Host factors and childhood injury: the influence of hyperactivity and aggression.

OBJECTIVE: This study examined the association between hyperactivity, aggression, and unintentional childhood injury among a cohort of children aged 5-12 years. Participants were recruited utilizing a two-tier randomization process from primary schools in Brisbane, the capital city of Queensland, Australia. Information on hyperactivity and aggression was collected by trained interviewers using a semi structured questionnaire and episodes of injury were reported by parents using an injury event report form. Eight hundred and seventy-one children were recruited into the study of which 811 (93%) completed the full 12 months of follow-up. All subsequent analysis was limited to the children who were retained for the full study period.
METHODS: One hundred and twenty-one children were categorized as hyperactive and 48 as aggressive. Boys were nearly twice as likely as girls to be categorized as hyperactive or aggressive, although this difference was not statistically significant for aggression. Lower socioeconomic status (SES) as measured by household income was also associated with aggression while more children from middle SES households as measured by both household income and maternal education were hyperactive compared with children from either low or high SES households.
RESULTS: After adjusting for key confounding factors, children with high hyperactivity scores had an increased risk of all injuries (OR 1.98, 95% CI 1.48-2.64) and medically treated injuries (OR 1.56, 95% CI 1.01-2.43). Male gender was also a significant predictor of injury. Initiatives to prevent childhood injuries should take into account that child temperament may act as a mediating factor in the injury pathway.
CONCLUSION: Further research is necessary to determine the success of preventive efforts in higher risk children who may react to their environment in a substantially different manner compared with less hyperactive children.