Comparison of Age and Modified Frailty Index-5 as Predictors of In-Hospital Mortality in Complete Traumatic Cervical Spinal Cord Injury

Abstract Frailty, as measured by the modified frailty index-5 (mFI-5), and older age are associated with increased mortality in the setting of spinal cord injury (SCI). However, a comparison of the predictive power of each measure has not been completed. We conducted a retrospective cohort study to evaluate in-hospital mortality among adult complete cervical SCI patients at participating centers of the Trauma Quality Improvement Program from 2010 to 2018. Logistic regression was used to predict in-hospital mortality, and the area under the Receiver Operating Characteristic curve (AUROC) of regression models with age, mFI-5, or age with mFI-5 was used to compare predictive power. 4,733 patients were eligible. We found significant effect of age > 75 years (OR 9.77 95% CI [7.21 13.29]) and mFI-5 ≥ 2 (OR 3.09 95% CI [1.85 4.99]) on in-hospital mortality. The AUROC of a model including age and mFI-5 (0.81 95%CI [0.79 0.84] AUROC) was comparable to a model with age alone (0.81 95%CI [0.79 0.83] AUROC). Both models were superior to a model with mFI-5 alone (0.75 95% CI [0.72 0.77] AUROC)). Our findings suggest that age provides more predictive power than mFI-5 in the prediction of in-hospital mortality for complete cervical SCI.