"This review shows that airline passengers travelling for long distances can expect a substantial reduction in the incidence of symptomless DVT if they wear compression stockings," says lead Review Author Prof Mike Clarke, Director of the UK Cochrane Centre, Oxford.
DVTs are blood clots that partially or totally block veins running deep inside the body, usually in the legs. They have been of concern for years in patients lying in hospital beds, and more recently in passengers on aircraft. These people share a number of common features: both sets tend to become dehydrated and breathe air that has a low humidity, and both groups do not move about very much.
To counteract this lack of movement, patients in hospitals are often encouraged to wear stockings that apply pressure to the lower leg. The gentle pressure helps maintain blood flow and reduces the number of blockages. As people have become more aware of the risks of developing a DVT while flying, researchers have started to assess the potential benefit of compression stockings in airline passengers.
Performing a systematic review, the Review Authors based in Oxford and Copenhagen searched for high quality studies in which people had been randomly assigned to either wear or not wear stockings, before flights that would last at least seven hours. "We found nine such trials involving over 2,800 people of different ages, sexes and risk categories, who were split almost equally between the groups" said Monica Kjeldstr°m from the Nordic Cochrane Centre in Denmark.
Of the 2,637 people with follow-up data, a total of 47 people who were not wearing stockings developed DVTs, compared with only 3 of the stocking-wearing group. Review Author Dr Sally Hopewell, another of the researchers, said "the DVTs in these studies were detected by a clinical examination after the flight and none of the DVTs caused symptoms that the person was aware of or led to other health problems."
Notes for editors:
1. Review Paper: Clarke M et. al: Compression stockings for preventing deep vein throm-bosis in airline passengers. The Cochrane Database of Systematic Reviews 2006, Issue 2. Art. No.: CD004002.pub2. DOI: 10.1002/14651858.CD004002.pub2.
2. The Cochrane Library contains high quality health care information, including Systematic Reviews from The Cochrane Collaboration. These Reviews bring together research on the effects of health care and are considered the gold standard for determining the relative effectiveness of different interventions. The Cochrane Collaboration (http://www.cochrane.org) is a UK registered international charity and the world's leading producer of systematic Reviews. It has been demonstrated that Cochrane Systematic Reviews are of comparable or better quality and are updated more often than the Reviews published in print journals¬.
3. The Cochrane Library can be accessed at http://www.thecochranelibrary.com. Guest users may access abstracts for all Reviews in the database, and members of the media may request full access to the contents of the Library. For further information, see contact details below.
4. A number of countries have national provisions by which some or all of their residents are able to access The Cochrane Library for free. These include:
5. There are also several programmes, such as the Health InterNetwork Access to Research Initiative (HINARI) that provide access in developing countries. To find out whether your country is included in any of these programmes/provisions, or to learn how to get access if you don't already have it, please visit: http://www.thecochranelibrary.com.
If you would like to see a full list of Reviews published in the new issue of The Cochrane Library, or would like to request full access to the contents of The Library, please contact.
Contact: Polly Young
Tel: +44 (0)1243 770633
¬ Jadad AR, Cook DJ, Jones A, Klassen TP, Tugwell P, Moher M, et al. Methodology and reports of systematic Reviews and meta-analysies: a comparison of Cochrane Reviews with articles published in paper-based journal.
About John Wiley & Sons, Inc.
Founded in 1807, John Wiley & Sons, Inc., provides must-have content and services to customers worldwide. Our core businesses include scientific, technical, and medical journals, encyclopedias, books, and online products and services; professional and consumer books and subscription services; and educational materials for undergraduate and graduate students and lifelong learners. Wiley has publishing, marketing, and distribution centers in the United States, Canada, Europe, Asia, and Australia. The company is listed on the New York Stock Exchange under the symbols JWa and JWb. Wiley's Internet site can be accessed at http://www.wiley.com.
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.