Our objective was to examine patterns of withholding/withdrawal (WH/WD) of life support in trauma patients and to determine whether WD/WH of life support is used more frequently in elderly patients. This is a retrospective cohort study of injured elderly (> or = 65 years) and young patients (< 65 years) from 1994 through 1998 treated at a surgical intensive care unit in a community tertiary-care hospital. We studied the cases of 82 patients (30 elderly and 52 young patients) with WH/WD of life support after injury. Our main outcome measures were demographic and clinical characteristics of elderly and young patients undergoing WH/WD of life support after injury with an association between age and WH/WD of life support. Of 102 total trauma patient deaths 82 had WH/WD of life support. This mode was chosen in 52 (80%) patients under the age of 65 and in 30 (81%) patients age 65 or greater. Patients in the younger cohort had a higher mean Injury Severity Score and Abbreviated Injury Score of 5 (P < 0.05). The elderly cohort had a higher incidence of pre-existing disease (< 0.001). Length of stay was similar between the populations. We conclude that the elderly were no more likely to have WH/WD of life support than were younger patients. However, the older patients were less severely injured as measured by Injury Severity Score and percentage with Abbreviated Injury Score head of 5. Other factors such as the presence of pre-existing disease may influence the decision to withhold or withdraw life support to a greater degree than the actual severity of injuries.