Childhood stroke deaths drop, but still higher among blacks
SAN ANTONIOStroke deaths for children have declined sharply, but black children have higher stroke death rates than other youngsters, according to research presented at the American Stroke Associations 27th annual meeting. The American Stroke Association is a division of the American Heart Association.
Recent declines in adult stroke deaths have been attributed to more people controlling well-known risk factors such as hypertension and cigarette smoking. But these factors are irrelevant in children.
Childhood stroke deaths are poorly understood, says Heather Fullerton, M.D., the studys lead author. You cant turn to the risk factors important for strokes in adults, such as hypertension, a poor diet or diabetes, and apply them to kids.
Although childhood strokes are far less common than adult strokes, they, too, can kill or leave survivors disabled. Only a few small studies have examined childhood stroke deaths, according to Fullerton, a child neurology fellow at the University of California San Francisco. Known risk factors for childhood hemorrhagic strokes (caused by bleeding) include brain tumors or vascular malformations, hemophilia, cancer and sickle cell disease. Childhood ischemic strokes (caused by blockages) have also been linked to sickle cell disease and cancer. Risk factors that contribute to ischemic strokes alone include meningitis, encephalitis, congenital heart disease and certain blood clotting disorders.
In this study, researchers analyzed data from the National Center for Health Statistics mortality database, which compiles death certificate data across the country. They examined childhood stroke deaths in people age 20 and under who died from a stroke, as specified on death certificates, between 1979-98. They found an average of 244 deaths per year due to childhood stroke in the United States.
Overall, the study found stroke deaths declined by 58 percent in the 20-year period. However, the reduction in deaths varied by type of stroke. Hemorrhagic strokes showed the steepest fall: childhood stroke deaths from subarachnoid hemorrhagic strokes (bleeding into the space between the brain and the skull) dropped by 79 percent, while strokes from intracerebral hemorrhages (bursting of a defective brain vessel) declined by 54 percent.
The declines were not as marked for deaths from ischemic stroke, which results from a blood clot that blocks blood flow to the brain. Ischemic stroke deaths declined 19 percent in the same time period.
These declines were tempered by the finding that black children and boys had higher risks for dying of strokes, says Fullerton. Black children were more than twice as likely to die from strokes caused by intracerebral hemorrhage, and approximately 75 percent more likely to die from both ischemic strokes and subarachnoid hemorrhage. Black adults are also at greater risk from stroke than other adults.
No factors, such as sickle cell diseasewhich is more prevalent in blacks than whites–fully accounted for excess stroke deaths, Fullerton notes.
Boys were 30 percent more likely to die from subarachnoid hemorrhage and 21 percent more likely to die from intracerebral hemorrhage than girls. Stroke is also more common in adult men than women.
With further research, we may be able to uncover other risk factors that we are not recognizing and find effective ways of preventing strokes in these kids, Fullerton says.
She suspects an unknown genetic predisposition may play a role in these deaths. As for the higher stroke rates in boys, Fullerton suspects that hormonal differences may be a factor.
The study found no stroke belt for children as there is in adults, where deaths are disproportionately higher in the southeastern United States.
Next, the research team plans to examine a California-wide database, exploring the impact of socioeconomic status, insurance coverage or lack thereof, and geographic factors, such as urban and rural residence on childhood stroke deaths.
Coauthors are Dane M. Chetkovich, M.D.; Yvonne Wu, M.D.; Wade S. Smith, M.D.; and S. Claiborne Johnston, M.D.