Background : The purpose of this study was to examine the contribution of age and gender to outcome after treatment of blunt splenic injury in adults. Methods : Through the Multi-Institutional Trials Committee of the Eastern Association for the Surgery of Trauma (EAST), 1488 adult patients from 27 trauma centers who suffered blunt splenic injury in 1997 were examined retrospectively. Results : Fifteen percent of patients were 55 years of age or older. A similar proportion of patients >= 55 went directly to the operating room compared with patients < 55 (41% vs. 38%) but the mortality for patients >= 55 was significantly greater than patients < 55 (43% vs. 23%). Patients >= 55 failed nonoperative management (NOM) more frequently than patients < 55 (19% vs. 10%) and had increased mortality for both successful NOM (8% vs. 4%, p < 0.05) and failed NOM (29% vs. 12%, p = 0.054). There were no differences in immediate operative treatment, successful NOM, and failed NOM between men and women. However, women >= 55 failed NOM more frequently than women < 55 (20% vs. 7%) and this was associated with increased mortality (36% vs. 5%) (both p < 0.05). Conclusion : Patients >= 55 had a greater mortality for all forms of treatment of their blunt splenic injury and failed NOM more frequently than patients < 55. Women >= 55 had significantly greater mortality and failure of NOM than women < 55.