Risk factors for assaultive reinjury and death following a nonfatal firearm assault injury: A population-based retrospective cohort study

Abstract

Individuals with a firearm injury are at high risk of subsequent firearm victimization, but characteristics associated with sustaining recurrent firearm injuries are not well understood. In this retrospective cohort study, we sought to quantify the hazards of sustaining subsequent assaultive firearm injuries among people with an initial firearm assault injury and to identify characteristics associated with recurrent victimization. Using hospital discharge, emergency department, and mortality records, we identified and followed all individuals aged ≥15 years with a nonfatal firearm assault injury resulting in an emergency department visit or hospital admission in California, 2005–2013. We model transitions from one injury to the next and from injury to death, accounting for event history, covariates, and competing risks using multistate models. 29,156 people had an index nonfatal firearm assault injury. Among individuals with 1 such injury, 3.1% had additional nonfatal firearm assault injuries and 1.0% subsequently died from firearm homicide. Among individuals with 2+ nonfatal firearm assaults, 2.0% died from firearm homicide. The estimated transition probability for 1 to 2+ nonfatal injuries reached 10% by 8.5 years post-index injury. The rate of subsequent nonfatal firearm assault injury was highest among men (hazard ratio [HR]: 3.87; 95% confidence interval [CI]: 2.63–5.69) and Blacks (vs. whites) (HR: 2.69; 95% CI: 1.99–3.64). Identification of additional risk markers will require more detailed individual-level data; nonetheless, this study supports the generalizability of findings from smaller studies, provides broad guidance for allocating scarce resources, and suggests that interventions on root causes of violence disparities may have downstream effects on recurrence.