Patient-level factors are more salient than a legislation prohibiting minors in bars in predicting unintentional injury hospitalizations

BACKGROUND: Alcohol related homicide, suicide and aggravated assault represent the largest costs for the state of Illinois. Previous research has examined the impact of some alcohol-related policies on youth alcohol use and alcohol-related harm in the United States but findings have been mixed. To our knowledge, no study has provided a detailed epidemiology of the relationship between the impacts of alcohol policies on unintentional injury in Illinois. Therefore, the purpose of this study is to determine whether a legislation that prohibit minors under 21 years old in establishments that serve alcohol is more salient than individual level factors in predicting hospitalization for traumatic unintentional injuries. METHODS: A retrospective observational study of data abstracted from 6,139 patients aged 10 to 19 hospitalized in Illinois Level I and Level II trauma centers. Patient data from 2006 to 2015 was linked with the city-level alcohol-related legislation (n = 514 cities). The response variable was whether a patient tested positive or negative for blood alcohol concentration (BAC) at the time of admission. Mixed-effects logistic regression analyses were conducted to model the patient and city level legislation effect of having a positive BAC test result on hospitalizations after adjusting for the legislation and patient factors. RESULTS: After adjustment, patients aged 15 to 19 and white patients who tested positive for BAC at the time of admission had the greater odds of hospitalization for traumatic alcohol-related unintentional injuries compared to patients who had a negative BAC test result. However, odds of hospitalization decreased for female patients and for those with private insurance, and over time, but a significant decrease in such hospitalizations occurred during 2010, 2014 and 2015. The alcohol-related legislation of interest was not a significant predictor of traumatic alcohol-related unintentional injury hospitalization. CONCLUSIONS: Patient-level covariates were significant predictors of traumatic alcohol-related unintentional injury hospitalization; an alcohol-related legislation may not reduce hospitalizations for young patients aged 10 to 19. Therefore, to prevent underage drinking and consequences, interventions should target sex/gender, race/ethnicity and focus on both individual and environmental strategies. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12889-019-7327-7) contains supplementary material, which is available to authorized users.