Wednesday, February 6, 2008

Blood clot treatment puts patients at greater risk of decreased level of platelets
by Kelly Winget

Hospitalized patients are at higher risk for developing blood clots, often either as a complication of surgery or from lying in bed for extended periods. As a result, many doctors treat their patients with heparin while in the hospital to help prevent blood clots from forming.

However, DCRI researchers have recently learned that these patients often develop thrombocytopenia, or a reduced level of platelets in the blood. Thrombocytopenia can cause excess bleeding, nosebleeds and bleeding gums. Researchers found that developing this condition indicates a higher risk of death or life-threatening events.

Results of the study, led by the DCRI's Gustavo Oliveira , MD, were published in the January 14 issue of the Archives of Internal Medicine .

For the study, CATCH, researchers analyzed data on 2,420 consecutive hospitalized patients who were treated with heparin for four or more days. They were looking to find out how common thrombocytopenia was, what the predictors for developing the condition were and how physicians managed thrombocytopenia.

Of the patients, 36 percent developed thrombocytopenia. Those patients had significantly higher risk of death, heart attack or heart failure. A reduction in platelet levels by more than 70 percent was the biggest predictor of death, followed by a reduction in platelet levels by 50 to 70 percent. Older patients and those who received longer heparin treatments also had greater risk of death.

Despite the increased likelihood of developing thrombocytopenia while being treated with heparin, Oliveira notes that it is an under-recognized and under-treated complication.

Guidelines for patients who are considered at high risk for developing heparin-induced thrombocytopenia (HIT) include monitoring platelet levels, using non-heparin anti-blood clotting drugs and avoiding vitamin K.

But researchers found that less than 10 percent of the patients who developed HIT were suspected of having it. When physicians did suspect HIT, there were considerable delays in stopping the heparin, consulting with hematology specialists or starting the patient on a different anti-blood clot treatment.

“Collectively, our observations identify a serious gap between published guidelines and clinical practice in the United States ,” Oliveira and the research team note. “The currently practiced diagnostic approach and management of patients with thrombocytopenia at risk for HIT, as documented in the CATCH study, raises serious concerns and should prompt action to narrow the gap between guidelines and clinical practice in the United States .”

Other DCRI researchers include Drs. Richard Becker; Kevin Anstrom; Peter Berger; Eric Eisenstein; Victor Tapson; Magnus Ohman, and Christopher Granger; and Emily Honeycutt and Linda Davidson-Ray.