A novel risk scoring system reliably predicts readmission after pancreatectomy

Abstract

Background: Postoperative readmissions have been proposed by Medicare as a quality metric and can impact provider reimbursement. Because readmission after pancreatectomy is common, we sought to identify factors associated with readmission to establish a predictive risk scoring system.

Study design: A retrospective analysis of 2,360 pancreatectomies performed at 9 high-volume pancreatic centers between 2005 and 2011 was performed. Forty-five factors strongly associated with readmission were identified. To derive and validate a risk scoring system, the population was randomly divided into 2 cohorts in a 4:1 fashion. A multivariable logistic regression model was constructed and scores were assigned based on the relative odds ratio (OR) of each independent predictor. A composite Readmission after Pancreatectomy (RAP) score was generated and then stratified to create risk groups.

Results: Overall, 464 (19.7%) patients were readmitted within 90 days. Eight pre- and postoperative factors, including earlier MI (OR = 2.03), American Society of Anesthesiologists class ≥ 3 (OR = 1.34), dementia (OR = 6.22), hemorrhage (OR = 1.81), delayed gastric emptying (OR = 1.78), surgical site infection (OR = 3.31), sepsis (OR = 3.10), and short length of stay (OR = 1.51) were independently predictive of readmission. The 32-point RAP score generated from the derivation cohort was highly predictive of readmission in the validation cohort (area under the receiver operating curve = 0.72). The low-risk (0 to 3), intermediate-risk (4 to 7), and high-risk (>7) groups correlated with 11.7%, 17.5%, and 45.4% observed readmission rates, respectively (p < 0.001).

Conclusions: The RAP score is a novel and clinically useful risk scoring system for readmission after pancreatectomy. Identification of patients with increased risk of readmission using the RAP score will allow efficient resource allocation aimed to attenuate readmission rates. It also has potential to serve as a new metric for comparative research and quality assessment.

Figure 1

Linear regression model of observed versus predicted readmission according to the Readmission After Pancreatectomy (RAP) score.