Understanding social and environmental risks of firearm injury using geospatial patterns.

Background: For firearm-related injuries (FRI), understanding spatial injury patterns may inform intervention strategies. This study evaluates geographic FRI patterns, emphasizing (1) proximity of home address to injury location and (2) locational social determinants of health (SDOH).

Methods: We performed a retrospective analysis of FRI patients at a Level 1 trauma center between 01/2016-10/2022. Patient home and injury ZCTAs (ZCTA tabulation areas) were collected. SDOH indicators were calculated by ZIP codes using the Distressed Communities Index (DCI, ranges from 0-100 [most distressed]) and Social Deprivation Index (SDI, ranges from 1-100 [highest deprivation]). SDOH index variations and distances between ZCTAs were calculated.

Results: Of 37,537 trauma activations, 6326 were due to FRI. ZCTAs were available in 3864 (63.12 %) patients. The cohort was 86.5 % male and 85.2 % Black. Median (IQR) age was 30 (23-39) years. Home and injury locations were the same in 37.8 % of patients, within 5 miles of each other in 57.1 %, and within 20 miles in 87.2 %. DCI and SDI were significantly higher in injury vs home addresses (average DCI: home 59.5, injury 65.7; average SDI: home 71.8, injury 79.6; p < 0.001). Twenty ZCTAs (among 182) made up 68.4 % of injury locations. On linear regression, SDI and DCI were significantly associated with FRI number within ZCTAs.

Conclusions: FRI often happens close to home, and when ZCTAs differ, injury location SDOH tend to be worse. "Hotspots" with higher-than-average distress/deprivation present opportunity to maximize the impact of violence reduction; efforts should target these regions to mitigate factors perpetuating violence.