Demographics of abusive head trauma in the Commonwealth of Pennsylvania

Abstract
The aim of this study was to characterize the prevalence and demographic features of abusive head trauma (AHT) among infants and children < 36 months of age in Pennsylvania. The authors included all cases of substantiated AHT involving children < 36 months of age in Pennsylvania between 1996 and 2002 that had been reported to a statewide registry. Demographic information was derived from child abuse reports and birth certificates; the study cohort was contrasted with all infants born in Pennsylvania during the same period. The study identified 327 cases. The incidence was 14.7 cases (95% confidence interval 13.1-16.5) per 100,000 person-years for the first 2 years of life with a higher incidence during the 1st year (26.0 cases per 100,000 person-years) than the 2nd year (3.4 cases per 100,000 person-years). The incidence was similar among metropolitan, non-metropolitan, and rural counties. Significantly more cases occurred during the holiday months (October-December). The median age of victims was 4.1 months. Both victims and perpetrators were more commonly male (58.4% of victims, and 70% of identified perpetrators). Compared with the entire population of Pennsylvania parents, the parents of the study cohort were more likely to be younger, less educated, and unmarried. Both mothers and fathers were more often African-American and fathers more often Hispanic. Finally, mothers more often smoked during pregnancy, sought prenatal care later in the pregnancy, and delivered low birth weight infants. This population-based study of abusive head injuries throughout an entire state adds significantly to the growing knowledge about this condition. The results suggests that families of infants with abusive head injuries have significantly different demographic features compared with the general population, although which of these variables is independently significant cannot be ascertained from this study and require further investigation.