UVM Participates In National Blood Related Study

Deep vein thrombosis, a potentially fatal condition that afflicts about 270,000 people annually in the United States, will likely be treated differently due to the dramatically positive results of a new study, which is featured in the Feb. 24 electronic version of the New England Journal of Medicine.

Researchers have found that long-term use of a low dosage of the drug warfarin, a commonly available blood thinner also known by the brand name Coumadin, provides an effective and safe treatment for this problem.

The University of Vermont (UVM) was one of 52 international sites that participated in the Prevention of Recurrent Venous Thrombosis (PREVENT) study, a randomized, double blind, placebo-controlled study involving a total of 508 participants worldwide. Co-author of the study report and Associate Professor of Medicine Mary Cushman, M.D., led the study at the UVM/Fletcher Allen Health Care site, which had one of the highest patient enrollment rates with 27 local-area participants.

Also known as phlebitis, deep-vein thrombosis is a blood clot that forms in the deep veins of the thigh or calf, resulting in pain and discomfort. The greater concern, however, is the 20 percent risk that a piece of one of these clots may break off, travel through the veins and block blood flow to the lungs, causing breathing problems or even death.

The condition attracted public attention recently following the sudden deaths of long-haul airline travelers who were believed to have developed leg clots that became fatal.

Previous to this study’s findings, patients who suffered a venous thrombosis episode – called a venous thromboembolism – were treated with a standard anticoagulation therapy: a combination of several days of an intravenous or injected blood thinner followed by 3 to 12 months of full-dose warfarin.

Once the treatment was stopped, however, the blood clots would recur at a rate of 6 to 9 percent per year.

The goal of the PREVENT study was to determine whether long-term use of a lower dosage of warfarin would safely and effectively prevent recurrent venous thrombosis in patients who had completed the standard anticoagulation therapy.

“This is good news for the thousands of people who suffer from deep vein thrombosis,” said Cushman.

“Our small center at the University of Vermont/Fletcher Allen enrolled the third highest total of participants out of all 52 sites involved in the study, and we are proud that our academic medical center was able to play a key role in research that will have an impact on how we care for our patients.”

Approximately 1200 people in Vermont suffer from deep vein thrombosis annually.

The condition most commonly occurs in individuals aged 60 years or older.

Among those at risk for developing this condition are those with obesity, diabetes, or cancer; people with inherited blood conditions; pregnant women or women who take oral contraceptives or hormone replacement therapy; and individuals who have had surgery or suffered a bone fracture.