Compression stockings for preventing deep vein thrombosis in airline passengers

Venous thrombosis associated with air travel was reported in the early 1950s and was referred to as" economy class syndrome", although it is now recognized that reduced movement on long-haul flights is more important than sitting class. There is no evidence that thrombosis is more likely in economy class than in business class or first class passengers.

flights of 8 hours or more are associated with a 2-4-fold increased risk of deep venous thrombosis compared to those who do not travel, but the average absolute risk is low (approximately one symptomatic event per 2 million arrivals, with a mortality rate of approximately 2 %)

Most travelers who develop venous thrombosis or pulmonary embolism also have one or more predisposing risk factors: old age, obesity, recent trauma or surgery, a history of thrombosis, venous insufficiency, malignancy, hormone therapy, or pregnancy.

Limited evidence suggests that Leyden factor V and a mutation of the prothrombin gene predispose to thrombosis in otherwise healthy travelers.

are compression stockings (or "air travel socks")really necessary
reduce the risk of deep vein thrombosis in airline passengers?

Stockings are worn throughout the flight and they exert light pressure on the ankle joint and Shin muscles.
Pressure combined with leg movement helps the blood in the superficial blood vessels move to the deep veins and return to the heart.

A large study in 2016: the review included 11 trials (2906 participants).
Almost half of the participants were randomly assigned to wear stockings during the flight, lasting at least five hours, while participants from the other half did not wear stockings.

None of the passengers developed DVT with symptoms (pain, swelling), serious complications (pulmonary embolism), or death was reported.
Passengers were carefully examined after the flight to detect any problems related to blood circulation in the legs, even if they themselves did not notice any problems.

Wearing compression stockings led to a significant reduction in asymptomatic DVT among air passengers who were identified as wearing compression stockings, compared to those who did not wear them.

Passengers who wore compression stockings had less superficial vein thrombosis than those who did not wear them.

Byard RW. Deep venous thrombosis, pulmonary embolism and long-distance flights. Forensic Sci Med Pathol. 2019;15(1):122-124. doi:10.1007/s12024-018-9991-9

Gallus AS. Travel, venous thromboembolism, and thrombophilia. Semin Thromb Hemost. 2005;31(1):90-96. doi:10.1055/s-2005-863810