LAUSR

INTRODUCTION Few studies have used both spatial and non-spatial techniques to the study of alcohol outcomes. The objectives of this study were to identify clusters of traumatic unintentional injury hospitalizations by gender and blood alcohol concentration (BAC), and to determine trends and correlates by BAC levels. METHODS State Trauma Registry data capturing unintentional injuries for those aged 10 to 24 hospitalized with negative and positive BAC levels (n = 6233) were analyzed from 2006 to 2015 for all Chicago block groups. Spatial clustering techniques were applied to detect spatial clusters and Generalized Estimating Equations to determine correlates and trends while controlling for correlation within block groups. RESULTS Regardless of BAC level, hospitalization rates decreased for all age groups between 2006 to 2010 and 2011 to 2015 from 94.41 to 67.69 per 100,000 population. The decline for males hospitalized with positive BAC was 1.4 times greater than the decline for their female counterparts. Risk factors included being male, black or of a minority race, having no private insurance and living in a disadvantaged neighborhood. Male hospitalization rates clustered among 33 census block groups located in three Chicago Community Areas. No clustering was detected for female patients. Motor vehicle accidents were the leading cause of hospitalization. CONCLUSIONS Hospitalizations are decreasing in Chicago, yet the risk is concentrated, with greater decreasing rates among males than females. Spatial approaches can be valuable tools in analyzing substance abuse outcomes, to identify high-risk areas and shifts in risk within a large geographic area.