Skeletal Muscle Quality Evaluation for Prognostic Stratification in the Emergency Department of Patients ≥ 65 Years with Major Trauma

Background: In patients over 65 years who experience severe trauma the underlying health status has a significant impact on overall mortality. This study aims to assess if CT evaluation of skeletal muscle quality could be a risk stratification tool in the ED for these patients. Methods: Retrospective observational study between January 2018 and September 2021, including consecutive patients ≥ 65 years admitted to the ED for a major trauma (defined as Injury Severity Score > 15). Muscle quality analysis was made by specific software (Slice-O-Matic v5.0, Tomovision®, Montreal, QC, Canada) on a CT-Scan slice at the level of the third lumbar vertebra. Results: 263 patients were included (72.2% males, median age 76 [71-82]), and 88 (33.5%) deceased. The deceased patients had a significantly lower skeletal muscle area density (SMAd) compared to survivors. The multivariate Cox regression analysis confirmed that SMAd < 38 at the ED admission was an independent risk for death (adjusted HR 1.68 [1.1 – 2.7]). The analysis also revealed that, among the survivors after the first week of hospitalization, the patients with low SMAd had an increased risk of death (adjusted HR 3.12 [1.2 – 7.9]). Conclusions: The skeletal muscle density evaluated by a CT scan at ED admission could be a valuable risk stratification tool for patients ≥ 65 years with major trauma. In patients with SMAd