Positive and negative volume-outcome relationships in the geriatric trauma population.

IMPORTANCE In trauma populations, improvements in outcome are documented in institutions with higher case volumes. However, it is not known whether improved outcomes are attributable to the case volume within specific higher-risk groups, such as the elderly, or to the case volume among all trauma patients treated by an institution. OBJECTIVE To test the hypothesis that outcomes of trauma care for geriatric patients are affected differently by the volume of geriatric cases and nongeriatric cases of an institution. DESIGN, SETTING, AND PARTICIPANTS This retrospective cohort study using a statewide trauma registry was set in state-designated levels 1 and 2 trauma centers in Pennsylvania. It included 39 431 eligible geriatric trauma patients (aged >65 years) in the Pennsylvania Trauma Outcomes Study. MAIN OUTCOMES AND MEASURES In-hospital mortality, major complications, and mortality after major complications (failure to rescue). RESULTS Between 2001 and 2010, 39 431 geriatric trauma patients and 105 046 nongeriatric patients were captured in a review of outcomes in 20 state-designated levels 1 and 2 trauma centers. Larger volumes of geriatric trauma patients were significantly associated with lower odds of in-hospital mortality, major complications, and failure to rescue. In contrast, larger nongeriatric trauma volumes were significantly associated with higher odds of major complications in geriatric patients. CONCLUSIONS AND RELEVANCE Higher rates of in-hospital mortality, major complications, and failure to rescue were associated with lower volumes of geriatric trauma care and paradoxically with higher volumes of trauma care for younger patients. These findings offer the possibility that outcomes might be improved with differentiated pathways of care for geriatric trauma patients.