Neighbourhood alcohol environment and injury risk: a spatial analysis of pedestrian injury in Baltimore City.

Objectives: The purpose of this study was to investigate the contribution of neighbourhood disorder around alcohol outlets to pedestrian injury risk.

Methods: A spatial analysis was conducted on census block groups in Baltimore City. Data included pedestrian injury EMS records from 1 January 2014 to 15 April 2015 (n=858), off-premise alcohol outlet locations for 2014 (n=693) and neighbourhood disorder indicators and demographics. Negative binomial regression models were used to determine the relationship between alcohol outlet count and pedestrian injuries at the block group level, controlling for other neighbourhood factors. Attributable risk was calculated by comparing the total population count per census block group to the injured pedestrian count.

Results: Each one-unit increase in the number of alcohol outlets was associated with a 14.2% (95% CI 1.099 to 1.192, P<0.001) increase in the RR of neighbourhood pedestrian injury, adjusting for traffic volume, pedestrian volume, population density, per cent of vacant lots and median household income. The attributable risk was 10.4% (95% CI 7.7 to 12.7) or 88 extra injuries. Vacant lots was the only significant neighbourhood disorder indicator in the final adjusted model (RR=1.016, 95% CI 1.007 to 1.026, P=0.003). Vacant lots have not been previously investigated as possible risk factors for pedestrian injury.

Conclusions: This study identifies modifiable risk factors for pedestrian injury previously unexplored in the literature and may provide evidence for alcohol control strategies (eg, liquor store licencing, zoning and enforcement).