Transfusions increase hospital clot risk

ROCHESTER, N.Y., Nov. 25 (UPI) -- Blood transfusions used to treat anemia in patients with cancer are associated with an increased risk of life-threatening blood clots, U.S. researchers say.

Scientists at the University of Rochester Medical Center in New York say the findings pose a quandary for doctors who want to prevent thromboembolism -- a blood clot that breaks loose and is carried by the blood stream causing a stroke or pulmonary embolism -- one of the leading causes of illness and death in people with cancer.

Lead author Dr. Alok Khorana says that when patients receive chemotherapy, doctors watch closely for signs of anemia, a common side-effect that causes fatigue, dizziness and headaches. To combat the anemia, oncologists prescribe medications known as erythropoiesis-stimulating agents, which boost red-blood-cell production.

The researchers analyzed discharge summaries in the University Health System Consortium, which includes information on more than 500,000 people hospitalized at 60 medical centers from 1995-2003.

Khorana and his team studied data on more than 70,500 patients who received a blood transfusion. Among those patients, 7.2 percent developed venous thromboembolism and 5.2 percent developed arterial thromboembolism -- significantly higher than the 3.8 percent and 3.1 percent rates, respectively, for patients in the study who didn't receive transfusions. However, the figures are comparable to the data on erythropoiesis-stimulating agents, the researchers said.

The findings are published in the Archives of Internal Medicine.