Blood Transfusions can cut Stroke Risk for Kids with Sickle Cell Anemia
Children with sickle cell anemia can benefit from monthly blood transfusions, researchers in charge of a new clinical trial reported. According to the study, the transfusions can reduce the children's risk of recurrent "silent" strokes, which have been tied to negatively impacting the children's intelligence quotient (IQ).
Sickle cell anemia is a genetic disorder that is characterized by abnormally shaped red blood cells. The cells, which are "sickle-shaped," can block blood flow, causing pain, organ damage and an increased risk of infection. Roughly one in three children with this disease will suffer from a silent stroke. In this multi-institutional study that started at Washington University School of Medicine in St. Louis, MO, researchers set out to find a way to reduce children's risk of recurrent silent stroke.
The researchers first screened sickle cell anemia patients for evidence of a silent stroke and identified 196 children between the ages of five and 15. 99 of them then received monthly blood transfusions that lasted three years whereas the remaining 97 children acted as the control group and did not get any transfusions at all. Over the time span, six children from the treatment group experienced another silent stroke and14 children from the control group did as well.
"We think the transfusions are helping because they raise the total amount of circulating blood and lower the percentage of sickle-shaped cells in the patient's bloodstream," said coauthor Allison King, MD, assistant professor of pediatrics and of occupational therapy according to the university's news release. "Keeping the sickled cells to less than 30 percent of total blood cells seems to be ideal."
The team added that the blood transfusions also reduced the children's risk of sickle cell crisis, which causes acute pain at irregular moments. Overall, the transfusions were considered successful. The researchers believe that all children with sickle cell anemia should be screened for silent stroke at least once before entering elementary school. If they have already suffered from one, receiving monthly blood transfusions can greatly reduce their risk of experiencing another one.
"The data make transfusion the only evidence-based option to prevent stroke recurrence and further brain injury in this vulnerable population," said coauthor Michael Noetzel, MD, professor of neurology and of pediatrics and chair of the study's neurology committee. "Now that we have identified a viable treatment option, early detection of silent cerebral strokes should become a major focus for clinicians and families of children with sickle cell disease."
Blood transfusions do come with risks, which include infection, allergic reactions and long-term accumulation of iron, which could threaten heart and liver health. The researchers added that risk of infection is low. The team plans on carrying out longer studies in order to determine whether or not monthly blood transfusions remain beneficial.
The study, "Controlled Trial of Transfusions for Silent Cerebral Infarcts in Sickle Cell Anemia," was published in the New England Journal of Medicine.