PurposeElderly trauma patients have a higher risk of severe disability and death, and this outcome burden in elderly trauma patients must be addressed in countries in which the population is aging. The clarification of the unique clinical features of elderly people who have experienced trauma is important. The purpose of this study is to evaluate the significance of the treatment for elderly severe trauma patients based on the prognosis and total hospital cost.MethodsTrauma patients transferred to our emergency department (ED) and admitted to our intensive care unit (ICU) directly or through emergency surgery between January 2013 and December 2019 were examined. We divided patients into three groups: <65 years old (Group Y); 65-79 years old (Group M); and ≥80 years old (Group E). We compared the pre- and post-trauma American Society of Anesthesiology Physical Status (ASA-PS) score and the Katz Activities of Daily Living (ADL) questionnaire at arrival among the three groups. In addition, the duration of ICU and hospital stays, hospital mortality, and total treatment costs were compared.ResultsThere were 1,652 patients admitted to ICU through the ED from January 2013 to December 2019. Of those patients, 197 trauma patients were analyzed. There was no significant difference in injury severity scores between the groups. Significant differences in both the ASA-PS and Katz-ADL scores in posttrauma status were observed among the three groups (posttrauma ASA-PS, 2.0 (2.0, 2.8) in Group Y, 3.0 (2.0, 3.0) in Group M, 3.0 (3.0, 3.0) in Group E, p < 0.001*, posttrauma Katz-ADL, 10.0 (3.3, 12.0) in Group Y, 5.5 (2.0, 10.0) in Group M, 2.0 (0.5, 4.0) in Group E, p < 0.001). The duration of both ICU and hospital stay was significantly longer in Group E compared to the other groups (ICU stay, 4.0 (3.0, 6.5) days in Group Y, 4.0 (3.0, 9.8) days in Group M, 6.5 (3.0, 15.3) days, p = 0.006, hospital stay, 16.9 (8.6, 33.0) days in Group Y, 26.7 (12.0, 51.8) days in Group M, 32.5 (12.8, 51.5) days in Group E, p = 0.005). ICU and hospital mortality were highest in Group E compared with the other groups, but the differences were not significant. Finally, the total hospital cost in Group E was significantly higher than the other groups.ConclusionsIn elderly trauma patients who required intensive care, PS and ADL in posttrauma status were worse, ICU and hospital stays were longer, and ICU and hospital mortality were higher compared with younger patients. In addition, medical costs were greater in elderly patients. It is supposed that the therapeutic effect observed in young trauma patients cannot be expected in elderly trauma patients.