Background: As the population ages, the elderly will constitute a prominent proportion of trauma patients. The elderly suffer more severe consequences from traumatic injuries compared with the young, presumably resulting in increased resource use. In this study, we sought to examine ICU resource use in trauma on the basis of age and injury severity.
Methods: This study was a retrospective review of trauma registry data prospectively collected on 26,237 blunt trauma patients admitted to all trauma centers (n = 26) in one state over 24 months (January 1996-December 1997). Age-dependent and injury severity-dependent differences in mortality, ICU length of stay (LOS), and hospital LOS were evaluated by logistic regression analysis.
Results: Elderly (age > or = 65 years, n = 7,117) patients had significantly higher mortality rates than younger (age < 65 years) trauma patients after stratification by Injury Severity Score (ISS), Revised Trauma Score, and other preexisting comorbidities. Age > 65 years was associated with a two- to threefold increased mortality risk in mild (ISS < 15, 3.2% vs. 0.4%; < 0.001), moderate (ISS 15-29, 19.7% vs. 5.4%; < 0.001), and severe traumatic injury (ISS > or = 30, 47.8% vs. 21.7%; < 0.001) compared with patients aged < 65 years. Logistic regression analysis confirmed that elderly patients had a nearly twofold increased mortality risk (odds ratio, 1.87; confidence interval, 1.60-2.18; < 0.001). Elderly patients also had significantly longer hospital LOS after stratifying for severity of injury by ISS (1.9 fewer days in the age 18-45 group, 0.89 fewer days in the age 46-64 group compared with the age > or = 65 group). Mortality rates were higher for men than for women only in the ISS < 15 (4.4% vs. 2.6%, < 0.001) and ISS 15 to 29 (21.7% vs. 17.6%, = 0.031) groups. ICU LOS was significantly decreased in elderly patients with ISS > or = 30.
Conclusion: Age is confirmed as an independent predictor of outcome (mortality) in trauma after stratification for injury severity in this largest study of elderly trauma patients to date. Elderly patients with severe injury (ISS > 30) have decreased ICU resource use secondary to associated increased mortality rates.