The Modified Frailty Index-11 is a Poor Predictor of 1-Year Mortality and Morbidity After Ruptured Abdominal Aortic...

Previous research has shown that frailty, using the modified frailty index (mFI-11), does not correlate with 30-day outcomes after repair of a ruptured abdominal aortic aneurysm (rAAA). However, there are no studies to date investigating whether mFI-11 is associated with longer-term mortality and morbidity after rAAA repair. The aim of this study was to evaluate whether mFI-11 can be used as a risk assessment tool for predicting 1-year mortality and morbidity in patients undergoing both open and endovascular rAAA repair.

We conducted a retrospective analysis of all patients undergoing rAAA repair at a single tertiary-care center from January 2011 to November 2022. Frailty was assessed for each patient using the mFI-11, a validated frailty metric based on the Canadian Study of Health and Aging, and was defined as an mFI-11 ≥ 0.27. The primary outcome was 1-year mortality. Logistic regression, cox regression, and receiver operating characteristic (ROC) curves were used to assess mFI-11 with 1-year morbidity and mortality. Kaplan-Meier analysis was used to compare rates of survival. Categorical and continuous data were compared using χ² and Student's t-tests, respectively. For all tests, a P value of <0.05 was considered statistically significant.

Seventy-eight patients were identified during the study period (35 frail vs. 43 nonfrail) with a median follow-up of 7 months (6 months frail versus 10 months nonfrail) and a 1-year mortality rate of 40% overall (49% frail versus 33% nonfrail, P = 0.10). Multivariable analysis showed no correlation between frailty and reintervention (odds ratio 1.6 [95% confidence interval 0.1-27.6], P = 0.75), dialysis dependence (0.8 [0.1-9.2], P = 0.83), home oxygen use (1.6 [0.2-13.0], P = 0.6), and dependent mobility (0.8 [0.12-4.7], P = 0.79). The area under the ROC curve for mFI-11 was 0.58 for 1-year mortality (P = 0.2). Kaplan-Meier analysis showed no difference in rates of survival between frail and nonfrail patients (P = 0.29).

mFI-11 was not predictive of 1-year outcomes after open or endovascular rAAA repair. Other metrics are needed to more accurately assess long term risk to enable better patient and family counseling after repair of rAAA.