Researchers at the Centers for Disease Control and Prevention, Atlanta, GA determined rates of acute stroke hospitalization and the prevalence of stroke risk factors among children and young adults hospitalized for acute stroke, 1995-2008. Seven consecutive 2-year time intervals were selected, and data for three age groups were compared: 5 to 14 years, 15 to 34 years, and 35 to 44 years. The prevalence of hospitalizations of acute ischemic stroke increased among all age and gender groups, except females aged 5 to 14 years; 31.3% increase from 3.2 to 4.2/10,000 (p=0.005). The largest increases in ischemic stroke occurred in males of all age groups. Overall, males had higher rates of subarachnoid hemorrhage, intracerebral hemorrhage, and ischemic stroke hospitalizations than females among those aged 15 to 34 and 35 to 44 years (p<0.001). Females aged 15 to 34 years and males and females aged 35 to 44 years showed a decrease in hospitalizations for subarachnoid hemorrhage, whereas females aged 5 to 14 years showed an increase for subarachnoid hemorrhage. The rate of ischemic stroke with sickle cell disease (SCD) in children aged 5 to 14 years decreased by more than half from years 1995-1996 to 2007-2008 (from 27.8 to 12.6%, p<0.001), whereas the rate of alcohol abuse in this age group increased significantly from 2.5% in 1995-1996 to 6.2% in 2007-2008 (p<0.001).
Coexisting conditions with stroke included hypertension, diabetes, obesity, lipid disorders, congenital heart disease, migraine, coagulation defects, tobacco use, and patent foramen ovale. The prevalence of these risk factors among adolescents and young adults (aged 15-44 years) hospitalized with acute ischemic stroke increased significantly (p<0.01) from 1995 to 2008. 
COMMENT. The American Heart Association, in a most definitive statement and review of stroke in infants and children , finds 55% of strokes in children are ischemic and the remainder is hemorrhagic, whereas among adults, 85% are ischemic. About one-half of children presenting with an acute focal neurological deficit due to stroke have a previously identified risk factor, and the remainder has >1 additional risk factor . The most common underlying conditions are SCD and congenital or acquired heart disease. Head trauma, often minor and sports related, is a trigger for arterial stroke  and dehydration for venous stroke . Infections, including varicella, meningitis, tonsillitis, and otitis media are risk factors for both. Pediatric endocarditis was a risk factor for stroke in 7 patients reported from Children's Memorial Hospital, Chicago, 3 patients having mycotic aneurysms. 
The peak age for ischemic stroke and intracerebral hemorrhage in children is in the first year of life, and one third of childhood stroke cases present in this age group. Subarachnoid hemorrhage is more common among teenagers . An excess of strokes in boys and in those of African American ethnicity is independent of SCD.