Variation in center-level frailty burden and the impact of frailty on long-term survival in patients undergoing elective repair for abdominal aortic aneurysms

Abstract

ObjectiveFrailty is increasingly recognized as a key determinant in predicting postoperative outcomes. Centers that see more frail patients may not be captured in risk adjustment, potentially accounting for poorer outcomes in hospital comparisons. We aimed to (1) determine the effect of frailty on long-term mortality in patients undergoing elective abdominal aortic aneurysm (AAA) repair and (2) evaluate the variability in frailty burden among centers in the Vascular Quality Initiative (VQI) database. MethodsPatients undergoing elective open and endovascular AAA repair (2003-2017) were identified, and those with complete data on component variables of the VQI-derived Risk Analysis Index (VQI-RAI) and centers with ≥10 AAA repairs were included. VQI-RAI characteristics are sex, age, body mass index, renal failure, congestive heart failure, dyspnea, preoperative ambulation, and functional status. Frailty was defined as VQI-RAI ≥35 based on prior work in surgical patients using other quality improvement databases. This corresponds to the top 12% of patients at risk in the VQI. Center-level VQI-RAI differences were assessed by analysis of variance test. Relationships between frailty and survival were compared by Kaplan-Meier analysis and the log-rank test for open and endovascular procedures. Multivariable hierarchical Cox proportional hazards regression models were calculated with random intercepts for center, controlling for frailty, race, insurance, AAA diameter, procedure type, AAA case mix, and year. ResultsA total of 15,803 patients from 185 centers were included. Mean VQI-RAI scores were 27.6 (standard deviation, 5.9; range, 4-56) and varied significantly across centers (F = 2.41, P < .001). The percentage of frail patients per center ranged from 0% to 40.0%. In multivariable analysis, frailty was independently associated with long-term mortality (hazard ratio, 2.88; 95% confidence interval, 2.6-3.2) after accounting for covariates and center-level variance. Open AAA repair was not associated with long-term mortality after adjusting for frailty (hazard ratio, 0.98; 95% confidence interval, 0.86-1.13). There was a statistically significant difference in the percentage of frail patients compared with nonfrail patients who were discharged to a rehabilitation facility or nursing home after both open (40.5% vs 17.8%; P < .0001) and endovascular repair (17.7% vs 4.6%; P < .0001). ConclusionsThere is considerable variability of preoperative frailty among VQI centers performing elective AAA repair. Adjusting for center-level variation, frailty but not procedure type had a significant association with long-term mortality; however, frailty and procedure type were both associated with nonhome discharge. Routine measurement of frailty preoperatively by centers to identify high-risk patients may help mitigate procedural and long-term outcomes and improve shared decision-making regarding AAA repair.