Special stockings commonly given to stroke patients to prevent
blood clots don't work, but they cause ulcers and blisters, a new study reported Wednesday.
Doctors often prescribe the tight, thigh-high stockings to
patients who have suffered a stroke, seeking to prevent blood clots
in patients' legs - which could prove fatal if they break off and
reach the heart or lungs.
About two-thirds of stroke patients can't walk when admitted to
hospital, and up to 20 percent of those patients develop a blood
clot in their legs. The stockings squash the legs and force the
blood to circulate better, and can be used in place of, or
alongside, anti-clotting drugs like heparin.
No anti-clot action
But in a study of more than 2,500 stroke patients in Australia,
Britain and Italy, doctors found the stockings did nothing to
reduce the chances of a clot. Not only that, but they caused
problems like skin ulcers and blisters.
The results were simultaneously published in the Lancet medical
journal and presented at the European Stroke Conference in
Stockholm on Wednesday.
Some experts were surprised by the findings. "We have used these stockings because we assume they work," said Dr. Ralph Sacco, president-elect of the American Heart Association,
who was not linked to the study. "But sometimes you're surprised
when you find out the truth with a randomised trial."
Effective in surgery patients
The stockings have been proven to reduce clots in surgery
patients, so experts had long thought the low-cost solution might
also help stroke patients.
Stockings make no difference
In the study, about half of the patients received standard care in addition to the stockings. The other half just received the standard care. Experts took an ultrasound of patients' legs after about 7 to 10
days, and then again after 25 to 30 days. About 10 percent of
patients in both groups developed blood clots.
In the group wearing stockings, 5 percent reported side effects
such as skin problems and blisters. That compares to 1 percent in the
group not given the stockings.
The study was paid for by Britain's Medical Research Council,
the Scottish government, the health charity Heart and Stroke
Scotland, Tyco Healthcare in the United States and the U.K. Stroke
In Britain, draft guidelines recommend patients wear the
stockings and they are used to treat an estimated 80,000 patients
per year. Martin Dennis, of the University of Edinburgh and one of
the study authors, said he has contacted British officials to
suggest they reconsider their advice.
UK stroke units use stockings
"This should cause a big change in how patients are treated,"
Dennis said, noting that in 2002, 90 percent of stroke units in
Britain used the stockings. In the United States, stockings for stroke patients are far less
popular than in the UK.
Dr. Marc Mayberg, co-director of the Seattle Neuroscience
Institute, said he hadn't recommended the stockings for patients in
about 20 years. He said the stockings were cumbersome and difficult
for many patients, whose legs were paralysed, to put on and take
Recommendations from the American Heart Association published in
2005 advised doctors to consider using the stockings in addition to
an anti-clotting drug, or for patients who can't take such drugs.
Sacco said American doctors were more likely to use drugs
instead of stockings to prevent clots. He thought the guidelines
promoting stockings might now have to be revised.
"With this lack of effect, doctors may be much less inclined to
use them," he said. - (Maria Cheng, Sapa, May 2009)
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