Discovering Hope

‘Silent strokes’ in children

Children who have sickle cell disease along with high blood pressure and anemia are at increased risk for silent strokes, Vanderbilt researchers found.

Internationally renowned sickle cell expert Michael DeBaun, M.D., vice chair for Clinical Research in Vanderbilt’s Department of Pediatrics, led the multi-center study to examine the interplay between high blood pressure, anemia and stroke in children with sickle cell disease.

The research is part of the ongoing Silent Cerebral Infarct Transfusion (SIT) Trial, the largest study to date on children with sickle cell disease funded by an $18 million National Institutes of Health grant.

Nearly 100,000 people in the United States are living with sickle cell disease, a group of inherited blood disorders.

Silent strokes in children are rare, but a more common neurologic condition in children with sickle cell. The permanent brain injury can affect children’s ability to think and perform tasks and their academic performance.

Looking at MRI results from 814 children, ages 5 to 15, researchers found one-third (31 percent) suffered silent stroke. Anemia (low hemoglobin) or high blood pressure alone increased children’s risk for stroke. Children with both risk factors had a fourfold increased chance for silent stroke.

DeBaun, J.C. Peterson, M.D., Chair in Pediatric Pulmonology, said the results could help lead to the identification of new therapies to prevent silent stroke in children with sickle cell disease.

– by Christina Echegaray

No heart risk with ADHD drugs

Medications used to treat attention deficit hyperactivity disorder (ADHD), the most common neurobehavioral disorder in children, do not increase risks for heart disease or heart attack in children and young adults, a Vanderbilt study found.

William Cooper, M.D., MPH, professor of Pediatrics and Preventive Medicine, authored the study, which looked at 1.2 million patients using Ritalin, Adderall, Concerta and Strattera, between 1998 and 2005, to examine potential risks posed by the drugs.

A 2006 Food and Drug Administration advisory warned of a potential link between the medications and heart risk. Then, in 2008, the American Heart Association reviewed existing research and concluded it was reasonable for physicians to seek an electrocardiogram (EKG) before prescribing ADHD medications.

Cooper and other Vanderbilt researchers looked over medical records from four different health plans, checking for any incidence of serious cardiovascular events. They found no significant increase in risk for patients who used ADHD medications and those who did not.

– by Carole Bartoo

Cooling blankets and infant brains

Pediatric neurologists and neonatologists in Vanderbilt’s Neonatal Intensive Care Unit (NICU) are conducting research that may better define what happens in the brains of newborns who have suffered from oxygen deprivation, and what brain cooling therapy can achieve.

Use of a “cooling cap” within six hours is now the standard of care when an otherwise healthy, full-term infant experiences a serious lack of oxygen, called anoxic brain injury. The therapy uses cool water to bring the temperature of the brain down about five degrees and helps reduce serious long-term brain damage and death by about one-third.

Now a switch has been made to a cooling blanket instead of a cap. The blanket is as effective in its brain-protecting capacity, but it offers researchers an opportunity to better assess what is happening in the brain as it is cooled. They will examine what happens in the first 72 hours after anoxic injury, a critical window in which the cooling seems to have its maximum brain-preserving effect.

– by Carole Bartoo