Past blood alcohol concentration and injury in trauma center: propensity scoring.

BACKGROUND: Evidence linking alcohol use to injury outcomes remains inconclusive, with prehospital and police department-based studies showing negative effects and hospital-based studies showing no effect or better outcomes.

OBJECTIVE: The purpose of this study was to examine the relationship of blood alcohol concentration (BAC) with injury characteristics and outcomes among trauma patients admitted to a major teaching hospital. In an effort to mitigate selection and confounding bias, propensity scoring methodology was applied, by which trauma patients were randomly assigned to high- and low-BAC groups.

METHODS: Electronic medical records were retrospectively reviewed for a period of 8 months. Of 1057 patients whose BAC was determined, 667 had BAC ≤ 0.08 g/dL and 390 had BAC > 0.08 g/dL. Injury characteristics were defined as injury type, injury location, and trauma level. Injury outcomes were defined as hospitalization, length of hospital stay, and in-hospital death. Adjusted odds ratios (aOR) and their 95% confidence intervals (CI) were calculated using multivariate logistic regression models and propensity scoring was applied.

RESULTS: A positive relationship was observed between BAC and unintentional injury (aOR = 1.08; 95% CI 1.01-1.17). Although injuries of the extremities were less likely to occur in patients with high BAC (aOR = 0.88; 95% CI 0.80-0.98), head injury was positively associated with high BAC (aOR = 1.27; 95% CI 1.14-1.42). Also, Level I trauma patients had nearly 60% greater odds of having a high BAC than Level II trauma patients.

CONCLUSIONS: A high alcohol level in the blood appears to be predictive of more unintentional injury, head injury, and Level I trauma activation and less injuries in extremities.