Readmission expenditures after surgery Variation in readmission expenditures after high-risk surgery: A population based study using all-payer data*

Objectives: The Hospital Readmissions Reduction Program reduces payments to hospitals with excess readmissions for three common medical conditions and recently extended its readmission program to surgical patients. We sought to investigate readmission intensity as measured by readmission cost for high-risk surgeries and examine predictors of higher readmission costs. Methods: We used data from the Healthcare Cost and Utilization Project’s State Inpatient Database to perform a retrospective cohort study of patients undergoing major chest (aortic valve replacement, coronary artery bypass grafting, lung resection) and major abdominal (abdominal aortic aneurysm repair [open approach], cystectomy, esophagectomy, pancreatectomy) surgery in 2009 and 2010. We fit a multivariable logistic regression model with generalized estimation equations to examine patient and index admission factors associated with readmission costs. Results: The 30-day readmission rate was 16% for major chest and 22% for major abdominal surgery (p<0.001). Discharge to a skilled nursing facility was associated with higher readmission costs for both chest (OR 1.99; 95% CI 1.60-2.48) and abdominal surgeries (OR 1.86; 95% CI 1.24-2.78). Comorbidities, length of stay, and receipt of blood or imaging was associated with higher readmission costs for chest surgery pati nts. Readmission >3 weeks after discharge was associated with lower costs among abdominal surgery patients. Conclusions: Readmissions after high-risk surgery are common, affecting about one in six patients. Predictors of higher readmission costs differ among major chest and abdominal surgeries. Better identifying patients susceptible to higher readmission costs may inform future interventions to either reduce the intensity of these readmissions or eliminate them altogether. Page 2 of 21 Surgical Innovation