WEDNESDAY, Feb. 1, 2012 (HealthDay News) -- Many children who suffer a stroke had some sort of an infection in the days leading up to the stroke, a new study says.
However, childhood stroke is rare and parents shouldn't be unduly alarmed by these findings, the researchers noted.
The researchers analyzed data collected from 2.5 million children enrolled in a health plan in California between 1993 and 2007 and identified 126 cases of childhood ischemic stroke, which is caused by reduced blood flow to the brain. These cases were compared with a control group of 378 children of similar age who didn't suffer a stroke.
The study found that 29 percent of the children who suffered a stroke had an infection in the two days before the stroke, compared with 1 percent of the control group children.
Thirteen percent of the children who suffered a stroke had an infection three to seven days before their stroke, compared with 2 percent of the control group children.
The increased risk of stroke did not continue after the first month of infection, according to the study slated for Wednesday presentation at the American Stroke Association meeting in New Orleans.
The children in the stroke group ranged from infants to adolescents. The average age was 10.5 years and the oldest child was 19. The researchers found no difference in stroke between girls and boys or among ethnic groups.
The researchers did find that acute infections were more likely to trigger stroke than chronic infections.
"These were predominantly minor acute infections and represented a variety of infections, including upper respiratory infections, urinary tract infections and ear infections. No particular type of infection predominated," principal investigator Dr. Heather Fullerton, director of the Pediatric Stroke and Cerebrovascular Disease Center at the University of California, San Francisco, said in a stroke association news release.
In the United States, the incidence of stroke in children is about five per 100,000 per year, the release noted.
"Childhood infections are exceedingly common, while childhood strokes are uncommon," Fullerton said. "Parents should not be alarmed at the findings of this study. We suspect that there are rare genetic factors that may place some children at risk for this uncommon effect of common infections."
Infection is a known risk factor for ischemic stroke in adults.
Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
The Nemours Foundation has more about childhood stroke.