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What is Your Risk of Getting DVTs While Flying?

The WRIGHT project and the World Health Organization found that a passenger on a long haul flight has roughly a 1 in 4,500 chance of developing this sort of blood clot.

WRIGHT project manager, Frits Rosendaal, M.D., Ph.D. of Leiden University says his study suggests that three types of factors can boost your risk of developing a blood clot — how often you take long flights, your particular physiology, and what you do on the plane.

Frequent Flyers

— Frequency: Frequent fliers are at higher risk of developing clots. Taking five flights within a three month period increases you chances of forming a blood clot by a factor of three, when compared to only taking one or two flights in three months.

— Duration: Longer flights increase risk. Flights over 12 hours are 70 times more likely to produce a blood clot than flights lasting less than four hours.

Your Body

— Weight: Obesity seems to be a risk factor. Having a body mass index (BMI) over 30 doubles your chance of developing thrombosis.

— Height: People who are extremely tall or short also have higher risk. Anyone over 6'3" or under 5'3" is six times more likely to form blood clots on a long flight.

— Blood abnormalities: Certain clotting disorders, such as Factor V Leiden, increase risk by a factor of five.

Sleeping Onboard

— Alcohol: Drinking so much alcohol that you fall into a deep sleep and don't budge for hours at a time doubles your chances of developing a blood clot.

— Sleeping pills: Taking sleeping pills also doubles your risk.

- Shannon Fowler, Ph.D.

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