The relation between physical fitness, frailty and all-cause mortality after elective endovascular abdominal aortic aneurysm repair

Abstract

Background: Accurate determination of probable surgical outcomes is fundamental in decision-making regarding appropriate abdominal aortic aneurysm treatment. These outcomes depend, among other factors, on patient-related factors such as physical fitness. The primary aim of this study was to evaluate the correlation between physical fitness, measured by the metabolic equivalent of task (MET) score and the five-factor Modified Frailty Index (MFI-5), and all-cause mortality.

Methods: Four hundred twenty-nine patients undergoing elective endovascular treatment of an infrarenal aortic aneurysm (EVAR) from January 2011 to September 2018 were identified in an existing local abdominal aortic aneurysm database. Physical fitness was measured by the MFI-5 and the METs as registered during preoperative screening. The primary end point was 1-year all-cause mortality and secondary end points included 5-year all-cause mortality, freedom from aneurysm-related mortality and aneurysm-related reinterventions. Correlations were analyzed using Spearman's rho and survival was analyzed using Kaplan-Meier analyses. The effect of physical fitness on mortality was assessed by binary logistics regression analyses.

Results: There was a positive correlation between the MFI-5 and 1-year all-cause mortality (Rho = 0.163; P = .001), but not between the METs and 1-year all-cause mortality (Rho = -0.083; P = .124). A significant correlation between both MFI-5 and METs and 5-year all-cause mortality was observed (Rho = 0.255; P < .001 and Rho = -0.154; P = .004). When stratified by the MFI-5, the 1- and 5-year follow-up survival rates were 95.1% and 85.9%, respectively, in the group with the lowest MFI-5 and 74.5% and 33.1% in the group with the highest MFI-5 score (P = .007 and P < .001). When stratified by METs categories for 1-year follow-up, no significant differences in survival between the groups were observed (P = .090). The 5-year follow-up survival rate was 39.4% in the lowest METs category and 76.3% in the highest METs category (P = .039). Logistic regression analysis, assessing the impact of age, sex, METs, and the MFI-5 on the risk of all-cause mortality, showed that only age and the MFI-5 made a significant contribution.

Conclusions: There is a significant positive association between the MFI-5 and both the 1- and 5-year all-cause mortality rates after EVAR; METs only correlated with the 5-year all-cause mortality. Only age and the MFI-5 contributed to predicting overall survival after EVAR; therefore, it could be recommended to add the MFI-5 for guidance in preoperative counselling.

Keywords: Aortic aneurysm; Elective surgical procedures; Frailty; Physical fitness.