
[Skip to Navigation]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address Please contact the publisher to request reinstatement.
[Skip to Navigation Landing]
Original Investigation
December 8/22, 2003

Incidence of Air Travel–Related Pulmonary Embolism at the Madrid-Barajas Airport

Author Affiliations

Author affiliations are listed at the end of this article. Dr Yusen is currently or has been a principal investigator and Steering Committee member at Washington University School of Medicine and Barnes-Jewish Hospital in research sponsored by Aventis Inc, Mallinckrodt Medical, Organon Inc, and Sanofi-Synthlelabo Inc; a consultant for Aventis Inc, Organon Inc, and Sanofi-Synthlelabo Inc; and member of the speaker's bureau for Aventis Inc and Dupont/Bristol-Myers Squibb. Dr Jiménez is currently a principal investigator in research sponsored by Aventis Inc and Sanofi-Synthlelabo.

Arch Intern Med. 2003;163(22):2766-2770. doi:10.1001/archinte.163.22.2766

Background  Prolonged air travel and the associated immobilization are risk factors for venous thromboembolism. The occurrence of pulmonary thromboembolism (PTE) under these circumstances is referred to as economy class syndrome. We assessed the incidence of symptomatic PTE in passengers on long-haul flights arriving at Madrid-Barajas Airport, Madrid, Spain, and the association with the number of flight hours.

Methods  We retrospectively reviewed cases of PTE among international travelers arriving at Madrid-Barajas Airport between January 1995 and December 2000. Patients presenting with symptoms of deep venous thrombosis but without symptoms of PTE were excluded. Pulmonary thromboembolism was identified using an algorithm of diagnostic tests. The incidence of PTE and the association with flight duration was assessed.

Results  The average number of passengers per year who arrived at the airport on flights originating abroad in the period analyzed was 6 839 222. Sixteen cases of PTE were detected over the 6-year period. All patients with travel-associated PTE had flight durations of greater than 6 hours. The overall incidence of PTE was 0.39 per 1 million passengers (95% confidence interval [CI], 0.20-0.58). On flights that lasted between 6 and 8 hours, the incidence was 0.25 per 1 million passengers (95% CI, 0-0.75), while on flights longer than 8 hours, the incidence was 1.65 per 1 million passengers (95% CI, 0.81-2.49) (P<.001).

Conclusions  Air travel is a risk factor for PTE, and the incidence of PTE increases with the duration of the air travel. However, the low incidence of PTE among long-distance passengers, similar to that observed in other international airports, does not justify social alarm.