Using geographic information systems to identify locations of drug overdoses in Los Angeles

Background/Purpose: Opioid overdose is a significant cause of premature mortality in Los Angeles (LA) County. Training programs aimed at teaching drug users to effectively respond to opioid overdose were implemented by two community-based organizations (CBO) in LA: Homeless Healthcare LA and Common Ground Westside. To date, GIS analysis has not been used to describe location of overdose relative to location of training programs and/or census bureau data. Methods: We interviewed 101 trained and untrained clients of 2 CBO from June 2010 to April 2011. Locations of 130 overdoses experienced and/or witnessed by respondents were geocoded with ArcGIS. The location of the CBO and socio-economic data (i.e. crime rate, average income) from the US Census will be overlaid with the overdose map to assess the spatial variations. This will allow us to identify areas of LA with an increased drug overdose burden. Results: These maps will combine epidemiological, census and geographic data in a graphical form. We expect to find high spatial correlation between overdose location, crime rate and low income areas. The overlay of data will address fundamental question of program effectiveness including service utilization by the targeted population. Conclusions: This project will demonstrate the utility of GIS mapping for intervention/prevention planning. Results can inform overdose prevention programs by identifying “hot spots” within the CBO catchment areas that experience elevated rates of overdose. Public health practitioners could use these findings to more effectively appropriate resources and develop strategies for targeted outreach to populations who are exposed to opioid overdose.