Deep vein thrombosis linked to most travel

From staff and wire reports

GENEVA, Switzerland -- International medical experts and officials from 16 major airlines across the globe on Tuesday heard a leading expert on deep vein thrombosis link the condition to most types of travel. Organized by the World Health Organization's cardiovascular disease unit, the closed-door meetings in Geneva, Switzerland, began Monday and concluded Tuesday.

"Travel-related thrombosis is a better name," Dr. John Scurr, a British surgeon who has studied the syndrome, told Reuters. "Studies have shown it is a common travel problem." Scurr is a surgeon at Middlesex and University College Hospital in London, England.

PREVENTION Snacking, moving can decrease risk of flight-related blood clots

Also speaking Tuesday was Dr. Derek Yach of the WHO, who agreed with Scurr that deep vein thrombosis is probably a bigger issue than it currently appears to be. Physicians say the condition is still rare, however.

Gregory Hartl, a spokesman for the United Nations health agency, called the two-day meeting significant. "We've come to this with an open mind. We need to review the research done and see what gaps need filling and what, how and when it needs to be done on an international scale," he told The Associated Press.

Deep vein thrombosis, also called traveler's thrombosis and DVT, has been linked to the low mobility fostered by long-haul flights and other forms of protracted travel in cramped spaces, such as automobile, bus and train trips. It was inaccurately nicknamed "economy class syndrome" because it was believed that the cramped conditions in coach class contributed to it.

In fact, DVT has taken place in passengers riding in business and first class -- and even in people who sit for long periods at their office desks.

"It's the first time that airlines of the world have gotten together under the auspices of the WHO to talk about a problem that has been booming in the past year or so," Jarnail Singh, chairman of Singapore Airlines' civil aviation medical board, told Reuters Monday.

DVT is caused by blood clots that can form when blood pools -- most often in the legs -- during long periods of inactivity. The clots could break off and travel to the lungs, brain or heart, possibly causing heart attack and stroke.

Experts still are unsure how long people must remain still to be in danger, although known risk factors include age, obesity, smoking, pregnancy, cancer, recent surgery, hormone therapy or a history of DVT.

The condition has been blamed for at least 30 deaths in three years at just one hospital in London, England. A study of cases at Ashford Hospital, just minutes from the city's Heathrow Airport, revealed that though deaths are relatively rare, the condition is causing growing concern.

"It's the red-eye flights from the west of the United States and the Far East, and also from Australia," Dr. John Belstead told CNN. "It's mostly people who sleep in their seats."

Vascular surgeon Scurr has studied 200 people flying long distances before and after their trip and is due to publish his findings soon in The Lancet, a medical journal.

In October, 28-year-old Briton Emma Christofferson died after collapsing at Heathrow at the conclusion of a 12,000-mile flight from Sydney, Australia. Shortly thereafter, British Airways became one of the first airlines to warn its passengers about the potential dangers of DVT. Others have also begun showing videos and giving tips on how to avoid the condition during long flights. Australian airlines Qantas and Ansett plan to begin printing cigarette-pack-style warnings on tickets.

Eating a light meal and drinking nonalcoholic beverages may decrease the risk of DVT, according to Japanese researchers, who found that consuming snacks and fluids increased oxygen levels in the body and brain.

Increased blood volume helps to keep circulation going, lessening the chance that blood can pool in the legs.

Physicians also have recommended that travelers get up and walk periodically during long trips. If this is difficult, legs and ankles should be flexed and weight should be shifted in the seat. Alcohol and caffeine intake should be limited, doctors said.

Airlines have been reluctant to endorse the idea of travelers getting up and walking during flights because of the danger of more severe injuries in the event of turbulence.

The European Commission said last month that it was funding the largest-ever study into the effects of flying on passenger health.

Included in this week's talks, which were jointly sponsored by the Montreal, Quebec-based International Civil Aviation Association, are representatives from the International Air Transport Association, the International Civil Aviation Association, Air France, Alitalia, British Airways, Cathay Pacific Airways, Emirates, Iberia, Japan Airlines, KLM, Lufthansa, Qantas, Singapore Airlines, South African Airways, Swissair, United Airlines, Varig and Virgin Atlanta Airways.

CNN Medical Correspondent Rhonda Rowland, CNNfn Correspondent Tom Bogdanowicz, Reuters and The Associated Press contributed to this report.

Doctors, airlines warn of blood clot risk
January 11, 2001
Airlines urged to issue health warnings
November 22, 2000
Woman dies from blood clot after long-haul flight
October 23, 2000

World Health Organization
International Air Transport Association
The Lancet Home Page
International Civil Aviation Organization
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Centers for Disease Control and Prevention: Traveler's Health

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