Sickle Cell Drug Lowers Risk of Death
Treatment Also Prevents Pain, Other Complications
April 3, 2003 -- A drug once used to treat cancer may help people with sickle cell anemia live longer and with less pain. A new study shows adults with sickle cell anemia who had frequent episodes of pain and took the drug hydroxyurea had a 40% lower risk of death over a nine-year period.
Sickle cell anemia is an inherited disease that begins in childhood and is named for the sickle-like shape of the red blood cells found in people with the disease. These abnormally shaped cells can cause severe pain in the bones, joints, and abdomen and can block blood vessels.
People with sickle cell anemia commonly suffer from periodic episodes of pain and may also develop a condition called acute chest syndrome, which causes fever and respiratory symptoms such as difficulty breathing.
An earlier clinical trial of hydroxyurea conducted from 1992 to 1995 showed that the drug cut painful episodes and acute chest syndrome in half in people with moderate to severe forms of sickle cell anemia.
In this study, published in the April 2 issue of The Journal of the American Medical Association, researchers followed up those patients from 1996-2001 to see if use of the drug might also reduce the risk of death. During this follow-up period, the 233 patients could start, stop, or continue taking the drug.
Researcher Martin H. Steinberg, MD, of Boston Medical Center, and colleagues found that the patients who took hydroxyurea were 40% less likely to die than the other patients.
They say these findings are particularly promising because the patients assigned to receive the drug in the initial study had frequent painful episodes, a risk factor which is known to increase the risk of death associated with sickle cell anemia. After nine years of follow-up, patients who took the drug and had moderate to severe forms of the disease were the ones who seemed to benefit.
The study also showed that patients who had acute chest syndrome or three or more painful episodes per year during the trial had a significantly higher risk of death than the others. By reducing these complications of sickle cell anemia, hydroxyurea seems to also help these patients live longer by reducing the severity of their disease.
Hydroxyurea was originally developed as a chemotherapy treatment. The study showed very little risk associated with use of the drug during the nine-year study period, but previous studies have linked use of hydroxyurea to an increased risk of leukemia. But researchers say that the risk of complications from sickle cell anemia is at least 10 times greater than the incidence of leukemia in these patients.
In an editorial that accompanies the study, Debra L. Weiner, MD, PhD, of Children's Hospital Boston, and Carlo Brugnara, MD, of Harvard Medical School, say this study shows that expanded use of hydroxyurea is clearly warranted among both children and adults with sickle cell anemia.
"Hydroxyurea provides hope and help for improving quality of life and lifespan for patients with this devastating disease," they write.
SOURCE: The Journal of the American Medical Association, April 2, 2003.