Lean psoas area does not correlate with clinical outcomes in moderately to severely injured older people.

Objective: Frailty has been associated with worse outcomes in older trauma patients. Specifically, the utility of lean cross-sectional psoas muscle area (LPA) was examined as a potentially simple objective measure of frailty.

Methods: Five hundred and fifty-four patients over the age of 65 were admitted with trauma between 2011 and 2014. Two hundred and twenty-five of these had adequate computed tomography imaging available for analysis. Cross-sectional area of the psoas muscle at the inferior endplate of L4 was quantified.

Results: Multivariate regression analysis showed no significant correlation between LPA and outcomes of mortality (P = 0.82) or inpatient complications (P = 0.22). Injury Severity Score (ISS) had a strong association with both mortality (odds ratio (OR) 9.5; 95% confidence interval (CI) 2.9-30.9) and inpatient complications (OR 9.9; 95% CI 3.5-27.7). Age also had an association with mortality (OR 1.09; 95% CI 1.03-1.16) and inpatient complications (OR 1.06; 95% CI 1.01-1.12).

Conclusion: Lean psoas area was not an independent predictor of mortality or complications in a cohort of injured older patients.