Predicting survival in geriatric trauma patients: A comparison between the TRISS methodology and the Geriatric Trauma Outcome Score.

INTRODUCTION: We compared the Geriatric Trauma Outcome Score (GTOS) with the probability of survival using the TRISS methodology (PS-TRISS) in geriatric severe trauma patients admitted to Intensive Care Units (ICU) participating in the Spanish trauma ICU registry (RETRAUCI).

METHODS: Retrospective analysis from the RETRAUCI. Quantitative data were reported as median (Interquartile Range (IQR)), and categorical data as number (percentage). We analyzed the validity of the GTOS and PS-TRISS to predict survival. Discrimination was analyzed using receiver operating characteristics curves. Calibration was analyzed using the Hosmer-Lemeshow goodness-of-fit test. A P value <.05 was considered statistically significant.

RESULTS: The cohort included 1417 patients aged ≥ 65 years. Median age was 75.5 (70.5-80.5), 1003 patients were male (68.2%) and median Injury Severity Score was 18 (13-25). Mechanical ventilation was required in 61%. Falls were the mechanism of injury in 659 patients (44.8%). In-hospital mortality rate was 18.2%. The areas under the curve were: PS-TRISS 0.69 (95%CI 0.66-0.73), and GTOS 0.66 (95%CI 0.62-0.70); P<.05. Both scores overestimated mortality in the upper range of predicted mortality.

CONCLUSIONS: In our sample of geriatric severe trauma patients, the accuracy of GTOS was lower than the accuracy of the PS-TRISS to predict in-hospital survival. The calibration of both scores for the geriatric population was deficient.