Association between intentional injury and long-term survival after trauma

To determine the risk-adjusted mortality of intentionally injured patients within 7 to 9 years postinjury, compared with unintentionally injured patients.

Violent injury contributes significantly to trauma mortality in the United States. Homicide is the second leading killer of American youth, aged 15 to 24 years. Long-term survival among intentionally injured patients has not been well studied. It is also unknown whether intentionally injured patients have worse long-term survival compared with unintentionally or accidentally injured patients with equivalent injuries.

Adult trauma patients admitted for 24 hours or more and discharged alive from the Johns Hopkins Hospital from January 1, 1998, to December 31, 2000, were included. The primary outcome was mortality within 7 to 9 years postinjury. Long-term patient survival was determined using the National Death Index. The association between injury intentionality and mortality was investigated using a Cox proportional hazard regression model, adjusted for confounders such as injury severity and patient race, socioeconomic status, and comorbid conditions. Overall differences in survival between those with intentional versus unintentional injury were also determined by comparing adjusted Kaplan-Meier survival curves.

A total of 2062 patients met inclusion criteria. Of these, 56.4% were intentionally injured and 43.6% were unintentionally injured. Compared with unintentionally injured patients, intentionally injured patients were younger and more often male and from a zip code with low median household income. Approximately 15% of all patients had died within 7 to 9 years of follow-up. Older age and presence of comorbidities were associated with this outcome; however, intentional injury was not found to be significantly associated with long-term mortality rates. There was also no significant difference in survival curves between groups; intentionally injured patients were much more likely to die of a subsequent injury, whereas those with unintentional injury commonly died of noninjury causes.

There was no significant difference in mortality between intentionally injured and unintentionally injured patients within 7 to 9 years postinjury. These results confirm the long-term effectiveness of lifesaving trauma care for those with intentional injury. However, given that patients with intentional injuries were more likely to suffer a subsequent violent death, interventions focused on breaking the cycle of violence are needed.