Assessing Morbidity and Mortality in Adult Patients with Acute Traumatic Cervical Spinal Cord Injury Using a Modified Risk Analysis Index

Introduction: The risk analysis index (RAI) is a comprehensive assessment of frailty that has been used to predict neurosurgical outcomes. The aim of this study was to assess whether frailty, measured by a modified RAI (mRAI), was an independent predictor of adverse events (AEs), non-routine discharge, and in-hospital mortality for patients with acute cervical spinal cord injuries (SCIs).

Methods: A retrospective cohort study was performed using the American College of Surgeons Trauma Quality Programs database. All adult patients presenting with acute cervical SCI from 2016-2022 were stratified by mRAI score into 3 frailty groups: Robust (mRAI 0-10), Frail (mRAI 11-20), and Very Frail (mRAI ≥21). Patient demographics, comorbidities, type of injury, diagnostic and treatment modality, AEs, and in-patient mortality were assessed. A multivariate logistic regression analysis was used to identify independent predictors of AEs, non-routine discharge, and in-hospital mortality.

Results: 71,048 patients were identified and stratified by mRAI score: 59,796 Robust (84.2%), 9,558 Frail (13.5%), and 1,694 Very Frail (2.4%). The proportion of patients with SCI secondary to a fall significantly increased with increasing frailty level (Robust: 44.1% vs. Frail: 70.2% vs. Very Frail: 82.3%; p< 0.001). The percentage of patients experiencing any AE also increased with increasing frailty level (Robust: 21.5% vs. Frail: 24.4% vs. Very Frail: 25.0%; p< 0.001). Significantly greater proportions of Very Frail patients experienced non-routine discharges (Robust: 72.3% vs. Frail: 85.2% vs. Very Frail: 91.0%; p< 0.001) and in-hospital mortality (Robust: 10.9% vs. Frail: 18.3% vs. Very Frail: 29.2%; p< 0.001). On multivariate regression analysis, both Frail (OR: 1.42; 95% CI: 1.25-1.61; p< 0.001) and Very Frail (OR: 2.09; 95% CI: 1.46-2.99; p< 0.001) mRAI scores predicted non-routine discharge, but only Frail mRAI score (OR: 1.12; 95% CI: 1.05-1.21; p=0.001) was significantly associated with increased odds of developing AEs. Frail (OR: 1.50; 95% CI: 1.36-1.65; p< 0.001) and Very Frail (OR: 2.79; 95% CI: 2.36-3.29; p< 0.001) mRAI scores were also found to be independent predictors of in-hospital mortality.

Conclusion : Our study suggests that modified RAI may be utilized to assess morbidity and mortality in patients presenting with spinal cord injury.