Variation in readmission expenditures after high-risk surgery

Abstract

Background: 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.

Materials and methods: We used 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-d 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 (odds ratio [OR]: 1.99; 95% confidence interval [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 patients. Readmission >3 wk 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.

Keywords: Cost; Failure to rescue; High-risk surgery; Readmission intensity; Readmissions.

Figure 1

Estimated effect (adjusted odds ratio* and 95% CI) of each predictor on the highest versus lowest readmission costs for patients undergoing major chest surgery: Results of a multivariable logistic regression analysis For patients undergoing major chest surgery, comorbidities, increasing length of stay, discharge to a skilled nursing facility, and receipt of a blood transfusion or imaging during the index admission were associated with higher readmission costs. Residing in Iowa or North Carolina and receiving an AVR or CABG (as opposed to a lung resection) were associated with lower readmission costs. *The effect of each predictor was adjusted for all other predictors in the model. **Includes intermediate care facility, other facility, or short-term hospital. Abbreviations: AVR, aortic valve replacement; CABG, coronary artery bypass graft; MRI, magnetic resonance imaging

Figure 2

Estimated effect (adjusted odds ratio* and 95% CI) of each predictor on the highest versus lowest readmission costs for patients undergoing major abdominal surgery: Results of a multivariable logistic regression analysis For patients undergoing major abdominal surgery, discharge to a skilled nursing facility or residing in Washington were associated with higher readmission costs. Conversely, readmission greater than three weeks after discharge was associated with lower readmission costs. *The effect of each predictor was adjusted for all other predictors in the model. **Includes intermediate care facility, other facility, or short-term hospital. Abbreviations: AAA, abdominal aortic aneurysm; MRI, magnetic resonance imaging