The risk of venous thromboembolism, or VTE, is three times greater for travelers, than for people not cramped on an aircraft or other modes of transportation, according to a new study published online in the July issue of the Annals of Internal Medicine.
The report, warns travelers about the importance of knowing the symptoms of VTE and staying hydrated and mobile while traveling to prevent the condition from developing on long trips.
Symptoms of clotting, also known as deep vein thrombosis include swelling in the arms or legs, skin redness, soreness or pain in the arms and legs or a warm spot on the legs.
The relationship between VTE -- clots that form in the veins, usually the leg, which can be fatal if they move to the lungs or heart -- and travel has long been suggested. But this is the first study to support the theory; previous research has yielded contradictory findings.
Overall, the risk of VTE is relatively small (1 in 20 million), though greater on trips longer than 4 hours, says Jack Hirsh, panel chair of the American College of Chest Physicians.
Researchers found, for each two-hour increase in travel time (by any mode), the risk of VTE, increased by 18 percent, while for air travelers the risk increased to 26 percent.
For the study, researchers looked at 14 reports on VTE and travel that had mixed findings. None of the studies individually showed risk. The relationship was identified by pooling results says, Dariush Mozaffarian, an assistant professor in the Department of Epidemiology at Harvard Medical School.
Hirsh recommends drinking a glass of water every couple hours and flexing your calf muscles against the foot rest if you are unable to get up and move around. Liquids help to dilute the blood, making it less likely to clot. While mobility keeps the blood flowing.
He advises against alcohol and coffee consumption while traveling as they dehydrate you.
Staying mobile and hydrated, are not proven measures to prevent VTE but they help. More research is needed on preventive measures.
People considered high risk for blood clots -- those with chronic illness, estrogen takers, smokers and those who have had clots before - - should talk to their doctor and may need to take a blood thinner before making a long trip. But, even so, the risk is still relatively low.
For those people that must travel on long flights several times a month and are concerned about VTE, there is an option. Studies have shown below-the-knee compression stockings to be helpful.
More than 200,000 new cases of venous thromboembolism occur each year in the U.S. with a 30 percent risk of dying within 30 days, according to the American Heart Association. #