Zahuranec DB et al. (2005) Is it time for a large, collaborative study of pediatric stroke? Stroke 36: 1825–1829

Little is known about the risk factors for childhood stroke. Indeed, the US National Institute of Neurological Disorders and Stroke has highlighted the need for more work in this area. A recent, community-based analysis by Zahuranec and colleagues suggests that large, multicenter studies—or even a national surveillance system—are needed if useful information is to be generated.

As part of the Brain Attack Surveillance in Corpus Christi (BASIC) project in Texas, the investigators recorded the incidence of pediatric stroke during 2002 and 2003. The study population of approximately 92,000 included individuals aged >1 month and <20 years, and comprised equal numbers of Mexican Americans and non-Hispanic whites.

According to discharge diagnosis codes, there were 15 acute cerebrovascular events during the study period. Following examination of the medical records, eight of these cases were validated as ischemic stroke, transient ischemic attack, subarachnoid hemorrhage, or intracerebral hemorrhage. The corresponding annual incidence rate of childhood stroke was calculated as 4.3 per 100,000 (95% CI 1.9–8.5). On the basis of this information and assuming a risk ratio of 1.3, the authors estimated that a sample study population of >3 million would be needed for a 4-year, case-control study of risk factors such as gender. Less-common risk factors, such as factor V Leiden heterozygosity, would call for much larger study populations, as would the analysis of stroke by subtype.

In conclusion, an improved understanding of the risk factors for childhood stroke will require long-term, large-scale studies; the authors invite further debate on whether such investment is warranted.