Trends and Determinants of Readmissions to Another Facility After Endovascular Aortic Repair

Background: Endovascular aneurysm repair (EVAR) has become the procedure of choice for abdominal aortic aneurysms (AAAs). It has been previously reported that significant percentage of patients were being readmitted to another hospital after complications after EVAR. We aimed to evaluate trends and clinical predictors of readmission to another (secondary) hospital after index EVAR. Methods: The Nationwide Readmissions Database (NRD) was queried for all 30-day readmissions after an index EVAR procedure from 2012 to 2014. Readmission diagnosis, patient demographics, and hospital characteristics were collected regarding those patients who were admitted to another care facility after EVAR. Univariate analysis and multivariable logistic regression model was used to identify predictors for readmission to a different hospital. Results: Between 2012 and 2014, 3,215 patients were readmitted to another hospital within 30 days of their index EVAR constituting 22.8% of a total 14,073 readmissions during that time period. Comorbidities of patients examined were similar between those patients readmitted to the primary hospital versus the secondary hospital except for the incidence of hypothyroidism (P < 0.001). Higher proportion of patients admitted to a different hospital had Medicare and Medicaid insurance (P < 0.047). In addition, higher proportion of patients readmitted to secondary hospitals had EVAR performed at smaller (<100 beds) hospitals (P = 0.002). Univariate analysis demonstrated that patients readmitted to another hospital were slightly older and had higher index length of stay and higher index hospital cost after EVAR (P < 0.001). In a multivariate model, index EVAR at a small hospital (odds ratio [OR]: 1.7) and the diagnosis of hypothyroidism (OR: 1.54) were independent determinants of readmission to another care facility. Conclusions: Significant proportion of patients is being readmitted elsewhere after elective EVAR adding complexity to the determination of appropriate healthcare resource allocation. In our study, index EVAR at a small hospital (<100 beds) and pre-existing medical comorbidity of hypothyroidism were significant predictors for unanticipated readmission to a different hospital.