This study evaluated the comparative outcomes of elderly trauma patients admitted to a tertiary Surgical Intensive Care Unit (SICU) over a 5-year period (4/1/87-3/31/92). A total of 289 trauma patients 65 or older (mean age 76.3 +/- 0.4 years) were compared with 1,877 trauma patients under age 65 (mean age 31.4 +/- 0.3). The Simplified Acute Physiology Score (SAPS) severity of illness on admission for elderly trauma patients was 12.2 +/- 0.3, significantly higher than the SAPS of the younger patient group, 7.9 +/- 0.1 (P < 0.0005). Elderly survivors had higher than the SAPS of admission than their younger cohorts, 11.0 +/- 0.3 versus 7.3 +/- 0.1 (P < 0.0005), but there was no significant difference in SAPS for non-survivors. The Injury Severity Score (ISS) of elderly patients, 14.2 +/- 1.0, was not significantly higher than the ISS of younger patients, 12.3 +/- 0.3 (P = 0.06). Thirty-three elderly trauma patients (11.4%) died in the SICU, compared with 90 (4.8%) deaths in younger patients (P < 0.00005). However, when patients were stratified by admission SAPS, SICU mortality was nearly equivalent between the older and younger patient groups. An additional 14 elderly patients (4.8%) died in the hospital after SICU discharge, compared with 9 additional deaths (0.5%) in the younger patient group (P < 0.00005).(ABSTRACT TRUNCATED AT 250 WORDS)