Explaining the Paradoxical Age-based Racial Disparities in Survival After Trauma

Abstract

The objective of our study was to determine if differences in outcomes at treating facilities can help explain these age-based racial disparities in survival after trauma. It has been previously demonstrated that racial disparities in survival after trauma are dependent on age. For patients younger than 65 years, blacks had an increased odds of mortality compared with whites, but among patients 65 years or older the opposite association was found. Data on white and black trauma patients were extracted from the Nationwide Inpatient Sample (2003-2009) using International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. Standardized observed-to-expected mortality ratios were calculated for individual treating facilities, adjusting for age, sex, insurance status, mechanism of injury, overall injury severity, head injury severity, and comorbid conditions. Observed-to-expected ratios were used to benchmark facilities as high-, average-, or low-performing facilities. Proportions and survival outcomes of younger (range, 16-64 years) and older (≥65 years) patients admitted within each performance stratum were compared. A total of 934,476 patients from 1137 facilities (8.3% high-performing, 85% average-performing, and 6.7% low-performing) were analyzed. Younger black patients had a higher adjusted odds of mortality compared with younger white patients [odds ratio, 1.19; 95% confidence interval, 1.11-1.27], whereas older black patients had a lower odds of mortality compared with older white patients [odds ratio, 0.81; 95% confidence interval, 0.74-88]. A significantly greater proportion of younger black patients were treated at low-performing facilities compared with both younger white patients and older black patients (49.6% vs 42.2% and 38.7%, respectively; P < 0.05). Nearly half of all young black trauma patients are treated at low-performing facilities. However, facility-based differences do not seem to explain the paradoxical age-based racial disparities after trauma observed in the older population.